wip

This reverts commit 4ffa7fb12b.

.env.example

@@ -5,17 +5,29 @@
 # All values have reasonable defaults, so you only need to change the ones you
 # want to override.
 
+# Use production mode unless you are developing locally.
+NODE_ENV=production
+
 # ------------------------------------------------------------------------------
 # General settings:
 
 # The title displayed on the info page.
 # SERVER_TITLE=Coom Tunnel
 
-# Model requests allowed per minute per user.
+# The route name used to proxy requests to APIs, relative to the Web site root.
-# MODEL_RATE_LIMIT=4
+# PROXY_ENDPOINT_ROUTE=/proxy
+
+# Text model requests allowed per minute per user.
+# TEXT_MODEL_RATE_LIMIT=4
+# Image model requests allowed per minute per user.
+# IMAGE_MODEL_RATE_LIMIT=2
+
+# Max number of context tokens a user can request at once.
+# Increase this if your proxy allow GPT 32k or 128k context
+# MAX_CONTEXT_TOKENS_OPENAI=16384
 
 # Max number of output tokens a user can request at once.
-# MAX_OUTPUT_TOKENS_OPENAI=300
+# MAX_OUTPUT_TOKENS_OPENAI=400
 # MAX_OUTPUT_TOKENS_ANTHROPIC=400
 
 # Whether to show the estimated cost of consumed tokens on the info page.
@@ -27,7 +39,12 @@
 # CHECK_KEYS=true
 
 # Which model types users are allowed to access.
-# ALLOWED_MODEL_FAMILIES=claude,turbo,gpt4,gpt4-32k
+# The following model families are recognized:
+# turbo | gpt4 | gpt4-32k | gpt4-turbo | dall-e | claude | claude-opus | gemini-pro | mistral-tiny | mistral-small | mistral-medium | mistral-large | aws-claude | azure-turbo | azure-gpt4 | azure-gpt4-32k | azure-gpt4-turbo | azure-dall-e
+# By default, all models are allowed except for 'dall-e' / 'azure-dall-e'.
+# To allow DALL-E image generation, uncomment the line below and add 'dall-e' or
+# 'azure-dall-e' to the list of allowed model families.
+# ALLOWED_MODEL_FAMILIES=turbo,gpt4,gpt4-32k,gpt4-turbo,claude,claude-opus,gemini-pro,mistral-tiny,mistral-small,mistral-medium,mistral-large,aws-claude,azure-turbo,azure-gpt4,azure-gpt4-32k,azure-gpt4-turbo
 
 # URLs from which requests will be blocked.
 # BLOCKED_ORIGINS=reddit.com,9gag.com
@@ -36,8 +53,10 @@
 # Destination to redirect blocked requests to.
 # BLOCK_REDIRECT="https://roblox.com/"
 
-# Whether to reject requests containing disallowed content.
+# Comma-separated list of phrases that will be rejected. Only whole words are matched.
-# REJECT_DISALLOWED=false
+# Surround phrases with quotes if they contain commas.
+# Avoid short or common phrases as this tests the entire prompt.
+# REJECT_PHRASES="phrase one,phrase two,"phrase three, which has a comma",phrase four"
 # Message to show when requests are rejected.
 # REJECT_MESSAGE="This content violates /aicg/'s acceptable use policy."
 
@@ -45,8 +64,12 @@
 # Requires additional setup. See `docs/google-sheets.md` for more information.
 # PROMPT_LOGGING=false
 
-# The port to listen on.
+# The port and network interface to listen on.
 # PORT=7860
+# BIND_ADDRESS=0.0.0.0
+
+# Whether cookies should be set without the Secure flag, for hosts that don't support SSL.
+# USE_INSECURE_COOKIES=false
 
 # Detail level of logging. (trace | debug | info | warn | error)
 # LOG_LEVEL=info
@@ -56,36 +79,57 @@
 # See `docs/user-management.md` for more information and setup instructions.
 # See `docs/user-quotas.md` to learn how to set up quotas.
 
-# Which access control method to use. (none | proxy_token | user_token)
+# Which access control method to use. (none | proxy_key | user_token)
 # GATEKEEPER=none
 # Which persistence method to use. (memory | firebase_rtdb)
 # GATEKEEPER_STORE=memory
 
 # Maximum number of unique IPs a user can connect from. (0 for unlimited)
 # MAX_IPS_PER_USER=0
+# Whether user_tokens should be automatically disabled when reaching the IP limit.
+# MAX_IPS_AUTO_BAN=true
 
 # With user_token gatekeeper, whether to allow users to change their nickname.
 # ALLOW_NICKNAME_CHANGES=true
 
 # Default token quotas for each model family. (0 for unlimited)
+# DALL-E "tokens" are counted at a rate of 100000 tokens per US$1.00 generated,
+# which is similar to the cost of GPT-4 Turbo.
+# DALL-E 3 costs around US$0.10 per image (10000 tokens).
+# See `docs/dall-e-configuration.md` for more information.
 # TOKEN_QUOTA_TURBO=0
 # TOKEN_QUOTA_GPT4=0
 # TOKEN_QUOTA_GPT4_32K=0
+# TOKEN_QUOTA_GPT4_TURBO=0
+# TOKEN_QUOTA_DALL_E=0
 # TOKEN_QUOTA_CLAUDE=0
+# TOKEN_QUOTA_GEMINI_PRO=0
+# TOKEN_QUOTA_AWS_CLAUDE=0
 
 # How often to refresh token quotas. (hourly | daily)
 # Leave unset to never automatically refresh quotas.
 # QUOTA_REFRESH_PERIOD=daily
 
+# Specifies the number of proxies or load balancers in front of the server.
+# For Cloudflare or Hugging Face deployments, the default of 1 is correct.
+# For any other deployments, please see config.ts as the correct configuration
+# depends on your setup. Misconfiguring this value can result in problems
+# accurately tracking IP addresses and enforcing rate limits.
+# TRUSTED_PROXIES=1
+
 # ------------------------------------------------------------------------------
 # Secrets and keys:
-# Do not put any passwords or API keys directly in this file.
+# For Huggingface, set them via the Secrets section in your Space's config UI. Dp not set them in .env.
-# For Huggingface, set them via the Secrets section in your Space's config UI.
 # For Render, create a "secret file" called .env using the Environment tab.
 
 # You can add multiple API keys by separating them with a comma.
+# For AWS credentials, separate the access key ID, secret key, and region with a colon.
 OPENAI_KEY=sk-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
 ANTHROPIC_KEY=sk-ant-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+# See `docs/aws-configuration.md` for more information, there may be additional steps required to set up AWS.
+AWS_CREDENTIALS=myaccesskeyid:mysecretkey:us-east-1,anotheraccesskeyid:anothersecretkey:us-west-2
+# See `docs/azure-configuration.md` for more information, there may be additional steps required to set up Azure.
+AZURE_CREDENTIALS=azure-resource-name:deployment-id:api-key,another-azure-resource-name:another-deployment-id:another-api-key
 
 # With proxy_key gatekeeper, the password users must provide to access the API.
 # PROXY_KEY=your-secret-key

.gitignore

@@ -1,6 +1,11 @@
-.env
+.aider*
+.env*
+!.env.vault
 .venv
 .vscode
+.idea
 build
 greeting.md
 node_modules
+
+http-client.private.env.json

.prettierrc

@@ -9,5 +9,6 @@
         "bracketSameLine": true
       }
     }
-  ]
+  ],
+  "trailingComma": "es5"
 }

README.md

@@ -1,34 +1,53 @@
 # OAI Reverse Proxy
 
-Reverse proxy server for the OpenAI and Anthropic APIs. Forwards text generation requests while rejecting administrative/billing requests. Includes optional rate limiting and prompt filtering to prevent abuse.
+Reverse proxy server for various LLM APIs.
 
 ### Table of Contents
 - [What is this?](#what-is-this)
-- [Why?](#why)
+- [Features](#features)
-- [Usage Instructions](#setup-instructions)
+- [Usage Instructions](#usage-instructions)
-  - [Deploy to Huggingface (Recommended)](#deploy-to-huggingface-recommended)
+  - [Self-hosting](#self-hosting)
-  - [Deploy to Repl.it (WIP)](#deploy-to-replit-wip)
+  - [Alternatives](#alternatives)
+    - [Huggingface (outdated, not advised)](#huggingface-outdated-not-advised)
+    - [Render (outdated, not advised)](#render-outdated-not-advised)
 - [Local Development](#local-development)
 
 ## What is this?
-If you would like to provide a friend access to an API via keys you own, you can use this to keep your keys safe while still allowing them to generate text with the API. You can also use this if you'd like to build a client-side application which uses the OpenAI or Anthropic APIs, but don't want to build your own backend. You should never embed your real API keys in a client-side application. Instead, you can have your frontend connect to this reverse proxy and forward requests to the downstream service.
+This project allows you to run a reverse proxy server for various LLM APIs.
 
-This keeps your keys safe and allows you to use the rate limiting and prompt filtering features of the proxy to prevent abuse.
+## Features
-
+- [x] Support for multiple APIs
-## Why?
+  - [x] [OpenAI](https://openai.com/)
-OpenAI keys have full account permissions. They can revoke themselves, generate new keys, modify spend quotas, etc. **You absolutely should not share them, post them publicly, nor embed them in client-side applications as they can be easily stolen.**
+  - [x] [Anthropic](https://www.anthropic.com/)
-
+  - [x] [AWS Bedrock](https://aws.amazon.com/bedrock/)
-This proxy only forwards text generation requests to the downstream service and rejects requests which would otherwise modify your account. 
+  - [x] [Google MakerSuite/Gemini API](https://ai.google.dev/)
+  - [x] [Azure OpenAI](https://azure.microsoft.com/en-us/products/ai-services/openai-service)
+- [x] Translation from OpenAI-formatted prompts to any other API, including streaming responses
+- [x] Multiple API keys with rotation and rate limit handling
+- [x] Basic user management
+  - [x] Simple role-based permissions
+  - [x] Per-model token quotas
+  - [x] Temporary user accounts
+- [x] Prompt and completion logging
+- [x] Abuse detection and prevention
 
 ---
 
 ## Usage Instructions
-If you'd like to run your own instance of this proxy, you'll need to deploy it somewhere and configure it with your API keys. A few easy options are provided below, though you can also deploy it to any other service you'd like.
+If you'd like to run your own instance of this server, you'll need to deploy it somewhere and configure it with your API keys. A few easy options are provided below, though you can also deploy it to any other service you'd like if you know what you're doing and the service supports Node.js.
 
-### Deploy to Huggingface (Recommended)
+### Self-hosting
+[See here for instructions on how to self-host the application on your own VPS or local machine.](./docs/self-hosting.md)
+
+**Ensure you set the `TRUSTED_PROXIES` environment variable according to your deployment.** Refer to [.env.example](./.env.example) and [config.ts](./src/config.ts) for more information.
+
+### Alternatives
+Fiz and Sekrit are working on some alternative ways to deploy this conveniently. While I'm not involved in this effort beyond providing technical advice regarding my code, I'll link to their work here for convenience: [Sekrit's rentry](https://rentry.org/sekrit)  
+
+### Huggingface (outdated, not advised)
 [See here for instructions on how to deploy to a Huggingface Space.](./docs/deploy-huggingface.md)
 
-### Deploy to Render
+### Render (outdated, not advised)
 [See here for instructions on how to deploy to Render.com.](./docs/deploy-render.md)
 
 ## Local Development
@@ -40,3 +59,12 @@ To run the proxy locally for development or testing, install Node.js >= 18.0.0 a
 4. Start the server in development mode with `npm run start:dev`.
 
 You can also use `npm run start:dev:tsc` to enable project-wide type checking at the cost of slower startup times. `npm run type-check` can be used to run type checking without starting the server.
+
+## Building
+To build the project, run `npm run build`. This will compile the TypeScript code to JavaScript and output it to the `build` directory.
+
+Note that if you are trying to build the server on a very memory-constrained (<= 1GB) VPS, you may need to run the build with `NODE_OPTIONS=--max_old_space_size=2048 npm run build` to avoid running out of memory during the build process, assuming you have swap enabled.  The application itself should run fine on a 512MB VPS for most reasonable traffic levels.
+
+## Forking
+
+If you are forking the repository on GitGud, you may wish to disable GitLab CI/CD or you will be spammed with emails about failed builds due not having any CI runners. You can do this by going to *Settings > General > Visibility, project features, permissions* and then disabling the "CI/CD" feature.

data/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitkeep

docker/ci/.gitlab-ci.yml

@@ -0,0 +1,21 @@
+stages:
+  - build
+
+build_image:
+  stage: build
+  image:
+    name: gcr.io/kaniko-project/executor:debug
+    entrypoint: [""]
+  script:
+    - |
+      if [ "$CI_COMMIT_REF_NAME" = "main" ]; then
+        TAG="latest"
+      else
+        TAG=$CI_COMMIT_REF_NAME
+      fi
+    - echo "Building image with tag $TAG"
+    - BASE64_AUTH=$(echo -n "$DOCKER_HUB_USERNAME:$DOCKER_HUB_ACCESS_TOKEN" | base64)
+    - echo "{\"auths\":{\"https://index.docker.io/v1/\":{\"auth\":\"$BASE64_AUTH\"}}}" > /kaniko/.docker/config.json
+    - /kaniko/executor --context $CI_PROJECT_DIR --dockerfile $CI_PROJECT_DIR/docker/ci/Dockerfile --destination docker.io/khanonci/oai-reverse-proxy:$TAG --build-arg CI_COMMIT_REF_NAME=$CI_COMMIT_REF_NAME --build-arg CI_COMMIT_SHA=$CI_COMMIT_SHA --build-arg CI_PROJECT_PATH=$CI_PROJECT_PATH
+  only:
+    - main

docker/ci/Dockerfile

@@ -0,0 +1,22 @@
+FROM node:18-bullseye-slim
+
+WORKDIR /app
+COPY . .
+
+RUN npm ci
+RUN npm run build
+RUN npm prune --production
+
+EXPOSE 7860
+ENV PORT=7860
+ENV NODE_ENV=production
+
+ARG CI_COMMIT_REF_NAME
+ARG CI_COMMIT_SHA
+ARG CI_PROJECT_PATH
+
+ENV GITGUD_BRANCH=$CI_COMMIT_REF_NAME
+ENV GITGUD_COMMIT=$CI_COMMIT_SHA
+ENV GITGUD_PROJECT=$CI_PROJECT_PATH
+
+CMD [ "npm", "start" ]

docker/docker-compose-selfhost.yml

@@ -0,0 +1,17 @@
+# Before running this, create a .env and greeting.md file.
+# Refer to .env.example for the required environment variables.
+# User-generated content is stored in the data directory.
+# When self-hosting, it's recommended to run this behind a reverse proxy like
+# nginx or Caddy to handle SSL/TLS and rate limiting. Refer to
+# docs/self-hosting.md for more information and an example nginx config.
+version: '3.8'
+services:
+  oai-reverse-proxy:
+    image: khanonci/oai-reverse-proxy:latest
+    ports:
+      - "127.0.0.1:7860:7860"
+    env_file:
+      - ./.env
+    volumes:
+      - ./greeting.md:/app/greeting.md
+      - ./data:/app/data

docker/huggingface/Dockerfile

@@ -3,9 +3,13 @@ RUN apt-get update && \
     apt-get install -y git
 RUN git clone https://gitgud.io/khanon/oai-reverse-proxy.git /app
 WORKDIR /app
+RUN chown -R 1000:1000 /app
+USER 1000
 RUN npm install
 COPY Dockerfile greeting.md* .env* ./
 RUN npm run build
 EXPOSE 7860
 ENV NODE_ENV=production
+# Huggigface free VMs have 16GB of RAM so we can be greedy
+ENV NODE_OPTIONS="--max-old-space-size=12882"
 CMD [ "npm", "start" ]

docs/aws-configuration.md

@@ -0,0 +1,58 @@
+# Configuring the proxy for AWS Bedrock
+
+The proxy supports AWS Bedrock models via the `/proxy/aws/claude` endpoint. There are a few extra steps necessary to use AWS Bedrock compared to the other supported APIs.
+
+- [Setting keys](#setting-keys)
+- [Attaching policies](#attaching-policies)
+- [Provisioning models](#provisioning-models)
+- [Note regarding logging](#note-regarding-logging)
+
+## Setting keys
+
+Use the `AWS_CREDENTIALS` environment variable to set the AWS API keys.
+
+Like other APIs, you can provide multiple keys separated by commas. Each AWS key, however, is a set of credentials including the access key, secret key, and region. These are separated by a colon (`:`).
+
+For example:
+
+```
+AWS_CREDENTIALS=AKIA000000000000000:somesecretkey:us-east-1,AKIA111111111111111:anothersecretkey:us-west-2
+```
+
+## Attaching policies
+
+Unless your credentials belong to the root account, the principal will need to be granted the following permissions:
+
+- `bedrock:InvokeModel`
+- `bedrock:InvokeModelWithResponseStream`
+- `bedrock:GetModelInvocationLoggingConfiguration`
+  - The proxy needs this to determine whether prompt/response logging is enabled. By default, the proxy won't use credentials unless it can conclusively determine that logging is disabled, for privacy reasons.
+
+Use the IAM console or the AWS CLI to attach these policies to the principal associated with the credentials.
+
+## Provisioning models
+
+AWS does not automatically provide accounts with access to every model. You will need to provision the models you want to use, in the regions you want to use them in. You can do this from the AWS console.
+
+⚠️ **Models are region-specific.** Currently AWS only offers Claude in a small number of regions. Switch to the AWS region you want to use, then go to the models page and request access to **Anthropic / Claude**.
+
+![](./assets/aws-request-model-access.png)
+
+Access is generally granted more or less instantly. Once your account has access, you can enable the model by checking the box next to it.
+
+You can also request Claude Instant, but support for this isn't fully implemented yet.
+
+### Supported model IDs
+Users can send these model IDs to the proxy to invoke the corresponding models.
+- **Claude**
+  - `anthropic.claude-v1` (~18k context, claude 1.3 -- EOL 2024-02-28)
+  - `anthropic.claude-v2` (~100k context, claude 2.0)
+  - `anthropic.claude-v2:1` (~200k context, claude 2.1)
+- **Claude Instant**
+  - `anthropic.claude-instant-v1` (~100k context, claude instant 1.2)
+
+## Note regarding logging
+
+By default, the proxy will refuse to use keys if it finds that logging is enabled, or if it doesn't have permission to check logging status.
+
+If you can't attach the `bedrock:GetModelInvocationLoggingConfiguration` policy to the principal, you can set the `ALLOW_AWS_LOGGING` environment variable to `true` to force the proxy to use the keys anyway. A warning will appear on the info page when this is enabled.

docs/azure-configuration.md

@@ -0,0 +1,30 @@
+# Configuring the proxy for Azure
+
+The proxy supports Azure OpenAI Service via the `/proxy/azure/openai` endpoint. The process of setting it up is slightly different from regular OpenAI.
+
+- [Setting keys](#setting-keys)
+- [Model assignment](#model-assignment)
+
+## Setting keys
+
+Use the `AZURE_CREDENTIALS` environment variable to set the Azure API keys.
+
+Like other APIs, you can provide multiple keys separated by commas. Each Azure key, however, is a set of values including the Resource Name, Deployment ID, and API key. These are separated by a colon (`:`).
+
+For example:
+```
+AZURE_CREDENTIALS=contoso-ml:gpt4-8k:0123456789abcdef0123456789abcdef,northwind-corp:testdeployment:0123456789abcdef0123456789abcdef
+```
+
+## Model assignment
+Note that each Azure deployment is assigned a model when you create it in the Azure OpenAI Service portal. If you want to use a different model, you'll need to create a new deployment, and therefore a new key to be added to the AZURE_CREDENTIALS environment variable. Each credential only grants access to one model.
+
+### Supported model IDs
+Users can send normal OpenAI model IDs to the proxy to invoke the corresponding models. For the most part they work the same with Azure. GPT-3.5 Turbo has an ID of "gpt-35-turbo" because Azure doesn't allow periods in model names, but the proxy should automatically convert this to the correct ID.
+
+As noted above, you can only use model IDs for which a deployment has been created and added to the proxy.
+
+## On content filtering
+Be aware that all Azure OpenAI Service deployments have content filtering enabled by default at a Medium level. Prompts or responses which are deemed to be inappropriate will be rejected by the API. This is a feature of the Azure OpenAI Service and not the proxy.
+
+You can disable this from deployment's settings within Azure, but you would need to request an exemption from Microsoft for your organization first. See [this page](https://learn.microsoft.com/en-us/azure/ai-services/openai/how-to/content-filters) for more information.

docs/dall-e-configuration.md

@@ -0,0 +1,71 @@
+# Configuring the proxy for DALL-E
+
+The proxy supports DALL-E 2 and DALL-E 3 image generation via the `/proxy/openai-images` endpoint. By default it is disabled as it is somewhat expensive and potentially more open to abuse than text generation.
+
+- [Updating your Dockerfile](#updating-your-dockerfile)
+- [Enabling DALL-E](#enabling-dall-e)
+- [Setting quotas](#setting-quotas)
+- [Rate limiting](#rate-limiting)
+
+## Updating your Dockerfile
+If you are using a previous version of the Dockerfile supplied with the proxy, it doesn't have the necessary permissions to let the proxy save temporary files.
+
+You can replace the entire thing with the new Dockerfile at [./docker/huggingface/Dockerfile](../docker/huggingface/Dockerfile) (or the equivalent for Render deployments).
+
+You can also modify your existing Dockerfile; just add the following lines after the `WORKDIR` line:
+
+```Dockerfile
+# Existing
+RUN git clone https://gitgud.io/khanon/oai-reverse-proxy.git /app
+WORKDIR /app
+
+# Take ownership of the app directory and switch to the non-root user
+RUN chown -R 1000:1000 /app
+USER 1000
+
+# Existing
+RUN npm install
+```
+
+## Enabling DALL-E
+Add `dall-e` to the `ALLOWED_MODEL_FAMILIES` environment variable to enable DALL-E. For example:
+
+```
+# GPT3.5 Turbo, GPT-4, GPT-4 Turbo, and DALL-E
+ALLOWED_MODEL_FAMILIES=turbo,gpt-4,gpt-4turbo,dall-e
+
+# All models as of this writing
+ALLOWED_MODEL_FAMILIES=turbo,gpt4,gpt4-32k,gpt4-turbo,claude,gemini-pro,aws-claude,dall-e
+```
+
+Refer to [.env.example](../.env.example) for a full list of supported model families. You can add `dall-e` to that list to enable all models.
+
+## Setting quotas
+DALL-E doesn't bill by token like text generation models. Instead there is a fixed cost per image generated, depending on the model, image size, and selected quality.
+
+The proxy still uses tokens to set quotas for users. The cost for each generated image will be converted to "tokens" at a rate of 100000 tokens per US$1.00. This works out to a similar cost-per-token as GPT-4 Turbo, so you can use similar token quotas for both.
+
+Use `TOKEN_QUOTA_DALL_E` to set the default quota for image generation. Otherwise it works the same as token quotas for other models.
+
+```
+# ~50 standard DALL-E images per refresh period, or US$2.00
+TOKEN_QUOTA_DALL_E=200000
+```
+
+Refer to [https://openai.com/pricing](https://openai.com/pricing) for the latest pricing information. As of this writing, the cheapest DALL-E 3 image costs $0.04 per generation, which works out to 4000 tokens. Higher resolution and quality settings can cost up to $0.12 per image, or 12000 tokens. 
+
+## Rate limiting
+The old `MODEL_RATE_LIMIT` setting has been split into `TEXT_MODEL_RATE_LIMIT` and `IMAGE_MODEL_RATE_LIMIT`. Whatever value you previously set for `MODEL_RATE_LIMIT` will be used for text models.
+
+If you don't specify a `IMAGE_MODEL_RATE_LIMIT`, it defaults to half of the `TEXT_MODEL_RATE_LIMIT`, to a minimum of 1 image per minute.
+
+```
+# 4 text generations per minute, 2 images per minute
+TEXT_MODEL_RATE_LIMIT=4
+IMAGE_MODEL_RATE_LIMIT=2
+```
+
+If a prompt is filtered by OpenAI's content filter, it won't count towards the rate limit.
+
+## Hiding recent images
+By default, the proxy shows the last 12 recently generated images by users. You can hide this section by setting `SHOW_RECENT_IMAGES` to `false`.

docs/deploy-huggingface.md

@@ -1,5 +1,7 @@
 # Deploy to Huggingface Space
 
+**⚠️ This method is no longer recommended.  Please use the [self-hosting instructions](./self-hosting.md) instead.**
+
 This repository can be deployed to a [Huggingface Space](https://huggingface.co/spaces).  This is a free service that allows you to run a simple server in the cloud.  You can use it to safely share your OpenAI API key with a friend.
 
 ### 1. Get an API key
@@ -25,11 +27,14 @@ RUN apt-get update && \
     apt-get install -y git
 RUN git clone https://gitgud.io/khanon/oai-reverse-proxy.git /app
 WORKDIR /app
+RUN chown -R 1000:1000 /app
+USER 1000
 RUN npm install
 COPY Dockerfile greeting.md* .env* ./
 RUN npm run build
 EXPOSE 7860
 ENV NODE_ENV=production
+ENV NODE_OPTIONS="--max-old-space-size=12882"
 CMD [ "npm", "start" ]
 ```
 - Click "Commit new file to `main`" to save the Dockerfile.
@@ -88,6 +93,12 @@ See `.env.example` for a full list of available settings, or check `config.ts` f
 
 ## Restricting access to the server
 
-If you want to restrict access to the server, you can set a `PROXY_KEY` secret.  This key will need to be passed in the Authentication header of every request to the server, just like an OpenAI API key.
+If you want to restrict access to the server, you can set a `PROXY_KEY` secret.  This key will need to be passed in the Authentication header of every request to the server, just like an OpenAI API key.  Set the `GATEKEEPER` mode to `proxy_key`, and then set the `PROXY_KEY` variable to whatever password you want.
 
 Add this using the same method as the OPENAI_KEY secret above. Don't add this to your `.env` file because that file is public and anyone can see it.
+
+Example:
+```
+GATEKEEPER=proxy_key
+PROXY_KEY=your_secret_password
+```

docs/deploy-render.md

@@ -1,4 +1,7 @@
 # Deploy to Render.com
+
+**⚠️ This method is no longer recommended.  Please use the [self-hosting instructions](./self-hosting.md) instead.**
+
 Render.com offers a free tier that includes 750 hours of compute time per month.  This is enough to run a single proxy instance 24/7.  Instances shut down after 15 minutes without traffic but start up again automatically when a request is received.  You can use something like https://app.checklyhq.com/ to ping your proxy every 15 minutes to keep it alive.
 
 ### 1. Create account
@@ -28,6 +31,8 @@ The service will be created according to the instructions in the `render.yaml` f
   - For example, `OPENAI_KEY=sk-abc123`.
 - Click **Save Changes**.
 
+**IMPORTANT:** Set `TRUSTED_PROXIES=3`, otherwise users' IP addresses will not be recorded correctly (the server will see the IP address of Render's load balancer instead of the user's real IP address).
+
 The service will automatically rebuild and deploy with the new environment variables.  This will take a few minutes.  The link to your deployed proxy will appear at the top of the page.
 
 If you want to change the URL, go to the **Settings** tab of your Web Service and click the **Edit** button next to **Name**.  You can also set a custom domain, though I haven't tried this yet.

docs/self-hosting.md

@@ -0,0 +1,150 @@
+# Quick self-hosting guide
+
+Temporary guide for self-hosting. This will be improved in the future to provide more robust instructions and options. Provided commands are for Ubuntu.
+
+This uses prebuilt Docker images for convenience. If you want to make adjustments to the code you can instead clone the repo and follow the Local Development guide in the [README](../README.md).
+
+## Table of Contents
+- [Requirements](#requirements)
+- [Running the application](#running-the-application)
+- [Setting up a reverse proxy](#setting-up-a-reverse-proxy)
+  - [trycloudflare](#trycloudflare)
+  - [nginx](#nginx)
+    - [Example basic nginx configuration (no SSL)](#example-basic-nginx-configuration-no-ssl)
+    - [Example with Cloudflare SSL](#example-with-cloudflare-ssl)
+- [Updating/Restarting the application](#updatingrestarting-the-application)
+
+## Requirements
+
+- Docker
+- Docker Compose
+- A VPS with at least 512MB of RAM (1GB recommended)
+- A domain name
+
+If you don't have a VPS and domain name you can use TryCloudflare to set up a temporary URL that you can share with others. See [trycloudflare](#trycloudflare) for more information.
+
+## Running the application
+
+- Install Docker and Docker Compose
+- Create a new directory for the application
+  - This will contain your .env file, greeting file, and any user-generated files
+- Execute the following commands:
+  - ```
+    touch .env
+    touch greeting.md
+    echo "OPENAI_KEY=your-openai-key" >> .env
+    curl https://gitgud.io/khanon/oai-reverse-proxy/-/raw/main/docker/docker-compose-selfhost.yml -o docker-compose.yml
+    ```
+  - You can set further environment variables and keys in the `.env` file. See [.env.example](../.env.example) for a list of available options.
+  - You can set a custom greeting in `greeting.md`. This will be displayed on the homepage.
+- Run `docker compose up -d`
+
+You can check logs with `docker compose logs -n 100 -f`.
+
+The provided docker-compose file listens on port 7860 but binds to localhost only. You should use a reverse proxy to expose the application to the internet as described in the next section.
+
+## Setting up a reverse proxy
+
+Rather than exposing the application directly to the internet, it is recommended to set up a reverse proxy. This will allow you to use HTTPS and add additional security measures.
+
+### trycloudflare
+
+This will give you a temporary (72 hours) URL that you can use to let others connect to your instance securely, without having to set up a reverse proxy. If you are running the server on your home network, this is probably the best option.
+- Install `cloudflared` following the instructions at [try.cloudflare.com](https://try.cloudflare.com/).
+- Run `cloudflared tunnel --url http://localhost:7860`
+- You will be given a temporary URL that you can share with others.
+
+If you have a VPS, you should use a proper reverse proxy like nginx instead for a more permanent solution which will allow you to use your own domain name, handle SSL, and add additional security/anti-abuse measures.
+
+### nginx
+
+First, install nginx.
+- `sudo apt update && sudo apt install nginx`
+
+#### Example basic nginx configuration (no SSL)
+
+- `sudo nano /etc/nginx/sites-available/oai.conf`
+  - ```
+    server {
+        listen 80;
+        server_name example.com;
+    
+        location / {
+            proxy_pass http://localhost:7860;
+        }
+    }
+    ```
+  - Replace `example.com` with your domain name.
+  - Ctrl+X to exit, Y to save, Enter to confirm.
+- `sudo ln -s /etc/nginx/sites-available/oai.conf /etc/nginx/sites-enabled`
+- `sudo nginx -t`
+  - This will check the configuration file for errors.
+- `sudo systemctl restart nginx`
+  - This will restart nginx and apply the new configuration.
+
+#### Example with Cloudflare SSL
+
+This allows you to use a self-signed certificate on the server, and have Cloudflare handle client SSL. You need to have a Cloudflare account and have your domain set up with Cloudflare already, pointing to your server's IP address.
+
+- Set Cloudflare to use Full SSL mode. Since we are using a self-signed certificate, don't use Full (strict) mode.
+- Create a self-signed certificate:
+  - `openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/ssl/private/nginx-selfsigned.key -out /etc/ssl/certs/nginx-selfsigned.crt`
+- `sudo nano /etc/nginx/sites-available/oai.conf`
+  - ```
+    server {
+        listen 443 ssl;
+        server_name yourdomain.com www.yourdomain.com;
+    
+        ssl_certificate /etc/ssl/certs/nginx-selfsigned.crt;
+        ssl_certificate_key /etc/ssl/private/nginx-selfsigned.key;
+    
+        # Only allow inbound traffic from Cloudflare
+        allow 173.245.48.0/20;
+        allow 103.21.244.0/22;
+        allow 103.22.200.0/22;
+        allow 103.31.4.0/22;
+        allow 141.101.64.0/18;
+        allow 108.162.192.0/18;
+        allow 190.93.240.0/20;
+        allow 188.114.96.0/20;
+        allow 197.234.240.0/22;
+        allow 198.41.128.0/17;
+        allow 162.158.0.0/15;
+        allow 104.16.0.0/13;
+        allow 104.24.0.0/14;
+        allow 172.64.0.0/13;
+        allow 131.0.72.0/22;
+        deny all;
+    
+        location / {
+            proxy_pass http://localhost:7860;
+            proxy_http_version 1.1;
+            proxy_set_header Upgrade $http_upgrade;
+            proxy_set_header Connection 'upgrade';
+            proxy_set_header Host $host;
+            proxy_cache_bypass $http_upgrade;
+        }
+    
+        ssl_protocols TLSv1.2 TLSv1.3;
+        ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256';
+        ssl_prefer_server_ciphers on;
+        ssl_session_cache shared:SSL:10m;
+    }
+    ```
+  - Replace `yourdomain.com` with your domain name.
+  - Ctrl+X to exit, Y to save, Enter to confirm.
+- `sudo ln -s /etc/nginx/sites-available/oai.conf /etc/nginx/sites-enabled`
+
+## Updating/Restarting the application
+
+After making an .env change, you need to restart the application for it to take effect.
+
+- `docker compose down`
+- `docker compose up -d`
+
+To update the application to the latest version:
+
+- `docker compose pull`
+- `docker compose down`
+- `docker compose up -d`
+- `docker image prune -f`

http-client.env.json

@@ -0,0 +1,9 @@
+{
+  "dev": {
+    "proxy-host": "http://localhost:7860",
+    "oai-key-1": "override in http-client.private.env.json",
+    "proxy-key": "override in http-client.private.env.json",
+    "azu-resource-name": "override in http-client.private.env.json",
+    "azu-deployment-id": "override in http-client.private.env.json"
+  }
+}

package.json

@@ -4,12 +4,12 @@
   "description": "Reverse proxy for the OpenAI API",
   "scripts": {
     "build": "tsc && copyfiles -u 1 src/**/*.ejs build",
-    "start:dev": "nodemon --watch src --exec ts-node --transpile-only src/server.ts",
+    "prepare": "husky install",
-    "start:watch": "nodemon --require source-map-support/register build/server.js",
-    "start:replit": "tsc && node build/server.js",
     "start": "node build/server.js",
-    "type-check": "tsc --noEmit",
+    "start:dev": "nodemon --watch src --exec ts-node --transpile-only src/server.ts",
-    "prepare": "husky install"
+    "start:replit": "tsc && node build/server.js",
+    "start:watch": "nodemon --require source-map-support/register build/server.js",
+    "type-check": "tsc --noEmit"
   },
   "engines": {
     "node": ">=18.0.0"
@@ -18,12 +18,20 @@
   "license": "MIT",
   "dependencies": {
     "@anthropic-ai/tokenizer": "^0.0.4",
+    "@aws-crypto/sha256-js": "^5.2.0",
+    "@smithy/eventstream-codec": "^2.1.3",
+    "@smithy/eventstream-serde-node": "^2.1.3",
+    "@smithy/protocol-http": "^3.2.1",
+    "@smithy/signature-v4": "^2.1.3",
+    "@smithy/types": "^2.10.1",
+    "@smithy/util-utf8": "^2.1.1",
     "axios": "^1.3.5",
+    "check-disk-space": "^3.4.0",
     "cookie-parser": "^1.4.6",
     "copyfiles": "^2.4.1",
     "cors": "^2.8.5",
     "csrf-csrf": "^2.3.0",
-    "dotenv": "^16.0.3",
+    "dotenv": "^16.3.1",
     "ejs": "^3.1.9",
     "express": "^4.18.2",
     "express-session": "^1.17.3",
@@ -35,12 +43,16 @@
     "node-schedule": "^2.1.1",
     "pino": "^8.11.0",
     "pino-http": "^8.3.3",
-    "sanitize-html": "^2.11.0",
+    "sanitize-html": "2.12.1",
+    "sharp": "^0.32.6",
     "showdown": "^2.1.0",
+    "source-map-support": "^0.5.21",
+    "stream-json": "^1.8.0",
     "tiktoken": "^1.0.10",
     "uuid": "^9.0.0",
     "zlib": "^1.0.5",
-    "zod": "^3.21.4"
+    "zod": "^3.22.3",
+    "zod-error": "^1.5.0"
   },
   "devDependencies": {
     "@types/cookie-parser": "^1.4.3",
@@ -51,17 +63,21 @@
     "@types/node-schedule": "^2.1.0",
     "@types/sanitize-html": "^2.9.0",
     "@types/showdown": "^2.0.0",
+    "@types/stream-json": "^1.7.7",
     "@types/uuid": "^9.0.1",
     "concurrently": "^8.0.1",
     "esbuild": "^0.17.16",
     "esbuild-register": "^3.4.2",
     "husky": "^8.0.3",
     "nodemon": "^3.0.1",
-    "source-map-support": "^0.5.21",
+    "pino-pretty": "^10.2.3",
+    "prettier": "^3.0.3",
     "ts-node": "^10.9.1",
-    "typescript": "^5.0.4"
+    "typescript": "^5.4.2"
   },
   "overrides": {
-    "google-gax": "^3.6.1"
+    "google-gax": "^3.6.1",
+    "postcss": "^8.4.31",
+    "follow-redirects": "^1.15.4"
   }
 }

scripts/oai-reverse-proxy.http

@@ -0,0 +1,276 @@
+# OAI Reverse Proxy
+
+###
+# @name OpenAI -- Chat Completions
+POST https://api.openai.com/v1/chat/completions
+Authorization: Bearer {{oai-key-1}}
+Content-Type: application/json
+
+{
+  "model": "gpt-3.5-turbo",
+  "max_tokens": 30,
+  "stream": false,
+  "messages": [
+    {
+      "role": "user",
+      "content": "This is a test prompt."
+    }
+  ]
+}
+
+###
+# @name OpenAI -- Text Completions
+POST https://api.openai.com/v1/completions
+Authorization: Bearer {{oai-key-1}}
+Content-Type: application/json
+
+{
+  "model": "gpt-3.5-turbo-instruct",
+  "max_tokens": 30,
+  "stream": false,
+  "prompt": "This is a test prompt where"
+}
+
+###
+# @name OpenAI -- Create Embedding
+POST https://api.openai.com/v1/embeddings
+Authorization: Bearer {{oai-key-1}}
+Content-Type: application/json
+
+{
+  "model": "text-embedding-ada-002",
+  "input": "This is a test embedding input."
+}
+
+###
+# @name OpenAI -- Get Organizations
+GET https://api.openai.com/v1/organizations
+Authorization: Bearer {{oai-key-1}}
+
+###
+# @name OpenAI -- Get Models
+GET https://api.openai.com/v1/models
+Authorization: Bearer {{oai-key-1}}
+
+###
+# @name Azure OpenAI -- Chat Completions
+POST https://{{azu-resource-name}}.openai.azure.com/openai/deployments/{{azu-deployment-id}}/chat/completions?api-version=2023-09-01-preview
+api-key: {{azu-key-1}}
+Content-Type: application/json
+
+{
+  "max_tokens": 1,
+  "stream": false,
+  "messages": [
+    {
+      "role": "user",
+      "content": "This is a test prompt."
+    }
+  ]
+}
+
+###
+# @name Proxy / OpenAI -- Get Models
+GET {{proxy-host}}/proxy/openai/v1/models
+Authorization: Bearer {{proxy-key}}
+
+###
+# @name Proxy / OpenAI -- Native Chat Completions
+POST {{proxy-host}}/proxy/openai/chat/completions
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "gpt-4-1106-preview",
+  "max_tokens": 20,
+  "stream": true,
+  "temperature": 1,
+  "seed": 123,
+  "messages": [
+    {
+      "role": "user",
+      "content": "phrase one"
+    }
+  ]
+}
+
+###
+# @name Proxy / OpenAI -- Native Text Completions
+POST {{proxy-host}}/proxy/openai/v1/turbo-instruct/chat/completions
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "gpt-3.5-turbo-instruct",
+  "max_tokens": 20,
+  "temperature": 0,
+  "prompt": "Genshin Impact is a game about",
+  "stream": false
+}
+
+###
+# @name Proxy / OpenAI -- Chat-to-Text API Translation
+# Accepts a chat completion request and reformats it to work with the text completion API. `model` is ignored.
+POST {{proxy-host}}/proxy/openai/turbo-instruct/chat/completions
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "gpt-4",
+  "max_tokens": 20,
+  "stream": true,
+  "messages": [
+    {
+      "role": "user",
+      "content": "What is the name of the fourth president of the united states?"
+    },
+    {
+      "role": "assistant",
+      "content": "That would be George Washington."
+    },
+    {
+      "role": "user",
+      "content": "I don't think that's right..."
+    }
+  ]
+}
+
+###
+# @name Proxy / OpenAI -- Create Embedding
+POST {{proxy-host}}/proxy/openai/embeddings
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "text-embedding-ada-002",
+  "input": "This is a test embedding input."
+}
+
+
+###
+# @name Proxy / Anthropic -- Native Completion (old API)
+POST {{proxy-host}}/proxy/anthropic/v1/complete
+Authorization: Bearer {{proxy-key}}
+anthropic-version: 2023-01-01
+Content-Type: application/json
+
+{
+  "model": "claude-v1.3",
+  "max_tokens_to_sample": 20,
+  "temperature": 0.2,
+  "stream": true,
+  "prompt": "What is genshin impact\n\n:Assistant:"
+}
+
+###
+# @name Proxy / Anthropic -- Native Completion (2023-06-01 API)
+POST {{proxy-host}}/proxy/anthropic/v1/complete
+Authorization: Bearer {{proxy-key}}
+anthropic-version: 2023-06-01
+Content-Type: application/json
+
+{
+  "model": "claude-v1.3",
+  "max_tokens_to_sample": 20,
+  "temperature": 0.2,
+  "stream": true,
+  "prompt": "What is genshin impact\n\n:Assistant:"
+}
+
+###
+# @name Proxy / Anthropic -- OpenAI-to-Anthropic API Translation
+POST {{proxy-host}}/proxy/anthropic/v1/chat/completions
+Authorization: Bearer {{proxy-key}}
+#anthropic-version: 2023-06-01
+Content-Type: application/json
+
+{
+  "model": "gpt-3.5-turbo",
+  "max_tokens": 20,
+  "stream": false,
+  "temperature": 0,
+  "messages": [
+    {
+      "role": "user",
+      "content": "What is genshin impact"
+    }
+  ]
+}
+
+###
+# @name Proxy / AWS Claude -- Native Completion
+POST {{proxy-host}}/proxy/aws/claude/v1/complete
+Authorization: Bearer {{proxy-key}}
+anthropic-version: 2023-01-01
+Content-Type: application/json
+
+{
+  "model": "claude-v2",
+  "max_tokens_to_sample": 10,
+  "temperature": 0,
+  "stream": true,
+  "prompt": "What is genshin impact\n\n:Assistant:"
+}
+
+###
+# @name Proxy / AWS Claude -- OpenAI-to-Anthropic API Translation
+POST {{proxy-host}}/proxy/aws/claude/chat/completions
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "gpt-3.5-turbo",
+  "max_tokens": 50,
+  "stream": true,
+  "messages": [
+    {
+      "role": "user",
+      "content": "What is genshin impact?"
+    }
+  ]
+}
+
+###
+# @name Proxy / Azure OpenAI -- Native Chat Completions
+POST {{proxy-host}}/proxy/azure/openai/chat/completions
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "gpt-4",
+  "max_tokens": 20,
+  "stream": true,
+  "temperature": 1,
+  "seed": 2,
+  "messages": [
+    {
+      "role": "user",
+      "content": "Hi what is the name of the fourth president of the united states?"
+    },
+    {
+      "role": "assistant",
+      "content": "That would be George Washington."
+    },
+    {
+      "role": "user",
+      "content": "That's not right."
+    }
+  ]
+}
+
+###
+# @name Proxy / Google AI -- OpenAI-to-Google AI API Translation
+POST {{proxy-host}}/proxy/google-ai/v1/chat/completions
+Authorization: Bearer {{proxy-key}}
+Content-Type: application/json
+
+{
+  "model": "gpt-4",
+  "max_tokens": 42,
+  "messages": [
+    {
+      "role": "user",
+      "content": "Hi what is the name of the fourth president of the united states?"
+    }
+  ]
+}

scripts/test-concurrency.js

@@ -0,0 +1,45 @@
+const axios = require("axios");
+
+const concurrentRequests = 75;
+const headers = {
+  Authorization: "Bearer test",
+  "Content-Type": "application/json",
+};
+
+const payload = {
+  model: "gpt-4",
+  max_tokens: 1,
+  stream: false,
+  messages: [{ role: "user", content: "Hi" }],
+};
+
+const makeRequest = async (i) => {
+  try {
+    const response = await axios.post(
+      "http://localhost:7860/proxy/google-ai/v1/chat/completions",
+      payload,
+      { headers }
+    );
+    console.log(
+      `Req ${i} finished with status code ${response.status} and response:`,
+      response.data
+    );
+  } catch (error) {
+    const msg = error.response
+    console.error(`Error in req ${i}:`, error.message, msg || "");
+  }
+};
+
+const executeRequestsConcurrently = () => {
+  const promises = [];
+  for (let i = 1; i <= concurrentRequests; i++) {
+    console.log(`Starting request ${i}`);
+    promises.push(makeRequest(i));
+  }
+
+  Promise.all(promises).then(() => {
+    console.log("All requests finished");
+  });
+};
+
+executeRequestsConcurrently();

src/admin/routes.ts

@@ -4,6 +4,8 @@ import { HttpError } from "../shared/errors";
 import { injectLocals } from "../shared/inject-locals";
 import { withSession } from "../shared/with-session";
 import { injectCsrfToken, checkCsrfToken } from "../shared/inject-csrf";
+import { renderPage } from "../info-page";
+import { buildInfo } from "../service-info";
 import { loginRouter } from "./login";
 import { usersApiRouter as apiRouter } from "./api/users";
 import { usersWebRouter as webRouter } from "./web/manage";
@@ -23,6 +25,11 @@ adminRouter.use(checkCsrfToken);
 adminRouter.use(injectLocals);
 adminRouter.use("/", loginRouter);
 adminRouter.use("/manage", authorize({ via: "cookie" }), webRouter);
+adminRouter.use("/service-info", authorize({ via: "cookie" }), (req, res) => {
+  return res.send(
+    renderPage(buildInfo(req.protocol + "://" + req.get("host"), true))
+  );
+});
 
 adminRouter.use(
   (

src/admin/web/manage.ts

@@ -6,7 +6,7 @@ import { HttpError } from "../../shared/errors";
 import * as userStore from "../../shared/users/user-store";
 import { parseSort, sortBy, paginate } from "../../shared/utils";
 import { keyPool } from "../../shared/key-management";
-import { MODEL_FAMILIES } from "../../shared/models";
+import { LLMService, MODEL_FAMILIES } from "../../shared/models";
 import { getTokenCostUsd, prettyTokens } from "../../shared/stats";
 import {
   User,
@@ -14,6 +14,7 @@ import {
   UserSchema,
   UserTokenCounts,
 } from "../../shared/users/schema";
+import { getLastNImages } from "../../shared/file-storage/image-history";
 
 const router = Router();
 
@@ -196,13 +197,14 @@ router.post("/maintenance", (req, res) => {
   let flash = { type: "", message: "" };
   switch (action) {
     case "recheck": {
-      keyPool.recheck("openai");
+      const checkable: LLMService[] = ["openai", "anthropic", "aws", "azure"];
-      keyPool.recheck("anthropic");
+      checkable.forEach((s) => keyPool.recheck(s));
-      const size = keyPool
+      const keyCount = keyPool
         .list()
-        .filter((k) => k.service !== "google-palm").length;
+        .filter((k) => checkable.includes(k.service)).length;
+
       flash.type = "success";
-      flash.message = `Scheduled recheck of ${size} keys for OpenAI and Anthropic.`;
+      flash.message = `Scheduled recheck of ${keyCount} keys.`;
       break;
     }
     case "resetQuotas": {
@@ -220,6 +222,18 @@ router.post("/maintenance", (req, res) => {
       flash.message = `All users' token usage records reset.`;
       break;
     }
+    case "downloadImageMetadata": {
+      const data = JSON.stringify({
+        exportedAt: new Date().toISOString(),
+        generations: getLastNImages()
+      }, null, 2);
+      res.setHeader(
+        "Content-Disposition",
+        `attachment; filename=image-metadata-${new Date().toISOString()}.json`
+      );
+      res.setHeader("Content-Type", "application/json");
+      return res.send(data);
+    }
     default: {
       throw new HttpError(400, "Invalid action");
     }

src/admin/web/views/admin_index.ejs

@@ -1,5 +1,11 @@
 <%- include("partials/shared_header", { title: "OAI Reverse Proxy Admin" }) %>
 <h1>OAI Reverse Proxy Admin</h1>
+<% if (!usersEnabled) { %>
+<p style="color: red; background-color: #eedddd; padding: 1em">
+  <strong>🚨 <code>user_token</code> gatekeeper is not enabled.</strong><br />
+  <br />None of the user management features will do anything.
+</p>
+<% } %>
 <% if (!persistenceEnabled) { %>
 <p style="color: red; background-color: #eedddd; padding: 1em">
   <strong>⚠️ Users will be lost when the server restarts because persistence is not configured.</strong><br />
@@ -19,6 +25,7 @@
   <li><a href="/admin/manage/import-users">Import Users</a></li>
   <li><a href="/admin/manage/export-users">Export Users</a></li>
   <li><a href="/admin/manage/download-stats">Download Rentry Stats</a>
+  <li><a href="/admin/service-info">Service Info</a></li>
 </ul>
 <h3>Maintenance</h3>
 <form id="maintenanceForm" action="/admin/manage/maintenance" method="post">
@@ -43,6 +50,13 @@
       </p>
     </fieldset>
     <% } %>
+    <% if (imageGenerationEnabled) { %>
+    <fieldset>
+      <legend>Image Generation</legend>
+      <button id="download-image-metadata" type="button" onclick="submitForm('downloadImageMetadata')">Download Image Metadata</button>
+      <label for="download-image-metadata">Downloads a metadata file containing URL, prompt, and truncated user token for all cached images.</label>
+    </fieldset>
+    <% } %>
   </div>
 </form>
 

src/admin/web/views/admin_list-users.ejs

@@ -6,7 +6,7 @@
     <% } else { %>
     <input type="checkbox" id="toggle-nicknames" onchange="toggleNicknames()" />
     <label for="toggle-nicknames">Show Nicknames</label>
-    <table>
+    <table class="striped">
       <thead>
         <tr>
           <th>User</th>

src/config.ts

@@ -1,25 +1,60 @@
 import dotenv from "dotenv";
 import type firebase from "firebase-admin";
+import path from "path";
 import pino from "pino";
 import type { ModelFamily } from "./shared/models";
+import { MODEL_FAMILIES } from "./shared/models";
+
 dotenv.config();
 
-// Can't import the usual logger here because it itself needs the config.
 const startupLogger = pino({ level: "debug" }).child({ module: "startup" });
-
 const isDev = process.env.NODE_ENV !== "production";
 
-type PromptLoggingBackend = "google_sheets";
+export const DATA_DIR = path.join(__dirname, "..", "data");
+export const USER_ASSETS_DIR = path.join(DATA_DIR, "user-files");
 
 type Config = {
   /** The port the proxy server will listen on. */
   port: number;
+  /** The network interface the proxy server will listen on. */
+  bindAddress: string;
   /** Comma-delimited list of OpenAI API keys. */
   openaiKey?: string;
   /** Comma-delimited list of Anthropic API keys. */
   anthropicKey?: string;
-  /** Comma-delimited list of Google PaLM API keys. */
+  /**
-  googlePalmKey?: string;
+   * Comma-delimited list of Google AI API keys. Note that these are not the
+   * same as the GCP keys/credentials used for Vertex AI; the models are the
+   * same but the APIs are different. Vertex is the GCP product for enterprise.
+   **/
+  googleAIKey?: string;
+  /**
+   * Comma-delimited list of Mistral AI API keys.
+   */
+  mistralAIKey?: string;
+  /**
+   * Comma-delimited list of AWS credentials. Each credential item should be a
+   * colon-delimited list of access key, secret key, and AWS region.
+   *
+   * The credentials must have access to the actions `bedrock:InvokeModel` and
+   * `bedrock:InvokeModelWithResponseStream`. You must also have already
+   * provisioned the necessary models in your AWS account, on the specific
+   * regions specified for each credential. Models are region-specific.
+   *
+   * @example `AWS_CREDENTIALS=access_key_1:secret_key_1:us-east-1,access_key_2:secret_key_2:us-west-2`
+   */
+  awsCredentials?: string;
+  /**
+   * Comma-delimited list of Azure OpenAI credentials. Each credential item
+   * should be a colon-delimited list of Azure resource name, deployment ID, and
+   * API key.
+   *
+   * The resource name is the subdomain in your Azure OpenAI deployment's URL,
+   * e.g. `https://resource-name.openai.azure.com
+   *
+   * @example `AZURE_CREDENTIALS=resource_name_1:deployment_id_1:api_key_1,resource_name_2:deployment_id_2:api_key_2`
+   */
+  azureCredentials?: string;
   /**
    * The proxy key to require for requests. Only applicable if the user
    * management mode is set to 'proxy_key', and required if so.
@@ -30,6 +65,11 @@ type Config = {
    * management mode is set to 'user_token'.
    */
   adminKey?: string;
+  /**
+   * The password required to view the service info/status page. If not set, the
+   * info page will be publicly accessible.
+   */
+  serviceInfoPassword?: string;
   /**
    * Which user management mode to use.
    * - `none`: No user management. Proxy is open to all requests with basic
@@ -57,13 +97,20 @@ type Config = {
    */
   firebaseKey?: string;
   /**
-   * Maximum number of IPs per user, after which their token is disabled.
+   * Maximum number of IPs allowed per user token.
    * Users with the manually-assigned `special` role are exempt from this limit.
    * - Defaults to 0, which means that users are not IP-limited.
    */
   maxIpsPerUser: number;
-  /** Per-IP limit for requests per minute to OpenAI's completions endpoint. */
+  /**
-  modelRateLimit: number;
+   * Whether a user token should be automatically disabled if it exceeds the
+   * `maxIpsPerUser` limit, or if only connections from new IPs are be rejected.
+   */
+  maxIpsAutoBan: boolean;
+  /** Per-IP limit for requests per minute to text and chat models. */
+  textModelRateLimit: number;
+  /** Per-IP limit for requests per minute to image generation models. */
+  imageModelRateLimit: number;
   /**
    * For OpenAI, the maximum number of context tokens (prompt + max output) a
    * user can request before their request is rejected.
@@ -82,16 +129,27 @@ type Config = {
   maxOutputTokensOpenAI: number;
   /** For Anthropic, the maximum number of sampled tokens a user can request. */
   maxOutputTokensAnthropic: number;
-  /** Whether requests containing disallowed characters should be rejected. */
+  /** Whether requests containing the following phrases should be rejected. */
-  rejectDisallowed?: boolean;
+  rejectPhrases: string[];
   /** Message to return when rejecting requests. */
-  rejectMessage?: string;
+  rejectMessage: string;
   /** Verbosity level of diagnostic logging. */
   logLevel: "trace" | "debug" | "info" | "warn" | "error";
+  /**
+   * Whether to allow the usage of AWS credentials which could be logging users'
+   * model invocations. By default, such keys are treated as if they were
+   * disabled because users may not be aware that their usage is being logged.
+   *
+   * Some credentials do not have the policy attached that allows the proxy to
+   * confirm logging status, in which case the proxy assumes that logging could
+   * be enabled and will refuse to use the key. If you still want to use such a
+   * key and can't attach the policy, you can set this to true.
+   */
+  allowAwsLogging?: boolean;
   /** Whether prompts and responses should be logged to persistent storage. */
   promptLogging?: boolean;
   /** Which prompt logging backend to use. */
-  promptLoggingBackend?: PromptLoggingBackend;
+  promptLoggingBackend?: "google_sheets";
   /** Base64-encoded Google Sheets API key. */
   googleSheetsKey?: string;
   /** Google Sheets spreadsheet ID. */
@@ -110,7 +168,7 @@ type Config = {
   blockedOrigins?: string;
   /** Message to return when rejecting requests from blocked origins. */
   blockMessage?: string;
-  /** Desination URL to redirect blocked requests to, for non-JSON requests. */
+  /** Destination URL to redirect blocked requests to, for non-JSON requests. */
   blockRedirect?: string;
   /** Which model families to allow requests for. Applies only to OpenAI. */
   allowedModelFamilies: ModelFamily[];
@@ -133,31 +191,101 @@ type Config = {
   quotaRefreshPeriod?: "hourly" | "daily" | string;
   /** Whether to allow users to change their own nicknames via the UI. */
   allowNicknameChanges: boolean;
+  /** Whether to show recent DALL-E image generations on the homepage. */
+  showRecentImages: boolean;
+  /**
+   * If true, cookies will be set without the `Secure` attribute, allowing
+   * the admin UI to used over HTTP.
+   */
+  useInsecureCookies: boolean;
+  /**
+   * Whether to use a more minimal public Service Info page with static content.
+   * Disables all stats pertaining to traffic, prompt/token usage, and queues.
+   * The full info page will appear if you have signed in as an admin using the
+   * configured ADMIN_KEY and go to /admin/service-info.
+   **/
+  staticServiceInfo?: boolean;
+  /**
+   * Trusted proxy hops. If you are deploying the server behind a reverse proxy
+   * (Nginx, Cloudflare Tunnel, AWS WAF, etc.) the IP address of incoming
+   * requests will be the IP address of the proxy, not the actual user.
+   *
+   * Depending on your hosting configuration, there may be multiple proxies/load
+   * balancers between your server and the user. Each one will append the
+   * incoming IP address to the `X-Forwarded-For` header. The user's real IP
+   * address will be the first one in the list, assuming the header has not been
+   * tampered with. Setting this value correctly ensures that the server doesn't
+   * trust values in `X-Forwarded-For` not added by trusted proxies.
+   *
+   * In order for the server to determine the user's real IP address, you need
+   * to tell it how many proxies are between the user and the server so it can
+   * select the correct IP address from the `X-Forwarded-For` header.
+   *
+   * *WARNING:* If you set it incorrectly, the proxy will either record the
+   * wrong IP address, or it will be possible for users to spoof their IP
+   * addresses and bypass rate limiting. Check the request logs to see what
+   * incoming X-Forwarded-For values look like.
+   *
+   * Examples:
+   *  - X-Forwarded-For: "34.1.1.1, 172.1.1.1, 10.1.1.1" => trustedProxies: 3
+   *  - X-Forwarded-For: "34.1.1.1" => trustedProxies: 1
+   *  - no X-Forwarded-For header => trustedProxies: 0 (the actual IP of the incoming request will be used)
+   *
+   * As of 2024/01/08:
+   * For HuggingFace or Cloudflare Tunnel, use 1.
+   * For Render, use 3.
+   * For deployments not behind a load balancer, use 0.
+   *
+   * You should double check against your actual request logs to be sure.
+   *
+   * Defaults to 1, as most deployments are on HuggingFace or Cloudflare Tunnel.
+   */
+  trustedProxies?: number;
+  /**
+   * Whether to allow OpenAI tool usage.  The proxy doesn't impelment any
+   * support for tools/function calling but can pass requests and responses as
+   * is. Note that the proxy also cannot accurately track quota usage for
+   * requests involving tools, so you must opt in to this feature at your own
+   * risk.
+   */
+  allowOpenAIToolUsage?: boolean;
+  /**
+   * Allows overriding the default proxy endpoint route. Defaults to /proxy.
+   * A leading slash is required.
+   */
+  proxyEndpointRoute: string;
 };
 
 // To change configs, create a file called .env in the root directory.
 // See .env.example for an example.
 export const config: Config = {
   port: getEnvWithDefault("PORT", 7860),
+  bindAddress: getEnvWithDefault("BIND_ADDRESS", "0.0.0.0"),
   openaiKey: getEnvWithDefault("OPENAI_KEY", ""),
   anthropicKey: getEnvWithDefault("ANTHROPIC_KEY", ""),
-  googlePalmKey: getEnvWithDefault("GOOGLE_PALM_KEY", ""),
+  googleAIKey: getEnvWithDefault("GOOGLE_AI_KEY", ""),
+  mistralAIKey: getEnvWithDefault("MISTRAL_AI_KEY", ""),
+  awsCredentials: getEnvWithDefault("AWS_CREDENTIALS", ""),
+  azureCredentials: getEnvWithDefault("AZURE_CREDENTIALS", ""),
   proxyKey: getEnvWithDefault("PROXY_KEY", ""),
   adminKey: getEnvWithDefault("ADMIN_KEY", ""),
+  serviceInfoPassword: getEnvWithDefault("SERVICE_INFO_PASSWORD", ""),
   gatekeeper: getEnvWithDefault("GATEKEEPER", "none"),
   gatekeeperStore: getEnvWithDefault("GATEKEEPER_STORE", "memory"),
   maxIpsPerUser: getEnvWithDefault("MAX_IPS_PER_USER", 0),
+  maxIpsAutoBan: getEnvWithDefault("MAX_IPS_AUTO_BAN", true),
   firebaseRtdbUrl: getEnvWithDefault("FIREBASE_RTDB_URL", undefined),
   firebaseKey: getEnvWithDefault("FIREBASE_KEY", undefined),
-  modelRateLimit: getEnvWithDefault("MODEL_RATE_LIMIT", 4),
+  textModelRateLimit: getEnvWithDefault("TEXT_MODEL_RATE_LIMIT", 4),
-  maxContextTokensOpenAI: getEnvWithDefault("MAX_CONTEXT_TOKENS_OPENAI", 0),
+  imageModelRateLimit: getEnvWithDefault("IMAGE_MODEL_RATE_LIMIT", 4),
+  maxContextTokensOpenAI: getEnvWithDefault("MAX_CONTEXT_TOKENS_OPENAI", 16384),
   maxContextTokensAnthropic: getEnvWithDefault(
     "MAX_CONTEXT_TOKENS_ANTHROPIC",
     0
   ),
   maxOutputTokensOpenAI: getEnvWithDefault(
     ["MAX_OUTPUT_TOKENS_OPENAI", "MAX_OUTPUT_TOKENS"],
-    300
+    400
   ),
   maxOutputTokensAnthropic: getEnvWithDefault(
     ["MAX_OUTPUT_TOKENS_ANTHROPIC", "MAX_OUTPUT_TOKENS"],
@@ -167,9 +295,21 @@ export const config: Config = {
     "turbo",
     "gpt4",
     "gpt4-32k",
+    "gpt4-turbo",
     "claude",
+    "claude-opus",
+    "gemini-pro",
+    "mistral-tiny",
+    "mistral-small",
+    "mistral-medium",
+    "mistral-large",
+    "aws-claude",
+    "azure-turbo",
+    "azure-gpt4",
+    "azure-gpt4-turbo",
+    "azure-gpt4-32k",
   ]),
-  rejectDisallowed: getEnvWithDefault("REJECT_DISALLOWED", false),
+  rejectPhrases: parseCsv(getEnvWithDefault("REJECT_PHRASES", "")),
   rejectMessage: getEnvWithDefault(
     "REJECT_MESSAGE",
     "This content violates /aicg/'s acceptable use policy."
@@ -177,6 +317,7 @@ export const config: Config = {
   logLevel: getEnvWithDefault("LOG_LEVEL", "info"),
   checkKeys: getEnvWithDefault("CHECK_KEYS", !isDev),
   showTokenCosts: getEnvWithDefault("SHOW_TOKEN_COSTS", false),
+  allowAwsLogging: getEnvWithDefault("ALLOW_AWS_LOGGING", false),
   promptLogging: getEnvWithDefault("PROMPT_LOGGING", false),
   promptLoggingBackend: getEnvWithDefault("PROMPT_LOGGING_BACKEND", undefined),
   googleSheetsKey: getEnvWithDefault("GOOGLE_SHEETS_KEY", undefined),
@@ -190,15 +331,24 @@ export const config: Config = {
     "You must be over the age of majority in your country to use this service."
   ),
   blockRedirect: getEnvWithDefault("BLOCK_REDIRECT", "https://www.9gag.com"),
-  tokenQuota: {
+  tokenQuota: MODEL_FAMILIES.reduce(
-    turbo: getEnvWithDefault("TOKEN_QUOTA_TURBO", 0),
+    (acc, family: ModelFamily) => {
-    gpt4: getEnvWithDefault("TOKEN_QUOTA_GPT4", 0),
+      acc[family] = getEnvWithDefault(
-    "gpt4-32k": getEnvWithDefault("TOKEN_QUOTA_GPT4_32K", 0),
+        `TOKEN_QUOTA_${family.toUpperCase().replace(/-/g, "_")}`,
-    claude: getEnvWithDefault("TOKEN_QUOTA_CLAUDE", 0),
+        0
-    bison: getEnvWithDefault("TOKEN_QUOTA_BISON", 0),
+      ) as number;
-  },
+      return acc;
+    },
+    {} as { [key in ModelFamily]: number }
+  ),
   quotaRefreshPeriod: getEnvWithDefault("QUOTA_REFRESH_PERIOD", undefined),
   allowNicknameChanges: getEnvWithDefault("ALLOW_NICKNAME_CHANGES", true),
+  showRecentImages: getEnvWithDefault("SHOW_RECENT_IMAGES", true),
+  useInsecureCookies: getEnvWithDefault("USE_INSECURE_COOKIES", isDev),
+  staticServiceInfo: getEnvWithDefault("STATIC_SERVICE_INFO", false),
+  trustedProxies: getEnvWithDefault("TRUSTED_PROXIES", 1),
+  allowOpenAIToolUsage: getEnvWithDefault("ALLOW_OPENAI_TOOL_USAGE", false),
+  proxyEndpointRoute: getEnvWithDefault("PROXY_ENDPOINT_ROUTE", "/proxy"),
 } as const;
 
 function generateCookieSecret() {
@@ -214,12 +364,16 @@ function generateCookieSecret() {
 export const COOKIE_SECRET = generateCookieSecret();
 
 export async function assertConfigIsValid() {
-  if (process.env.TURBO_ONLY === "true") {
+  if (process.env.MODEL_RATE_LIMIT !== undefined) {
+    const limit =
+      parseInt(process.env.MODEL_RATE_LIMIT, 10) || config.textModelRateLimit;
+
+    config.textModelRateLimit = limit;
+    config.imageModelRateLimit = Math.max(Math.floor(limit / 2), 1);
+
     startupLogger.warn(
-      "TURBO_ONLY is deprecated. Use ALLOWED_MODEL_FAMILIES=turbo instead."
+      { textLimit: limit, imageLimit: config.imageModelRateLimit },
-    );
+      "MODEL_RATE_LIMIT is deprecated. Use TEXT_MODEL_RATE_LIMIT and IMAGE_MODEL_RATE_LIMIT instead."
-    config.allowedModelFamilies = config.allowedModelFamilies.filter(
-      (f) => !f.includes("gpt4")
     );
   }
 
@@ -260,7 +414,8 @@ export async function assertConfigIsValid() {
   // them to users.
   for (const key of getKeys(config)) {
     const maybeSensitive = ["key", "credentials", "secret", "password"].some(
-      (sensitive) => key.toLowerCase().includes(sensitive)
+      (sensitive) =>
+        key.toLowerCase().includes(sensitive) && !["checkKeys"].includes(key)
     );
     const secured = new Set([...SENSITIVE_KEYS, ...OMITTED_KEYS]);
     if (maybeSensitive && !secured.has(key))
@@ -282,15 +437,21 @@ export const SENSITIVE_KEYS: (keyof Config)[] = ["googleSheetsSpreadsheetId"];
  * Config keys that are not displayed on the info page at all, generally because
  * they are not relevant to the user or can be inferred from other config.
  */
-export const OMITTED_KEYS: (keyof Config)[] = [
+export const OMITTED_KEYS = [
   "port",
+  "bindAddress",
   "logLevel",
   "openaiKey",
   "anthropicKey",
-  "googlePalmKey",
+  "googleAIKey",
+  "mistralAIKey",
+  "awsCredentials",
+  "azureCredentials",
   "proxyKey",
   "adminKey",
-  "checkKeys",
+  "serviceInfoPassword",
+  "rejectPhrases",
+  "rejectMessage",
   "showTokenCosts",
   "googleSheetsKey",
   "firebaseKey",
@@ -301,34 +462,53 @@ export const OMITTED_KEYS: (keyof Config)[] = [
   "blockMessage",
   "blockRedirect",
   "allowNicknameChanges",
-];
+  "showRecentImages",
+  "useInsecureCookies",
+  "staticServiceInfo",
+  "checkKeys",
+  "allowedModelFamilies",
+  "trustedProxies",
+  "proxyEndpointRoute",
+] satisfies (keyof Config)[];
+type OmitKeys = (typeof OMITTED_KEYS)[number];
+
+type Printable<T> = {
+  [P in keyof T as Exclude<P, OmitKeys>]: T[P] extends object
+    ? Printable<T[P]>
+    : string;
+};
+type PublicConfig = Printable<Config>;
 
 const getKeys = Object.keys as <T extends object>(obj: T) => Array<keyof T>;
 
-export function listConfig(obj: Config = config): Record<string, any> {
+export function listConfig(obj: Config = config) {
-  const result: Record<string, any> = {};
+  const result: Record<string, unknown> = {};
   for (const key of getKeys(obj)) {
     const value = obj[key]?.toString() || "";
 
-    const shouldOmit =
-      OMITTED_KEYS.includes(key) || value === "" || value === "undefined";
     const shouldMask = SENSITIVE_KEYS.includes(key);
+    const shouldOmit =
+      OMITTED_KEYS.includes(key as OmitKeys) ||
+      value === "" ||
+      value === "undefined";
 
     if (shouldOmit) {
       continue;
     }
 
+    const validKey = key as keyof Printable<Config>;
+
     if (value && shouldMask) {
-      result[key] = "********";
+      result[validKey] = "********";
     } else {
-      result[key] = value;
+      result[validKey] = value;
     }
 
     if (typeof obj[key] === "object" && !Array.isArray(obj[key])) {
       result[key] = listConfig(obj[key] as unknown as Config);
     }
   }
-  return result;
+  return result as PublicConfig;
 }
 
 /**
@@ -344,7 +524,13 @@ function getEnvWithDefault<T>(env: string | string[], defaultValue: T): T {
   }
   try {
     if (
-      ["OPENAI_KEY", "ANTHROPIC_KEY", "GOOGLE_PALM_KEY"].includes(String(env))
+      [
+        "OPENAI_KEY",
+        "ANTHROPIC_KEY",
+        "GOOGLE_AI_KEY",
+        "AWS_CREDENTIALS",
+        "AZURE_CREDENTIALS",
+      ].includes(String(env))
     ) {
       return value as unknown as T;
     }
@@ -385,3 +571,11 @@ export function getFirebaseApp(): firebase.app.App {
   }
   return firebaseApp;
 }
+
+function parseCsv(val: string): string[] {
+  if (!val) return [];
+
+  const regex = /(".*?"|[^",]+)(?=\s*,|\s*$)/g;
+  const matches = val.match(regex) || [];
+  return matches.map((item) => item.replace(/^"|"$/g, "").trim());
+}

src/info-page.ts

@@ -1,128 +1,90 @@
+/** This whole module kinda sucks */
 import fs from "fs";
-import { Request, Response } from "express";
+import express, { Router, Request, Response } from "express";
 import showdown from "showdown";
-import { config, listConfig } from "./config";
+import { config } from "./config";
-import {
+import { buildInfo, ServiceInfo } from "./service-info";
-  AnthropicKey,
+import { getLastNImages } from "./shared/file-storage/image-history";
-  GooglePalmKey,
+import { keyPool } from "./shared/key-management";
-  OpenAIKey,
+import { MODEL_FAMILY_SERVICE, ModelFamily } from "./shared/models";
-  keyPool,
+import { withSession } from "./shared/with-session";
-} from "./shared/key-management";
+import { checkCsrfToken, injectCsrfToken } from "./shared/inject-csrf";
-import { ModelFamily, OpenAIModelFamily } from "./shared/models";
-import { getUniqueIps } from "./proxy/rate-limit";
-import { getEstimatedWaitTime, getQueueLength } from "./proxy/queue";
-import { getTokenCostUsd, prettyTokens } from "./shared/stats";
-import { assertNever } from "./shared/utils";
 
 const INFO_PAGE_TTL = 2000;
+const MODEL_FAMILY_FRIENDLY_NAME: { [f in ModelFamily]: string } = {
+  turbo: "GPT-3.5 Turbo",
+  gpt4: "GPT-4",
+  "gpt4-32k": "GPT-4 32k",
+  "gpt4-turbo": "GPT-4 Turbo",
+  "dall-e": "DALL-E",
+  claude: "Claude (Sonnet)",
+  "claude-opus": "Claude (Opus)",
+  "gemini-pro": "Gemini Pro",
+  "mistral-tiny": "Mistral 7B",
+  "mistral-small": "Mixtral Small", // Originally 8x7B, but that now refers to the older open-weight version. Mixtral Small is a newer closed-weight update to the 8x7B model.
+  "mistral-medium": "Mistral Medium",
+  "mistral-large": "Mistral Large",
+  "aws-claude": "AWS Claude (Sonnet)",
+  "azure-turbo": "Azure GPT-3.5 Turbo",
+  "azure-gpt4": "Azure GPT-4",
+  "azure-gpt4-32k": "Azure GPT-4 32k",
+  "azure-gpt4-turbo": "Azure GPT-4 Turbo",
+  "azure-dall-e": "Azure DALL-E",
+};
+
+const converter = new showdown.Converter();
+const customGreeting = fs.existsSync("greeting.md")
+  ? `\n## Server Greeting\n${fs.readFileSync("greeting.md", "utf8")}`
+  : "";
 let infoPageHtml: string | undefined;
 let infoPageLastUpdated = 0;
 
-type KeyPoolKey = ReturnType<typeof keyPool.list>[0];
-const keyIsOpenAIKey = (k: KeyPoolKey): k is OpenAIKey =>
-  k.service === "openai";
-const keyIsAnthropicKey = (k: KeyPoolKey): k is AnthropicKey =>
-  k.service === "anthropic";
-const keyIsGooglePalmKey = (k: KeyPoolKey): k is GooglePalmKey =>
-  k.service === "google-palm";
-
-type ModelAggregates = {
-  active: number;
-  trial?: number;
-  revoked?: number;
-  overQuota?: number;
-  pozzed?: number;
-  queued: number;
-  queueTime: string;
-  tokens: number;
-};
-type ModelAggregateKey = `${ModelFamily}__${keyof ModelAggregates}`;
-type ServiceAggregates = {
-  status?: string;
-  openaiKeys?: number;
-  openaiOrgs?: number;
-  anthropicKeys?: number;
-  palmKeys?: number;
-  proompts: number;
-  tokens: number;
-  tokenCost: number;
-  openAiUncheckedKeys?: number;
-  anthropicUncheckedKeys?: number;
-} & {
-  [modelFamily in ModelFamily]?: ModelAggregates;
-};
-
-const modelStats = new Map<ModelAggregateKey, number>();
-const serviceStats = new Map<keyof ServiceAggregates, number>();
-
 export const handleInfoPage = (req: Request, res: Response) => {
   if (infoPageLastUpdated + INFO_PAGE_TTL > Date.now()) {
-    res.send(infoPageHtml);
+    return res.send(infoPageHtml);
-    return;
   }
 
-  // Sometimes huggingface doesn't send the host header and makes us guess.
   const baseUrl =
     process.env.SPACE_ID && !req.get("host")?.includes("hf.space")
       ? getExternalUrlForHuggingfaceSpaceId(process.env.SPACE_ID)
       : req.protocol + "://" + req.get("host");
 
-  res.send(cacheInfoPageHtml(baseUrl));
+  const info = buildInfo(baseUrl + config.proxyEndpointRoute);
+  infoPageHtml = renderPage(info);
+  infoPageLastUpdated = Date.now();
+
+  res.send(infoPageHtml);
 };
 
-function getCostString(cost: number) {
+export function renderPage(info: ServiceInfo) {
-  if (!config.showTokenCosts) return "";
-  return ` ($${cost.toFixed(2)})`;
-}
-
-function cacheInfoPageHtml(baseUrl: string) {
-  const keys = keyPool.list();
-
-  modelStats.clear();
-  serviceStats.clear();
-  keys.forEach(addKeyToAggregates);
-
-  const openaiKeys = serviceStats.get("openaiKeys") || 0;
-  const anthropicKeys = serviceStats.get("anthropicKeys") || 0;
-  const palmKeys = serviceStats.get("palmKeys") || 0;
-  const proompts = serviceStats.get("proompts") || 0;
-  const tokens = serviceStats.get("tokens") || 0;
-  const tokenCost = serviceStats.get("tokenCost") || 0;
-
-  const info = {
-    uptime: Math.floor(process.uptime()),
-    endpoints: {
-      ...(openaiKeys ? { openai: baseUrl + "/proxy/openai" } : {}),
-      ...(openaiKeys
-        ? { ["openai2"]: baseUrl + "/proxy/openai/turbo-instruct" }
-        : {}),
-      ...(anthropicKeys ? { anthropic: baseUrl + "/proxy/anthropic" } : {}),
-      ...(palmKeys ? { "google-palm": baseUrl + "/proxy/google-palm" } : {}),
-    },
-    proompts,
-    tookens: `${prettyTokens(tokens)}${getCostString(tokenCost)}`,
-    ...(config.modelRateLimit ? { proomptersNow: getUniqueIps() } : {}),
-    openaiKeys,
-    anthropicKeys,
-    palmKeys,
-    ...(openaiKeys ? getOpenAIInfo() : {}),
-    ...(anthropicKeys ? getAnthropicInfo() : {}),
-    ...(palmKeys ? { "palm-bison": getPalmInfo() } : {}),
-    config: listConfig(),
-    build: process.env.BUILD_INFO || "dev",
-  };
-
   const title = getServerTitle();
-  const headerHtml = buildInfoPageHeader(new showdown.Converter(), title);
+  const headerHtml = buildInfoPageHeader(info);
 
-  const pageBody = `<!DOCTYPE html>
+  return `<!DOCTYPE html>
 <html lang="en">
   <head>
     <meta charset="utf-8" />
     <meta name="robots" content="noindex" />
     <title>${title}</title>
+    <style>
+      body {
+        font-family: sans-serif;
+        background-color: #f0f0f0;
+        padding: 1em;
+      }
+      @media (prefers-color-scheme: dark) {
+        body {
+          background-color: #222;
+          color: #eee;
+        }
+        
+        a:link, a:visited {
+          color: #bbe;
+        }
+      }
+    </style>
   </head>
-  <body style="font-family: sans-serif; background-color: #f0f0f0; padding: 1em;">
+  <body>
     ${headerHtml}
     <hr />
     <h2>Service Info</h2>
@@ -130,270 +92,52 @@ function cacheInfoPageHtml(baseUrl: string) {
     ${getSelfServiceLinks()}
   </body>
 </html>`;
-
-  infoPageHtml = pageBody;
-  infoPageLastUpdated = Date.now();
-
-  return pageBody;
 }
 
-function getUniqueOpenAIOrgs(keys: KeyPoolKey[]) {
-  const orgIds = new Set(
-    keys.filter((k) => k.service === "openai").map((k: any) => k.organizationId)
-  );
-  return orgIds.size;
-}
-
-function increment<T extends keyof ServiceAggregates | ModelAggregateKey>(
-  map: Map<T, number>,
-  key: T,
-  delta = 1
-) {
-  map.set(key, (map.get(key) || 0) + delta);
-}
-
-function addKeyToAggregates(k: KeyPoolKey) {
-  increment(serviceStats, "proompts", k.promptCount);
-  increment(serviceStats, "openaiKeys", k.service === "openai" ? 1 : 0);
-  increment(serviceStats, "anthropicKeys", k.service === "anthropic" ? 1 : 0);
-  increment(serviceStats, "palmKeys", k.service === "google-palm" ? 1 : 0);
-
-  let sumTokens = 0;
-  let sumCost = 0;
-  let family: ModelFamily;
-  const families = k.modelFamilies.filter((f) =>
-    config.allowedModelFamilies.includes(f)
-  );
-
-  switch (k.service) {
-    case "openai":
-    case "openai-text":
-      if (!keyIsOpenAIKey(k)) throw new Error("Invalid key type");
-      increment(
-        serviceStats,
-        "openAiUncheckedKeys",
-        Boolean(k.lastChecked) ? 0 : 1
-      );
-
-      // Technically this would not account for keys that have tokens recorded
-      // on models they aren't provisioned for, but that would be strange
-      k.modelFamilies.forEach((f) => {
-        const tokens = k[`${f}Tokens`];
-        sumTokens += tokens;
-        sumCost += getTokenCostUsd(f, tokens);
-        increment(modelStats, `${f}__tokens`, tokens);
-      });
-
-      if (families.includes("gpt4-32k")) {
-        family = "gpt4-32k";
-      } else if (families.includes("gpt4")) {
-        family = "gpt4";
-      } else {
-        family = "turbo";
-      }
-      break;
-    case "anthropic":
-      if (!keyIsAnthropicKey(k)) throw new Error("Invalid key type");
-      family = "claude";
-      sumTokens += k.claudeTokens;
-      sumCost += getTokenCostUsd(family, k.claudeTokens);
-      increment(modelStats, `${family}__tokens`, k.claudeTokens);
-      increment(modelStats, `${family}__pozzed`, k.isPozzed ? 1 : 0);
-      increment(
-        serviceStats,
-        "anthropicUncheckedKeys",
-        Boolean(k.lastChecked) ? 0 : 1
-      );
-      break;
-    case "google-palm":
-      if (!keyIsGooglePalmKey(k)) throw new Error("Invalid key type");
-      family = "bison";
-      sumTokens += k.bisonTokens;
-      sumCost += getTokenCostUsd(family, k.bisonTokens);
-      increment(modelStats, `${family}__tokens`, k.bisonTokens);
-      break;
-    default:
-      assertNever(k.service);
-  }
-
-  increment(serviceStats, "tokens", sumTokens);
-  increment(serviceStats, "tokenCost", sumCost);
-  increment(modelStats, `${family}__active`, k.isDisabled ? 0 : 1);
-  increment(modelStats, `${family}__trial`, k.isTrial ? 1 : 0);
-  if ("isRevoked" in k) {
-    increment(modelStats, `${family}__revoked`, k.isRevoked ? 1 : 0);
-  }
-  if ("isOverQuota" in k) {
-    increment(modelStats, `${family}__overQuota`, k.isOverQuota ? 1 : 0);
-  }
-}
-
-function getOpenAIInfo() {
-  const info: { status?: string; openaiKeys?: number; openaiOrgs?: number } & {
-    [modelFamily in OpenAIModelFamily]?: {
-      usage?: string;
-      activeKeys: number;
-      trialKeys?: number;
-      revokedKeys?: number;
-      overQuotaKeys?: number;
-      proomptersInQueue?: number;
-      estimatedQueueTime?: string;
-    };
-  } = {};
-
-  const allowedFamilies = new Set(config.allowedModelFamilies);
-  let families = new Set<OpenAIModelFamily>();
-  const keys = keyPool.list().filter((k) => {
-    const isOpenAI = keyIsOpenAIKey(k);
-    if (isOpenAI) k.modelFamilies.forEach((f) => families.add(f));
-    return isOpenAI;
-  }) as Omit<OpenAIKey, "key">[];
-  families = new Set([...families].filter((f) => allowedFamilies.has(f)));
-
-  if (config.checkKeys) {
-    const unchecked = serviceStats.get("openAiUncheckedKeys") || 0;
-    if (unchecked > 0) {
-      info.status = `Checking ${unchecked} keys...`;
-    }
-    info.openaiKeys = keys.length;
-    info.openaiOrgs = getUniqueOpenAIOrgs(keys);
-
-    families.forEach((f) => {
-      const tokens = modelStats.get(`${f}__tokens`) || 0;
-      const cost = getTokenCostUsd(f, tokens);
-
-      info[f] = {
-        usage: `${prettyTokens(tokens)} tokens${getCostString(cost)}`,
-        activeKeys: modelStats.get(`${f}__active`) || 0,
-        trialKeys: modelStats.get(`${f}__trial`) || 0,
-        revokedKeys: modelStats.get(`${f}__revoked`) || 0,
-        overQuotaKeys: modelStats.get(`${f}__overQuota`) || 0,
-      };
-    });
-  } else {
-    info.status = "Key checking is disabled.";
-    info.turbo = { activeKeys: keys.filter((k) => !k.isDisabled).length };
-    info.gpt4 = {
-      activeKeys: keys.filter(
-        (k) => !k.isDisabled && k.modelFamilies.includes("gpt4")
-      ).length,
-    };
-  }
-
-  families.forEach((f) => {
-    if (info[f]) {
-      const { estimatedQueueTime, proomptersInQueue } = getQueueInformation(f);
-      info[f]!.proomptersInQueue = proomptersInQueue;
-      info[f]!.estimatedQueueTime = estimatedQueueTime;
-    }
-  });
-
-  return info;
-}
-
-function getAnthropicInfo() {
-  const claudeInfo: Partial<ModelAggregates> = {
-    active: modelStats.get("claude__active") || 0,
-    pozzed: modelStats.get("claude__pozzed") || 0,
-  };
-
-  const queue = getQueueInformation("claude");
-  claudeInfo.queued = queue.proomptersInQueue;
-  claudeInfo.queueTime = queue.estimatedQueueTime;
-
-  const tokens = modelStats.get("claude__tokens") || 0;
-  const cost = getTokenCostUsd("claude", tokens);
-
-  const unchecked =
-    (config.checkKeys && serviceStats.get("anthropicUncheckedKeys")) || 0;
-
-  return {
-    claude: {
-      usage: `${prettyTokens(tokens)} tokens${getCostString(cost)}`,
-      ...(unchecked > 0 ? { status: `Checking ${unchecked} keys...` } : {}),
-      activeKeys: claudeInfo.active,
-      ...(config.checkKeys ? { pozzedKeys: claudeInfo.pozzed } : {}),
-      proomptersInQueue: claudeInfo.queued,
-      estimatedQueueTime: claudeInfo.queueTime,
-    },
-  };
-}
-
-function getPalmInfo() {
-  const bisonInfo: Partial<ModelAggregates> = {
-    active: modelStats.get("bison__active") || 0,
-  };
-
-  const queue = getQueueInformation("bison");
-  bisonInfo.queued = queue.proomptersInQueue;
-  bisonInfo.queueTime = queue.estimatedQueueTime;
-
-  const tokens = modelStats.get("bison__tokens") || 0;
-  const cost = getTokenCostUsd("bison", tokens);
-
-  return {
-    usage: `${prettyTokens(tokens)} tokens${getCostString(cost)}`,
-    activeKeys: bisonInfo.active,
-    proomptersInQueue: bisonInfo.queued,
-    estimatedQueueTime: bisonInfo.queueTime,
-  };
-}
-
-const customGreeting = fs.existsSync("greeting.md")
-  ? fs.readFileSync("greeting.md", "utf8")
-  : null;
-
 /**
  * If the server operator provides a `greeting.md` file, it will be included in
  * the rendered info page.
  **/
-function buildInfoPageHeader(converter: showdown.Converter, title: string) {
+function buildInfoPageHeader(info: ServiceInfo) {
+  const title = getServerTitle();
   // TODO: use some templating engine instead of this mess
-  let infoBody = `<!-- Header for Showdown's parser, don't remove this line -->
+  let infoBody = `# ${title}`;
-# ${title}`;
   if (config.promptLogging) {
-    infoBody += `\n## Prompt logging is enabled!
+    infoBody += `\n## Prompt Logging Enabled
-The server operator has enabled prompt logging. The prompts you send to this proxy and the AI responses you receive may be saved.
+This proxy keeps full logs of all prompts and AI responses. Prompt logs are anonymous and do not contain IP addresses or timestamps.
 
-Logs are anonymous and do not contain IP addresses or timestamps. [You can see the type of data logged here, along with the rest of the code.](https://gitgud.io/khanon/oai-reverse-proxy/-/blob/main/src/prompt-logging/index.ts).
+[You can see the type of data logged here, along with the rest of the code.](https://gitgud.io/khanon/oai-reverse-proxy/-/blob/main/src/shared/prompt-logging/index.ts).
 
 **If you are uncomfortable with this, don't send prompts to this proxy!**`;
   }
 
+  if (config.staticServiceInfo) {
+    return converter.makeHtml(infoBody + customGreeting);
+  }
+
   const waits: string[] = [];
-  infoBody += `\n## Estimated Wait Times\nIf the AI is busy, your prompt will processed when a slot frees up.`;
 
-  if (config.openaiKey) {
+  for (const modelFamily of config.allowedModelFamilies) {
-    // TODO: un-fuck this
+    const service = MODEL_FAMILY_SERVICE[modelFamily];
-    const keys = keyPool.list().filter((k) => k.service === "openai");
 
-    const turboWait = getQueueInformation("turbo").estimatedQueueTime;
+    const hasKeys = keyPool.list().some((k) => {
-    waits.push(`**Turbo:** ${turboWait}`);
+      return k.service === service && k.modelFamilies.includes(modelFamily);
+    });
 
-    const gpt4Wait = getQueueInformation("gpt4").estimatedQueueTime;
+    const wait = info[modelFamily]?.estimatedQueueTime;
-    const hasGpt4 = keys.some((k) => k.modelFamilies.includes("gpt4"));
+    if (hasKeys && wait) {
-    const allowedGpt4 = config.allowedModelFamilies.includes("gpt4");
+      waits.push(
-    if (hasGpt4 && allowedGpt4) {
+        `**${MODEL_FAMILY_FRIENDLY_NAME[modelFamily] || modelFamily}**: ${wait}`
-      waits.push(`**GPT-4:** ${gpt4Wait}`);
+      );
-    }
-
-    const gpt432kWait = getQueueInformation("gpt4-32k").estimatedQueueTime;
-    const hasGpt432k = keys.some((k) => k.modelFamilies.includes("gpt4-32k"));
-    const allowedGpt432k = config.allowedModelFamilies.includes("gpt4-32k");
-    if (hasGpt432k && allowedGpt432k) {
-      waits.push(`**GPT-4-32k:** ${gpt432kWait}`);
     }
   }
 
-  if (config.anthropicKey) {
-    const claudeWait = getQueueInformation("claude").estimatedQueueTime;
-    waits.push(`**Claude:** ${claudeWait}`);
-  }
   infoBody += "\n\n" + waits.join(" / ");
 
-  if (customGreeting) {
+  infoBody += customGreeting;
-    infoBody += `\n## Server Greeting\n${customGreeting}`;
+
-  }
+  infoBody += buildRecentImageSection();
+
   return converter.makeHtml(infoBody);
 }
 
@@ -402,21 +146,6 @@ function getSelfServiceLinks() {
   return `<footer style="font-size: 0.8em;"><hr /><a target="_blank" href="/user/lookup">Check your user token info</a></footer>`;
 }
 
-/** Returns queue time in seconds, or minutes + seconds if over 60 seconds. */
-function getQueueInformation(partition: ModelFamily) {
-  const waitMs = getEstimatedWaitTime(partition);
-  const waitTime =
-    waitMs < 60000
-      ? `${Math.round(waitMs / 1000)}sec`
-      : `${Math.round(waitMs / 60000)}min, ${Math.round(
-          (waitMs % 60000) / 1000
-        )}sec`;
-  return {
-    proomptersInQueue: getQueueLength(partition),
-    estimatedQueueTime: waitMs > 2000 ? waitTime : "no wait",
-  };
-}
-
 function getServerTitle() {
   // Use manually set title if available
   if (process.env.SERVER_TITLE) {
@@ -436,9 +165,46 @@ function getServerTitle() {
   return "OAI Reverse Proxy";
 }
 
+function buildRecentImageSection() {
+  const dalleModels: ModelFamily[] = ["azure-dall-e", "dall-e"];
+  if (
+    !config.showRecentImages ||
+    dalleModels.every((f) => !config.allowedModelFamilies.includes(f))
+  ) {
+    return "";
+  }
+
+  let html = `<h2>Recent DALL-E Generations</h2>`;
+  const recentImages = getLastNImages(12).reverse();
+  if (recentImages.length === 0) {
+    html += `<p>No images yet.</p>`;
+    return html;
+  }
+
+  html += `<div style="display: flex; flex-wrap: wrap;" id="recent-images">`;
+  for (const { url, prompt } of recentImages) {
+    const thumbUrl = url.replace(/\.png$/, "_t.jpg");
+    const escapedPrompt = escapeHtml(prompt);
+    html += `<div style="margin: 0.5em;" class="recent-image">
+<a href="${url}" target="_blank"><img src="${thumbUrl}" title="${escapedPrompt}" alt="${escapedPrompt}" style="max-width: 150px; max-height: 150px;" /></a>
+</div>`;
+  }
+  html += `</div>`;
+  html += `<p style="clear: both; text-align: center;"><a href="/user/image-history">View all recent images</a></p>`
+
+  return html;
+}
+
+function escapeHtml(unsafe: string) {
+  return unsafe
+    .replace(/&/g, "&amp;")
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;")
+    .replace(/"/g, "&quot;")
+    .replace(/'/g, "&#39;");
+}
+
 function getExternalUrlForHuggingfaceSpaceId(spaceId: string) {
-  // Huggingface broke their amazon elb config and no longer sends the
-  // x-forwarded-host header. This is a workaround.
   try {
     const [username, spacename] = spaceId.split("/");
     return `https://${username}-${spacename.replace(/_/g, "-")}.hf.space`;
@@ -446,3 +212,49 @@ function getExternalUrlForHuggingfaceSpaceId(spaceId: string) {
     return "";
   }
 }
+
+function checkIfUnlocked(
+  req: Request,
+  res: Response,
+  next: express.NextFunction
+) {
+  if (config.serviceInfoPassword?.length && !req.session?.unlocked) {
+    return res.redirect("/unlock-info");
+  }
+  next();
+}
+
+const infoPageRouter = Router();
+if (config.serviceInfoPassword?.length) {
+  infoPageRouter.use(
+    express.json({ limit: "1mb" }),
+    express.urlencoded({ extended: true, limit: "1mb" })
+  );
+  infoPageRouter.use(withSession);
+  infoPageRouter.use(injectCsrfToken, checkCsrfToken);
+  infoPageRouter.post("/unlock-info", (req, res) => {
+    if (req.body.password !== config.serviceInfoPassword) {
+      return res.status(403).send("Incorrect password");
+    }
+    req.session!.unlocked = true;
+    res.redirect("/");
+  });
+  infoPageRouter.get("/unlock-info", (_req, res) => {
+    if (_req.session?.unlocked) return res.redirect("/");
+
+    res.send(`
+      <form method="post" action="/unlock-info">
+        <h1>Unlock Service Info</h1>
+        <input type="hidden" name="_csrf" value="${res.locals.csrfToken}" />
+        <input type="password" name="password" placeholder="Password" />
+        <button type="submit">Unlock</button>
+      </form>
+    `);
+  });
+  infoPageRouter.use(checkIfUnlocked);
+}
+infoPageRouter.get("/", handleInfoPage);
+infoPageRouter.get("/status", (req, res) => {
+  res.json(buildInfo(req.protocol + "://" + req.get("host"), false));
+});
+export { infoPageRouter };

src/logger.ts

@@ -1,6 +1,20 @@
 import pino from "pino";
 import { config } from "./config";
 
+const transport =
+  process.env.NODE_ENV === "production"
+    ? undefined
+    : {
+        target: "pino-pretty",
+        options: {
+          singleLine: true,
+          messageFormat: "{if module}\x1b[90m[{module}] \x1b[39m{end}{msg}",
+          ignore: "module",
+        },
+      };
+
 export const logger = pino({
   level: config.logLevel,
+  base: { pid: process.pid, module: "server" },
+  transport,
 });

src/proxy/anthropic.ts

@@ -1,5 +1,4 @@
-import { Request, RequestHandler, Router } from "express";
+import { Request, Response, RequestHandler, Router } from "express";
-import * as http from "http";
 import { createProxyMiddleware } from "http-proxy-middleware";
 import { config } from "../config";
 import { logger } from "../logger";
@@ -8,18 +7,16 @@ import { ipLimiter } from "./rate-limit";
 import { handleProxyError } from "./middleware/common";
 import {
   addKey,
-  applyQuotaLimits,
   addAnthropicPreamble,
-  blockZoomerOrigins,
   createPreprocessorMiddleware,
   finalizeBody,
-  languageFilter,
+  createOnProxyReqHandler,
-  removeOriginHeaders,
 } from "./middleware/request";
 import {
   ProxyResHandlerWithBody,
   createOnProxyResHandler,
 } from "./middleware/response";
+import { sendErrorToClient } from "./middleware/response/error-generator";
 
 let modelsCache: any = null;
 let modelsCacheTime = 0;
@@ -43,8 +40,12 @@ const getModelsResponse = () => {
     "claude-instant-v1.1",
     "claude-instant-v1.1-100k",
     "claude-instant-v1.0",
-    "claude-2", // claude-2 is 100k by default it seems
+    "claude-2",
     "claude-2.0",
+    "claude-2.1",
+    "claude-3-haiku-20240307",
+    "claude-3-opus-20240229",
+    "claude-3-sonnet-20240229",
   ];
 
   const models = claudeVariants.map((id) => ({
@@ -67,31 +68,6 @@ const handleModelRequest: RequestHandler = (_req, res) => {
   res.status(200).json(getModelsResponse());
 };
 
-const rewriteAnthropicRequest = (
-  proxyReq: http.ClientRequest,
-  req: Request,
-  res: http.ServerResponse
-) => {
-  const rewriterPipeline = [
-    applyQuotaLimits,
-    addKey,
-    addAnthropicPreamble,
-    languageFilter,
-    blockZoomerOrigins,
-    removeOriginHeaders,
-    finalizeBody,
-  ];
-
-  try {
-    for (const rewriter of rewriterPipeline) {
-      rewriter(proxyReq, req, res, {});
-    }
-  } catch (error) {
-    req.log.error(error, "Error while executing proxy rewriter");
-    proxyReq.destroy(error as Error);
-  }
-};
-
 /** Only used for non-streaming requests. */
 const anthropicResponseHandler: ProxyResHandlerWithBody = async (
   _proxyRes,
@@ -103,31 +79,56 @@ const anthropicResponseHandler: ProxyResHandlerWithBody = async (
     throw new Error("Expected body to be an object");
   }
 
-  if (config.promptLogging) {
+  let newBody = body;
-    const host = req.get("host");
+  switch (`${req.inboundApi}<-${req.outboundApi}`) {
-    body.proxy_note = `Prompts are logged on this proxy instance. See ${host} for more information.`;
+    case "openai<-anthropic-text":
+      req.log.info("Transforming Anthropic Text back to OpenAI format");
+      newBody = transformAnthropicTextResponseToOpenAI(body, req);
+      break;
+    case "openai<-anthropic-chat":
+      req.log.info("Transforming Anthropic Chat back to OpenAI format");
+      newBody = transformAnthropicChatResponseToOpenAI(body);
+      break;
+    case "anthropic-text<-anthropic-chat":
+      req.log.info("Transforming Anthropic Chat back to Anthropic chat format");
+      newBody = transformAnthropicChatResponseToAnthropicText(body);
+      break;
   }
 
-  if (req.inboundApi === "openai") {
+  res.status(200).json({ ...newBody, proxy: body.proxy });
-    req.log.info("Transforming Anthropic response to OpenAI format");
-    body = transformAnthropicResponse(body, req);
-  }
-
-  // TODO: Remove once tokenization is stable
-  if (req.debug) {
-    body.proxy_tokenizer_debug_info = req.debug;
-  }
-
-  res.status(200).json(body);
 };
 
+function flattenChatResponse(
+  content: { type: string; text: string }[]
+): string {
+  return content
+    .map((part: { type: string; text: string }) =>
+      part.type === "text" ? part.text : ""
+    )
+    .join("\n");
+}
+
+export function transformAnthropicChatResponseToAnthropicText(
+  anthropicBody: Record<string, any>
+): Record<string, any> {
+  return {
+    type: "completion",
+    id: "ant-" + anthropicBody.id,
+    completion: flattenChatResponse(anthropicBody.content),
+    stop_reason: anthropicBody.stop_reason,
+    stop: anthropicBody.stop_sequence,
+    model: anthropicBody.model,
+    usage: anthropicBody.usage,
+  };
+}
+
 /**
  * Transforms a model response from the Anthropic API to match those from the
  * OpenAI API, for users using Claude via the OpenAI-compatible endpoint. This
  * is only used for non-streaming requests as streaming requests are handled
  * on-the-fly.
  */
-function transformAnthropicResponse(
+function transformAnthropicTextResponseToOpenAI(
   anthropicBody: Record<string, any>,
   req: Request
 ): Record<string, any> {
@@ -155,54 +156,200 @@ function transformAnthropicResponse(
   };
 }
 
-const anthropicProxy = createQueueMiddleware(
+function transformAnthropicChatResponseToOpenAI(
-  createProxyMiddleware({
+  anthropicBody: Record<string, any>
+): Record<string, any> {
+  return {
+    id: "ant-" + anthropicBody.id,
+    object: "chat.completion",
+    created: Date.now(),
+    model: anthropicBody.model,
+    usage: anthropicBody.usage,
+    choices: [
+      {
+        message: {
+          role: "assistant",
+          content: flattenChatResponse(anthropicBody.content),
+        },
+        finish_reason: anthropicBody.stop_reason,
+        index: 0,
+      },
+    ],
+  };
+}
+
+const anthropicProxy = createQueueMiddleware({
+  proxyMiddleware: createProxyMiddleware({
     target: "https://api.anthropic.com",
     changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
     on: {
-      proxyReq: rewriteAnthropicRequest,
+      proxyReq: createOnProxyReqHandler({
+        pipeline: [addKey, addAnthropicPreamble, finalizeBody],
+      }),
       proxyRes: createOnProxyResHandler([anthropicResponseHandler]),
       error: handleProxyError,
     },
-    selfHandleResponse: true,
+    // Abusing pathFilter to rewrite the paths dynamically.
-    logger,
+    pathFilter: (pathname, req) => {
-    pathRewrite: {
+      const isText = req.outboundApi === "anthropic-text";
-      // Send OpenAI-compat requests to the real Anthropic endpoint.
+      const isChat = req.outboundApi === "anthropic-chat";
-      "^/v1/chat/completions": "/v1/complete",
+      if (isChat && pathname === "/v1/complete") {
+        req.url = "/v1/messages";
+      }
+      if (isText && pathname === "/v1/chat/completions") {
+        req.url = "/v1/complete";
+      }
+      if (isChat && pathname === "/v1/chat/completions") {
+        req.url = "/v1/messages";
+      }
+      if (isChat && ["sonnet", "opus"].includes(req.params.type)) {
+        req.url = "/v1/messages";
+      }
+      return true;
     },
-  })
+  }),
-);
+});
+
+const nativeTextPreprocessor = createPreprocessorMiddleware({
+  inApi: "anthropic-text",
+  outApi: "anthropic-text",
+  service: "anthropic",
+});
+
+const textToChatPreprocessor = createPreprocessorMiddleware({
+  inApi: "anthropic-text",
+  outApi: "anthropic-chat",
+  service: "anthropic",
+});
+
+/**
+ * Routes text completion prompts to anthropic-chat if they need translation
+ * (claude-3 based models do not support the old text completion endpoint).
+ */
+const preprocessAnthropicTextRequest: RequestHandler = (req, res, next) => {
+  if (req.body.model?.startsWith("claude-3")) {
+    textToChatPreprocessor(req, res, next);
+  } else {
+    nativeTextPreprocessor(req, res, next);
+  }
+};
+
+const oaiToTextPreprocessor = createPreprocessorMiddleware({
+  inApi: "openai",
+  outApi: "anthropic-text",
+  service: "anthropic",
+});
+
+const oaiToChatPreprocessor = createPreprocessorMiddleware({
+  inApi: "openai",
+  outApi: "anthropic-chat",
+  service: "anthropic",
+});
+
+/**
+ * Routes an OpenAI prompt to either the legacy Claude text completion endpoint
+ * or the new Claude chat completion endpoint, based on the requested model.
+ */
+const preprocessOpenAICompatRequest: RequestHandler = (req, res, next) => {
+  maybeReassignModel(req);
+  if (req.body.model?.includes("claude-3")) {
+    oaiToChatPreprocessor(req, res, next);
+  } else {
+    oaiToTextPreprocessor(req, res, next);
+  }
+};
 
 const anthropicRouter = Router();
-// Fix paths because clients don't consistently use the /v1 prefix.
-anthropicRouter.use((req, _res, next) => {
-  if (!req.path.startsWith("/v1/")) {
-    req.url = `/v1${req.url}`;
-  }
-  next();
-});
 anthropicRouter.get("/v1/models", handleModelRequest);
+// Native Anthropic chat completion endpoint.
+anthropicRouter.post(
+  "/v1/messages",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "anthropic-chat",
+    outApi: "anthropic-chat",
+    service: "anthropic",
+  }),
+  anthropicProxy
+);
+// Anthropic text completion endpoint. Translates to Anthropic chat completion
+// if the requested model is a Claude 3 model.
 anthropicRouter.post(
   "/v1/complete",
   ipLimiter,
-  createPreprocessorMiddleware({ inApi: "anthropic", outApi: "anthropic" }),
+  preprocessAnthropicTextRequest,
   anthropicProxy
 );
-// OpenAI-to-Anthropic compatibility endpoint.
+// OpenAI-to-Anthropic compatibility endpoint. Accepts an OpenAI chat completion
+// request and transforms/routes it to the appropriate Anthropic format and
+// endpoint based on the requested model.
 anthropicRouter.post(
   "/v1/chat/completions",
   ipLimiter,
-  createPreprocessorMiddleware({ inApi: "openai", outApi: "anthropic" }),
+  preprocessOpenAICompatRequest,
   anthropicProxy
 );
-// Redirect browser requests to the homepage.
+// Temporarily force Anthropic Text to Anthropic Chat for frontends which do not
-anthropicRouter.get("*", (req, res, next) => {
+// yet support the new model. Forces claude-3. Will be removed once common
-  const isBrowser = req.headers["user-agent"]?.includes("Mozilla");
+// frontends have been updated.
-  if (isBrowser) {
+anthropicRouter.post(
-    res.redirect("/");
+  "/v1/:type(sonnet|opus)/:action(complete|messages)",
-  } else {
+  ipLimiter,
-    next();
+  handleAnthropicTextCompatRequest,
+  createPreprocessorMiddleware({
+    inApi: "anthropic-text",
+    outApi: "anthropic-chat",
+    service: "anthropic",
+  }),
+  anthropicProxy
+);
+
+function handleAnthropicTextCompatRequest(
+  req: Request,
+  res: Response,
+  next: any
+) {
+  const type = req.params.type;
+  const action = req.params.action;
+  const alreadyInChatFormat = Boolean(req.body.messages);
+  const compatModel = `claude-3-${type}-20240229`;
+  req.log.info(
+    { type, inputModel: req.body.model, compatModel, alreadyInChatFormat },
+    "Handling Anthropic compatibility request"
+  );
+
+  if (action === "messages" || alreadyInChatFormat) {
+    return sendErrorToClient({
+      req,
+      res,
+      options: {
+        title: "Unnecessary usage of compatibility endpoint",
+        message: `Your client seems to already support the new Claude API format. This endpoint is intended for clients that do not yet support the new format.\nUse the normal \`/anthropic\` proxy endpoint instead.`,
+        format: "unknown",
+        statusCode: 400,
+        reqId: req.id,
+        obj: {
+          requested_endpoint: "/anthropic/" + type,
+          correct_endpoint: "/anthropic",
+        },
+      },
+    });
   }
-});
+
+  req.body.model = compatModel;
+  next();
+}
+
+/**
+ * If a client using the OpenAI compatibility endpoint requests an actual OpenAI
+ * model, reassigns it to Claude 3 Sonnet.
+ */
+function maybeReassignModel(req: Request) {
+  const model = req.body.model;
+  if (!model.startsWith("gpt-")) return;
+  req.body.model = "claude-3-sonnet-20240229";
+}
 
 export const anthropic = anthropicRouter;

src/proxy/aws.ts

@@ -0,0 +1,307 @@
+import { Request, RequestHandler, Response, Router } from "express";
+import { createProxyMiddleware } from "http-proxy-middleware";
+import { v4 } from "uuid";
+import { config } from "../config";
+import { logger } from "../logger";
+import { createQueueMiddleware } from "./queue";
+import { ipLimiter } from "./rate-limit";
+import { handleProxyError } from "./middleware/common";
+import {
+  createPreprocessorMiddleware,
+  signAwsRequest,
+  finalizeSignedRequest,
+  createOnProxyReqHandler,
+} from "./middleware/request";
+import {
+  ProxyResHandlerWithBody,
+  createOnProxyResHandler,
+} from "./middleware/response";
+import { transformAnthropicChatResponseToAnthropicText } from "./anthropic";
+import { sendErrorToClient } from "./middleware/response/error-generator";
+
+const LATEST_AWS_V2_MINOR_VERSION = "1";
+
+let modelsCache: any = null;
+let modelsCacheTime = 0;
+
+const getModelsResponse = () => {
+  if (new Date().getTime() - modelsCacheTime < 1000 * 60) {
+    return modelsCache;
+  }
+
+  if (!config.awsCredentials) return { object: "list", data: [] };
+
+  // https://docs.aws.amazon.com/bedrock/latest/userguide/model-ids.html
+  const variants = [
+    "anthropic.claude-v2",
+    "anthropic.claude-v2:1",
+    "anthropic.claude-3-haiku-20240307-v1:0",
+    "anthropic.claude-3-sonnet-20240229-v1:0",
+  ];
+
+  const models = variants.map((id) => ({
+    id,
+    object: "model",
+    created: new Date().getTime(),
+    owned_by: "anthropic",
+    permission: [],
+    root: "claude",
+    parent: null,
+  }));
+
+  modelsCache = { object: "list", data: models };
+  modelsCacheTime = new Date().getTime();
+
+  return modelsCache;
+};
+
+const handleModelRequest: RequestHandler = (_req, res) => {
+  res.status(200).json(getModelsResponse());
+};
+
+/** Only used for non-streaming requests. */
+const awsResponseHandler: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  res,
+  body
+) => {
+  if (typeof body !== "object") {
+    throw new Error("Expected body to be an object");
+  }
+
+  let newBody = body;
+  switch (`${req.inboundApi}<-${req.outboundApi}`) {
+    case "openai<-anthropic-text":
+      req.log.info("Transforming Anthropic Text back to OpenAI format");
+      newBody = transformAwsTextResponseToOpenAI(body, req);
+      break;
+    // case "openai<-anthropic-chat":
+    // todo: implement this
+    case "anthropic-text<-anthropic-chat":
+      req.log.info("Transforming AWS Anthropic Chat back to Text format");
+      newBody = transformAnthropicChatResponseToAnthropicText(body);
+      break;
+  }
+
+  // AWS does not always confirm the model in the response, so we have to add it
+  if (!newBody.model && req.body.model) {
+    newBody.model = req.body.model;
+  }
+
+  res.status(200).json({ ...newBody, proxy: body.proxy });
+};
+
+/**
+ * Transforms a model response from the Anthropic API to match those from the
+ * OpenAI API, for users using Claude via the OpenAI-compatible endpoint. This
+ * is only used for non-streaming requests as streaming requests are handled
+ * on-the-fly.
+ */
+function transformAwsTextResponseToOpenAI(
+  awsBody: Record<string, any>,
+  req: Request
+): Record<string, any> {
+  const totalTokens = (req.promptTokens ?? 0) + (req.outputTokens ?? 0);
+  return {
+    id: "aws-" + v4(),
+    object: "chat.completion",
+    created: Date.now(),
+    model: req.body.model,
+    usage: {
+      prompt_tokens: req.promptTokens,
+      completion_tokens: req.outputTokens,
+      total_tokens: totalTokens,
+    },
+    choices: [
+      {
+        message: {
+          role: "assistant",
+          content: awsBody.completion?.trim(),
+        },
+        finish_reason: awsBody.stop_reason,
+        index: 0,
+      },
+    ],
+  };
+}
+
+const awsProxy = createQueueMiddleware({
+  beforeProxy: signAwsRequest,
+  proxyMiddleware: createProxyMiddleware({
+    target: "bad-target-will-be-rewritten",
+    router: ({ signedRequest }) => {
+      if (!signedRequest) throw new Error("Must sign request before proxying");
+      return `${signedRequest.protocol}//${signedRequest.hostname}`;
+    },
+    changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
+    on: {
+      proxyReq: createOnProxyReqHandler({ pipeline: [finalizeSignedRequest] }),
+      proxyRes: createOnProxyResHandler([awsResponseHandler]),
+      error: handleProxyError,
+    },
+  }),
+});
+
+const nativeTextPreprocessor = createPreprocessorMiddleware(
+  { inApi: "anthropic-text", outApi: "anthropic-text", service: "aws" },
+  { afterTransform: [maybeReassignModel] }
+);
+
+const textToChatPreprocessor = createPreprocessorMiddleware(
+  { inApi: "anthropic-text", outApi: "anthropic-chat", service: "aws" },
+  { afterTransform: [maybeReassignModel] }
+);
+
+/**
+ * Routes text completion prompts to aws anthropic-chat if they need translation
+ * (claude-3 based models do not support the old text completion endpoint).
+ */
+const awsTextCompletionRouter: RequestHandler = (req, res, next) => {
+  if (req.body.model?.includes("claude-3")) {
+    textToChatPreprocessor(req, res, next);
+  } else {
+    nativeTextPreprocessor(req, res, next);
+  }
+};
+
+const awsRouter = Router();
+awsRouter.get("/v1/models", handleModelRequest);
+// Native(ish) Anthropic text completion endpoint.
+awsRouter.post("/v1/complete", ipLimiter, awsTextCompletionRouter, awsProxy);
+// Native Anthropic chat completion endpoint.
+awsRouter.post(
+  "/v1/messages",
+  ipLimiter,
+  createPreprocessorMiddleware(
+    { inApi: "anthropic-chat", outApi: "anthropic-chat", service: "aws" },
+    { afterTransform: [maybeReassignModel] }
+  ),
+  awsProxy
+);
+// Temporary force-Claude3 endpoint
+awsRouter.post(
+  "/v1/sonnet/:action(complete|messages)",
+  ipLimiter,
+  handleCompatibilityRequest,
+  createPreprocessorMiddleware({
+    inApi: "anthropic-text",
+    outApi: "anthropic-chat",
+    service: "aws",
+  }),
+  awsProxy
+);
+
+// OpenAI-to-AWS Anthropic compatibility endpoint.
+awsRouter.post(
+  "/v1/chat/completions",
+  ipLimiter,
+  createPreprocessorMiddleware(
+    { inApi: "openai", outApi: "anthropic-text", service: "aws" },
+    { afterTransform: [maybeReassignModel] }
+  ),
+  awsProxy
+);
+
+/**
+ * Tries to deal with:
+ * - frontends sending AWS model names even when they want to use the OpenAI-
+ *   compatible endpoint
+ * - frontends sending Anthropic model names that AWS doesn't recognize
+ * - frontends sending OpenAI model names because they expect the proxy to
+ *   translate them
+ */
+function maybeReassignModel(req: Request) {
+  const model = req.body.model;
+
+  // If client already specified an AWS Claude model ID, use it
+  if (model.includes("anthropic.claude")) {
+    return;
+  }
+
+  const pattern =
+    /^(claude-)?(instant-)?(v)?(\d+)(\.(\d+))?(-\d+k)?(-sonnet-?|-opus-?)(\d*)/i;
+  const match = model.match(pattern);
+
+  // If there's no match, return the latest v2 model
+  if (!match) {
+    req.body.model = `anthropic.claude-v2:${LATEST_AWS_V2_MINOR_VERSION}`;
+    return;
+  }
+
+  const instant = match[2];
+  const major = match[4];
+  const minor = match[6];
+
+  if (instant) {
+    req.body.model = "anthropic.claude-instant-v1";
+    return;
+  }
+
+  // There's only one v1 model
+  if (major === "1") {
+    req.body.model = "anthropic.claude-v1";
+    return;
+  }
+
+  // Try to map Anthropic API v2 models to AWS v2 models
+  if (major === "2") {
+    if (minor === "0") {
+      req.body.model = "anthropic.claude-v2";
+      return;
+    }
+    req.body.model = `anthropic.claude-v2:${LATEST_AWS_V2_MINOR_VERSION}`;
+    return;
+  }
+
+  // AWS currently only supports one v3 model.
+  const variant = match[8]; // sonnet or opus
+  const variantVersion = match[9];
+  if (major === "3") {
+    req.body.model = "anthropic.claude-3-sonnet-20240229-v1:0";
+    return;
+  }
+
+  // Fallback to latest v2 model
+  req.body.model = `anthropic.claude-v2:${LATEST_AWS_V2_MINOR_VERSION}`;
+  return;
+}
+
+export function handleCompatibilityRequest(
+  req: Request,
+  res: Response,
+  next: any
+) {
+  const action = req.params.action;
+  const alreadyInChatFormat = Boolean(req.body.messages);
+  const compatModel = "anthropic.claude-3-sonnet-20240229-v1:0";
+  req.log.info(
+    { inputModel: req.body.model, compatModel, alreadyInChatFormat },
+    "Handling AWS compatibility request"
+  );
+
+  if (action === "messages" || alreadyInChatFormat) {
+    return sendErrorToClient({
+      req,
+      res,
+      options: {
+        title: "Unnecessary usage of compatibility endpoint",
+        message: `Your client seems to already support the new Claude API format. This endpoint is intended for clients that do not yet support the new format.\nUse the normal \`/aws/claude\` proxy endpoint instead.`,
+        format: "unknown",
+        statusCode: 400,
+        reqId: req.id,
+        obj: {
+          requested_endpoint: "/aws/claude/sonnet",
+          correct_endpoint: "/aws/claude",
+        },
+      },
+    });
+  }
+
+  req.body.model = compatModel;
+  next();
+}
+
+export const aws = awsRouter;

src/proxy/azure.ts

@@ -0,0 +1,129 @@
+import { RequestHandler, Router } from "express";
+import { createProxyMiddleware } from "http-proxy-middleware";
+import { config } from "../config";
+import { keyPool } from "../shared/key-management";
+import {
+  AzureOpenAIModelFamily,
+  getAzureOpenAIModelFamily,
+  ModelFamily,
+} from "../shared/models";
+import { logger } from "../logger";
+import { KNOWN_OPENAI_MODELS } from "./openai";
+import { createQueueMiddleware } from "./queue";
+import { ipLimiter } from "./rate-limit";
+import { handleProxyError } from "./middleware/common";
+import {
+  addAzureKey,
+  createOnProxyReqHandler,
+  createPreprocessorMiddleware,
+  finalizeSignedRequest,
+} from "./middleware/request";
+import {
+  createOnProxyResHandler,
+  ProxyResHandlerWithBody,
+} from "./middleware/response";
+
+let modelsCache: any = null;
+let modelsCacheTime = 0;
+
+function getModelsResponse() {
+  if (new Date().getTime() - modelsCacheTime < 1000 * 60) {
+    return modelsCache;
+  }
+
+  let available = new Set<AzureOpenAIModelFamily>();
+  for (const key of keyPool.list()) {
+    if (key.isDisabled || key.service !== "azure") continue;
+    key.modelFamilies.forEach((family) =>
+      available.add(family as AzureOpenAIModelFamily)
+    );
+  }
+  const allowed = new Set<ModelFamily>(config.allowedModelFamilies);
+  available = new Set([...available].filter((x) => allowed.has(x)));
+
+  const models = KNOWN_OPENAI_MODELS.map((id) => ({
+    id,
+    object: "model",
+    created: new Date().getTime(),
+    owned_by: "azure",
+    permission: [
+      {
+        id: "modelperm-" + id,
+        object: "model_permission",
+        created: new Date().getTime(),
+        organization: "*",
+        group: null,
+        is_blocking: false,
+      },
+    ],
+    root: id,
+    parent: null,
+  })).filter((model) => available.has(getAzureOpenAIModelFamily(model.id)));
+
+  modelsCache = { object: "list", data: models };
+  modelsCacheTime = new Date().getTime();
+
+  return modelsCache;
+}
+
+const handleModelRequest: RequestHandler = (_req, res) => {
+  res.status(200).json(getModelsResponse());
+};
+
+const azureOpenaiResponseHandler: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  res,
+  body
+) => {
+  if (typeof body !== "object") {
+    throw new Error("Expected body to be an object");
+  }
+
+  res.status(200).json({ ...body, proxy: body.proxy });
+};
+
+const azureOpenAIProxy = createQueueMiddleware({
+  beforeProxy: addAzureKey,
+  proxyMiddleware: createProxyMiddleware({
+    target: "will be set by router",
+    router: (req) => {
+      if (!req.signedRequest) throw new Error("signedRequest not set");
+      const { hostname, path } = req.signedRequest;
+      return `https://${hostname}${path}`;
+    },
+    changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
+    on: {
+      proxyReq: createOnProxyReqHandler({ pipeline: [finalizeSignedRequest] }),
+      proxyRes: createOnProxyResHandler([azureOpenaiResponseHandler]),
+      error: handleProxyError,
+    },
+  }),
+});
+
+const azureOpenAIRouter = Router();
+azureOpenAIRouter.get("/v1/models", handleModelRequest);
+azureOpenAIRouter.post(
+  "/v1/chat/completions",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "openai",
+    outApi: "openai",
+    service: "azure",
+  }),
+  azureOpenAIProxy
+);
+azureOpenAIRouter.post(
+  "/v1/images/generations",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "openai-image",
+    outApi: "openai-image",
+    service: "azure",
+  }),
+  azureOpenAIProxy
+);
+
+export const azure = azureOpenAIRouter;

src/proxy/check-risu-token.ts

@@ -21,7 +21,7 @@ kYuIJbnAGw5Oq0L6dXFW2DFwlcLz51kPVOmDc159FsQjyuPnta7NiZAANS8KM1CJ
 pwIDAQAB`;
 let IMPORTED_RISU_KEY: CryptoKey | null = null;
 
-type RisuToken = { id: Uint8Array; expiresIn: number };
+type RisuToken = { id: string; expiresIn: number };
 type SignedToken = { data: RisuToken; sig: string };
 
 (async () => {
@@ -54,14 +54,14 @@ export async function checkRisuToken(
   try {
     const { valid, data } = await validCheck(header);
 
-    if (!valid) {
+    if (!valid || !data) {
       req.log.warn(
         { token: header, data },
         "Invalid RisuAI token; using IP instead"
       );
     } else {
       req.log.info("RisuAI token validated");
-      req.risuToken = header;
+      req.risuToken = String(data.id);
     }
   } catch (err) {
     req.log.warn(
@@ -81,12 +81,13 @@ async function validCheck(header: string) {
     );
   } catch (err) {
     log.warn({ error: err.message }, "Provided unparseable RisuAI token");
-    return { valid: false, data: "[unparseable]" };
+    return { valid: false };
   }
   const data: RisuToken = tk.data;
   const sig = Buffer.from(tk.sig, "base64");
 
   if (data.expiresIn < Math.floor(Date.now() / 1000)) {
+    log.warn({ token: header }, "Provided expired RisuAI token");
     return { valid: false };
   }
 
@@ -97,5 +98,9 @@ async function validCheck(header: string) {
     Buffer.from(JSON.stringify(data))
   );
 
+  if (!valid) {
+    log.warn({ token: header }, "RisuAI token failed signature check");
+  }
+
   return { valid, data };
 }

src/proxy/gatekeeper.ts

@@ -46,19 +46,30 @@ export const gatekeeper: RequestHandler = (req, res, next) => {
   }
 
   if (GATEKEEPER === "user_token" && token) {
-    const user = authenticate(token, req.ip);
+    // RisuAI users all come from a handful of aws lambda IPs so we cannot use
-    if (user) {
+    // IP alone to distinguish between them and prevent usertoken sharing.
-      req.user = user;
+    // Risu sends a signed token in the request headers with an anonymous user
-      return next();
+    // ID that we can instead use to associate requests with an individual.
-    } else {
+    const ip = req.risuToken?.length ?
-      const maybeBannedUser = getUser(token);
+      `risu${req.risuToken}-${req.ip}` :
-      if (maybeBannedUser?.disabledAt) {
+      req.ip;
+
+    const { user, result } = authenticate(token, ip);
+
+    switch (result) {
+      case "success":
+        req.user = user;
+        return next();
+      case "limited":
         return res.status(403).json({
-          error: `Forbidden: ${
+          error: `Forbidden: no more IPs can authenticate with this token`,
-            maybeBannedUser.disabledReason || "Token disabled"
-          }`,
         });
-      }
+      case "disabled":
+        const bannedUser = getUser(token);
+        if (bannedUser?.disabledAt) {
+          const reason = bannedUser.disabledReason || "Token disabled";
+          return res.status(403).json({ error: `Forbidden: ${reason}` });
+        }
     }
   }
 

src/proxy/google-ai.ts

@@ -0,0 +1,135 @@
+import { Request, RequestHandler, Router } from "express";
+import { createProxyMiddleware } from "http-proxy-middleware";
+import { v4 } from "uuid";
+import { config } from "../config";
+import { logger } from "../logger";
+import { createQueueMiddleware } from "./queue";
+import { ipLimiter } from "./rate-limit";
+import { handleProxyError } from "./middleware/common";
+import {
+  createOnProxyReqHandler,
+  createPreprocessorMiddleware,
+  finalizeSignedRequest,
+} from "./middleware/request";
+import {
+  createOnProxyResHandler,
+  ProxyResHandlerWithBody,
+} from "./middleware/response";
+import { addGoogleAIKey } from "./middleware/request/preprocessors/add-google-ai-key";
+
+let modelsCache: any = null;
+let modelsCacheTime = 0;
+
+// https://ai.google.dev/models/gemini
+// TODO: list models https://ai.google.dev/tutorials/rest_quickstart#list_models
+
+const getModelsResponse = () => {
+  if (new Date().getTime() - modelsCacheTime < 1000 * 60) {
+    return modelsCache;
+  }
+
+  if (!config.googleAIKey) return { object: "list", data: [] };
+
+  const googleAIVariants = ["gemini-pro", "gemini-1.0-pro", "gemini-1.5-pro"];
+
+  const models = googleAIVariants.map((id) => ({
+    id,
+    object: "model",
+    created: new Date().getTime(),
+    owned_by: "google",
+    permission: [],
+    root: "google",
+    parent: null,
+  }));
+
+  modelsCache = { object: "list", data: models };
+  modelsCacheTime = new Date().getTime();
+
+  return modelsCache;
+};
+
+const handleModelRequest: RequestHandler = (_req, res) => {
+  res.status(200).json(getModelsResponse());
+};
+
+/** Only used for non-streaming requests. */
+const googleAIResponseHandler: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  res,
+  body
+) => {
+  if (typeof body !== "object") {
+    throw new Error("Expected body to be an object");
+  }
+
+  let newBody = body;
+  if (req.inboundApi === "openai") {
+    req.log.info("Transforming Google AI response to OpenAI format");
+    newBody = transformGoogleAIResponse(body, req);
+  }
+
+  res.status(200).json({ ...newBody, proxy: body.proxy });
+};
+
+function transformGoogleAIResponse(
+  resBody: Record<string, any>,
+  req: Request
+): Record<string, any> {
+  const totalTokens = (req.promptTokens ?? 0) + (req.outputTokens ?? 0);
+  const parts = resBody.candidates[0].content?.parts ?? [{ text: "" }];
+  const content = parts[0].text.replace(/^(.{0,50}?): /, () => "");
+  return {
+    id: "goo-" + v4(),
+    object: "chat.completion",
+    created: Date.now(),
+    model: req.body.model,
+    usage: {
+      prompt_tokens: req.promptTokens,
+      completion_tokens: req.outputTokens,
+      total_tokens: totalTokens,
+    },
+    choices: [
+      {
+        message: { role: "assistant", content },
+        finish_reason: resBody.candidates[0].finishReason,
+        index: 0,
+      },
+    ],
+  };
+}
+
+const googleAIProxy = createQueueMiddleware({
+  beforeProxy: addGoogleAIKey,
+  proxyMiddleware: createProxyMiddleware({
+    target: "bad-target-will-be-rewritten",
+    router: ({ signedRequest }) => {
+      const { protocol, hostname, path } = signedRequest;
+      return `${protocol}//${hostname}${path}`;
+    },
+    changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
+    on: {
+      proxyReq: createOnProxyReqHandler({ pipeline: [finalizeSignedRequest] }),
+      proxyRes: createOnProxyResHandler([googleAIResponseHandler]),
+      error: handleProxyError,
+    },
+  }),
+});
+
+const googleAIRouter = Router();
+googleAIRouter.get("/v1/models", handleModelRequest);
+// OpenAI-to-Google AI compatibility endpoint.
+googleAIRouter.post(
+  "/v1/chat/completions",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "openai",
+    outApi: "google-ai",
+    service: "google-ai",
+  }),
+  googleAIProxy
+);
+
+export const googleAI = googleAIRouter;

src/proxy/kobold.ts

@@ -1,98 +0,0 @@
-/* Pretends to be a KoboldAI API endpoint and translates incoming Kobold
-requests to OpenAI API equivalents. */
-
-import { Request, Response, Router } from "express";
-import http from "http";
-import { createProxyMiddleware } from "http-proxy-middleware";
-import { config } from "../config";
-import { logger } from "../logger";
-import { ipLimiter } from "./rate-limit";
-import { handleProxyError } from "./middleware/common";
-import {
-  addKey,
-  createPreprocessorMiddleware,
-  finalizeBody,
-  languageFilter,
-  transformKoboldPayload,
-} from "./middleware/request";
-import {
-  createOnProxyResHandler,
-  ProxyResHandlerWithBody,
-} from "./middleware/response";
-
-export const handleModelRequest = (_req: Request, res: Response) => {
-  res.status(200).json({ result: "Connected to OpenAI reverse proxy" });
-};
-
-export const handleSoftPromptsRequest = (_req: Request, res: Response) => {
-  res.status(200).json({ soft_prompts_list: [] });
-};
-
-const rewriteRequest = (
-  proxyReq: http.ClientRequest,
-  req: Request,
-  res: Response
-) => {
-  req.body.stream = false;
-  const rewriterPipeline = [
-    addKey,
-    transformKoboldPayload,
-    languageFilter,
-    finalizeBody,
-  ];
-
-  try {
-    for (const rewriter of rewriterPipeline) {
-      rewriter(proxyReq, req, res, {});
-    }
-  } catch (error) {
-    logger.error(error, "Error while executing proxy rewriter");
-    proxyReq.destroy(error as Error);
-  }
-};
-
-const koboldResponseHandler: ProxyResHandlerWithBody = async (
-  _proxyRes,
-  req,
-  res,
-  body
-) => {
-  if (typeof body !== "object") {
-    throw new Error("Expected body to be an object");
-  }
-
-  const koboldResponse = {
-    results: [{ text: body.choices[0].message.content }],
-    model: body.model,
-    ...(config.promptLogging && {
-      proxy_note: `Prompt logging is enabled on this proxy instance. See ${req.get(
-        "host"
-      )} for more information.`,
-    }),
-  };
-
-  res.send(JSON.stringify(koboldResponse));
-};
-
-const koboldOaiProxy = createProxyMiddleware({
-  target: "https://api.openai.com",
-  changeOrigin: true,
-  pathRewrite: {
-    "^/api/v1/generate": "/v1/chat/completions",
-  },
-  on: {
-    proxyReq: rewriteRequest,
-    proxyRes: createOnProxyResHandler([koboldResponseHandler]),
-    error: handleProxyError,
-  },
-  selfHandleResponse: true,
-  logger,
-});
-
-const koboldRouter = Router();
-koboldRouter.use((req, res) => {
-  logger.warn(`Unhandled kobold request: ${req.method} ${req.path}`);
-  res.status(404).json({ error: "Not found" });
-});
-
-export const kobold = koboldRouter;

src/proxy/middleware/common.ts

@@ -1,199 +1,282 @@
 import { Request, Response } from "express";
+import http from "http";
 import httpProxy from "http-proxy";
 import { ZodError } from "zod";
-import { APIFormat } from "../../shared/key-management";
+import { generateErrorMessage } from "zod-error";
 import { assertNever } from "../../shared/utils";
-import { QuotaExceededError } from "./request/apply-quota-limits";
+import { QuotaExceededError } from "./request/preprocessors/apply-quota-limits";
+import { sendErrorToClient } from "./response/error-generator";
+import { HttpError } from "../../shared/errors";
 
 const OPENAI_CHAT_COMPLETION_ENDPOINT = "/v1/chat/completions";
 const OPENAI_TEXT_COMPLETION_ENDPOINT = "/v1/completions";
+const OPENAI_EMBEDDINGS_ENDPOINT = "/v1/embeddings";
+const OPENAI_IMAGE_COMPLETION_ENDPOINT = "/v1/images/generations";
 const ANTHROPIC_COMPLETION_ENDPOINT = "/v1/complete";
+const ANTHROPIC_MESSAGES_ENDPOINT = "/v1/messages";
+const ANTHROPIC_SONNET_COMPAT_ENDPOINT = "/v1/sonnet";
+const ANTHROPIC_OPUS_COMPAT_ENDPOINT = "/v1/opus";
 
-/** Returns true if we're making a request to a completion endpoint. */
+export function isTextGenerationRequest(req: Request) {
-export function isCompletionRequest(req: Request) {
-  // 99% sure this function is not needed anymore
   return (
     req.method === "POST" &&
     [
       OPENAI_CHAT_COMPLETION_ENDPOINT,
       OPENAI_TEXT_COMPLETION_ENDPOINT,
       ANTHROPIC_COMPLETION_ENDPOINT,
+      ANTHROPIC_MESSAGES_ENDPOINT,
+      ANTHROPIC_SONNET_COMPAT_ENDPOINT,
+      ANTHROPIC_OPUS_COMPAT_ENDPOINT,
     ].some((endpoint) => req.path.startsWith(endpoint))
   );
 }
 
-export function writeErrorResponse(
+export function isImageGenerationRequest(req: Request) {
+  return (
+    req.method === "POST" &&
+    req.path.startsWith(OPENAI_IMAGE_COMPLETION_ENDPOINT)
+  );
+}
+
+export function isEmbeddingsRequest(req: Request) {
+  return (
+    req.method === "POST" && req.path.startsWith(OPENAI_EMBEDDINGS_ENDPOINT)
+  );
+}
+
+export function sendProxyError(
   req: Request,
   res: Response,
   statusCode: number,
+  statusMessage: string,
   errorPayload: Record<string, any>
 ) {
-  const errorSource = errorPayload.error?.type?.startsWith("proxy")
+  const msg =
-    ? "proxy"
+    statusCode === 500
-    : "upstream";
+      ? `The proxy encountered an error while trying to process your prompt.`
+      : `The proxy encountered an error while trying to send your prompt to the upstream service.`;
 
-  // If we're mid-SSE stream, send a data event with the error payload and end
+  sendErrorToClient({
-  // the stream. Otherwise just send a normal error response.
+    options: {
-  if (
+      format: req.inboundApi,
-    res.headersSent ||
+      title: `Proxy error (HTTP ${statusCode} ${statusMessage})`,
-    res.getHeader("content-type") === "text/event-stream"
+      message: `${msg} Further technical details are provided below.`,
-  ) {
+      obj: errorPayload,
-    const errorContent =
+      reqId: req.id,
-      statusCode === 403
+      model: req.body?.model,
-        ? JSON.stringify(errorPayload)
+    },
-        : JSON.stringify(errorPayload, null, 2);
+    req,
-
+    res,
-    const msg = buildFakeSseMessage(
+  });
-      `${errorSource} error (${statusCode})`,
-      errorContent,
-      req
-    );
-    res.write(msg);
-    res.write(`data: [DONE]\n\n`);
-    res.end();
-  } else {
-    if (req.debug) {
-      errorPayload.error.proxy_tokenizer_debug_info = req.debug;
-    }
-    res.status(statusCode).json(errorPayload);
-  }
 }
 
 export const handleProxyError: httpProxy.ErrorCallback = (err, req, res) => {
-  req.log.error({ err }, `Error during proxy request middleware`);
+  req.log.error(err, `Error during http-proxy-middleware request`);
-  handleInternalError(err, req as Request, res as Response);
+  classifyErrorAndSend(err, req as Request, res as Response);
 };
 
-export const handleInternalError = (
+export const classifyErrorAndSend = (
   err: Error,
   req: Request,
   res: Response
 ) => {
   try {
-    if (err instanceof ZodError) {
+    const { statusCode, statusMessage, userMessage, ...errorDetails } =
-      writeErrorResponse(req, res, 400, {
+      classifyError(err);
-        error: {
+    sendProxyError(req, res, statusCode, statusMessage, {
-          type: "proxy_validation_error",
+      error: { message: userMessage, ...errorDetails },
-          proxy_note: `Reverse proxy couldn't validate your request when trying to transform it. Your client may be sending invalid data.`,
+    });
-          issues: err.issues,
+  } catch (error) {
-          stack: err.stack,
+    req.log.error(error, `Error writing error response headers, giving up.`);
-          message: err.message,
+    res.end();
-        },
-      });
-    } else if (err.name === "ForbiddenError") {
-      // Spoofs a vaguely threatening OpenAI error message. Only invoked by the
-      // block-zoomers rewriter to scare off tiktokers.
-      writeErrorResponse(req, res, 403, {
-        error: {
-          type: "organization_account_disabled",
-          code: "policy_violation",
-          param: null,
-          message: err.message,
-        },
-      });
-    } else if (err instanceof QuotaExceededError) {
-      writeErrorResponse(req, res, 429, {
-        error: {
-          type: "proxy_quota_exceeded",
-          code: "quota_exceeded",
-          message: `You've exceeded your token quota for this model type.`,
-          info: err.quotaInfo,
-          stack: err.stack,
-        },
-      });
-    } else {
-      writeErrorResponse(req, res, 500, {
-        error: {
-          type: "proxy_internal_error",
-          proxy_note: `Reverse proxy encountered an error before it could reach the upstream API.`,
-          message: err.message,
-          stack: err.stack,
-        },
-      });
-    }
-  } catch (e) {
-    req.log.error(
-      { error: e },
-      `Error writing error response headers, giving up.`
-    );
   }
 };
 
-export function buildFakeSseMessage(
+function classifyError(err: Error): {
-  type: string,
+  /** HTTP status code returned to the client. */
-  string: string,
+  statusCode: number;
-  req: Request
+  /** HTTP status message returned to the client. */
-) {
+  statusMessage: string;
-  let fakeEvent;
+  /** Message displayed to the user. */
-  const useBackticks = !type.includes("403");
+  userMessage: string;
-  const msgContent = useBackticks
+  /** Short error type, e.g. "proxy_validation_error". */
-    ? `\`\`\`\n[${type}: ${string}]\n\`\`\`\n`
+  type: string;
-    : `[${type}: ${string}]`;
+} & Record<string, any> {
+  const defaultError = {
+    statusCode: 500,
+    statusMessage: "Internal Server Error",
+    userMessage: `Reverse proxy error: ${err.message}`,
+    type: "proxy_internal_error",
+    stack: err.stack,
+  };
 
-  switch (req.inboundApi) {
+  switch (err.constructor.name) {
-    case "openai":
+    case "HttpError":
-      fakeEvent = {
+      const statusCode = (err as HttpError).status;
-        id: "chatcmpl-" + req.id,
+      return {
-        object: "chat.completion.chunk",
+        statusCode,
-        created: Date.now(),
+        statusMessage: `HTTP ${statusCode} ${http.STATUS_CODES[statusCode]}`,
-        model: req.body?.model,
+        userMessage: `Reverse proxy error: ${err.message}`,
-        choices: [
+        type: "proxy_http_error",
-          {
-            delta: { content: msgContent },
-            index: 0,
-            finish_reason: type,
-          },
-        ],
       };
-      break;
+    case "BadRequestError":
-    case "openai-text":
+      return {
-      fakeEvent = {
+        statusCode: 400,
-        id: "cmpl-" + req.id,
+        statusMessage: "Bad Request",
-        object: "text_completion",
+        userMessage: `Request is not valid. (${err.message})`,
-        created: Date.now(),
+        type: "proxy_bad_request",
-        choices: [
-          { text: msgContent, index: 0, logprobs: null, finish_reason: type },
-        ],
-        model: req.body?.model,
       };
-      break;
+    case "NotFoundError":
-    case "anthropic":
+      return {
-      fakeEvent = {
+        statusCode: 404,
-        completion: msgContent,
+        statusMessage: "Not Found",
-        stop_reason: type,
+        userMessage: `Requested resource not found. (${err.message})`,
-        truncated: false, // I've never seen this be true
+        type: "proxy_not_found",
-        stop: null,
-        model: req.body?.model,
-        log_id: "proxy-req-" + req.id,
       };
-      break;
+    case "PaymentRequiredError":
-    case "google-palm":
+      return {
-      throw new Error("PaLM not supported as an inbound API format");
+        statusCode: 402,
+        statusMessage: "No Keys Available",
+        userMessage: err.message,
+        type: "proxy_no_keys_available",
+      };
+    case "ZodError":
+      const userMessage = generateErrorMessage((err as ZodError).issues, {
+        prefix: "Request validation failed. ",
+        path: { enabled: true, label: null, type: "breadcrumbs" },
+        code: { enabled: false },
+        maxErrors: 3,
+        transform: ({ issue, ...rest }) => {
+          return `At '${rest.pathComponent}': ${issue.message}`;
+        },
+      });
+      return {
+        statusCode: 400,
+        statusMessage: "Bad Request",
+        userMessage,
+        type: "proxy_validation_error",
+      };
+    case "ZoomerForbiddenError":
+      // Mimics a ban notice from OpenAI, thrown when blockZoomerOrigins blocks
+      // a request.
+      return {
+        statusCode: 403,
+        statusMessage: "Forbidden",
+        userMessage: `Your account has been disabled for violating our terms of service.`,
+        type: "organization_account_disabled",
+        code: "policy_violation",
+      };
+    case "ForbiddenError":
+      return {
+        statusCode: 403,
+        statusMessage: "Forbidden",
+        userMessage: `Request is not allowed. (${err.message})`,
+        type: "proxy_forbidden",
+      };
+    case "QuotaExceededError":
+      return {
+        statusCode: 429,
+        statusMessage: "Too Many Requests",
+        userMessage: `You've exceeded your token quota for this model type.`,
+        type: "proxy_quota_exceeded",
+        info: (err as QuotaExceededError).quotaInfo,
+      };
+    case "Error":
+      if ("code" in err) {
+        switch (err.code) {
+          case "ENOTFOUND":
+            return {
+              statusCode: 502,
+              statusMessage: "Bad Gateway",
+              userMessage: `Reverse proxy encountered a DNS error while trying to connect to the upstream service.`,
+              type: "proxy_network_error",
+              code: err.code,
+            };
+          case "ECONNREFUSED":
+            return {
+              statusCode: 502,
+              statusMessage: "Bad Gateway",
+              userMessage: `Reverse proxy couldn't connect to the upstream service.`,
+              type: "proxy_network_error",
+              code: err.code,
+            };
+          case "ECONNRESET":
+            return {
+              statusCode: 504,
+              statusMessage: "Gateway Timeout",
+              userMessage: `Reverse proxy timed out while waiting for the upstream service to respond.`,
+              type: "proxy_network_error",
+              code: err.code,
+            };
+        }
+      }
+      return defaultError;
     default:
-      assertNever(req.inboundApi);
+      return defaultError;
-  }
+  }
-  return `data: ${JSON.stringify(fakeEvent)}\n\n`;
+}
-}
+
-
+export function getCompletionFromBody(req: Request, body: Record<string, any>) {
-export function getCompletionForService({
+  const format = req.outboundApi;
-  service,
+  switch (format) {
-  body,
+    case "openai":
-  req,
+    case "mistral-ai":
-}: {
+      // Can be null if the model wants to invoke tools rather than return a
-  service: APIFormat;
+      // completion.
-  body: Record<string, any>;
+      return body.choices[0].message.content || "";
-  req?: Request;
+    case "openai-text":
-}): { completion: string; model: string } {
+      return body.choices[0].text;
-  switch (service) {
+    case "anthropic-chat":
-    case "openai":
+      if (!body.content) {
-      return { completion: body.choices[0].message.content, model: body.model };
+        req.log.error(
-    case "openai-text":
+          { body: JSON.stringify(body) },
-      return { completion: body.choices[0].text, model: body.model };
+          "Received empty Anthropic chat completion"
-    case "anthropic":
+        );
-      return { completion: body.completion.trim(), model: body.model };
+        return "";
-    case "google-palm":
+      }
-      return { completion: body.candidates[0].output, model: req?.body.model };
+      return body.content
-    default:
+        .map(({ text, type }: { type: string; text: string }) =>
-      assertNever(service);
+          type === "text" ? text : `[Unsupported content type: ${type}]`
+        )
+        .join("\n");
+    case "anthropic-text":
+      if (!body.completion) {
+        req.log.error(
+          { body: JSON.stringify(body) },
+          "Received empty Anthropic text completion"
+        );
+        return "";
+      }
+      return body.completion.trim();
+    case "google-ai":
+      if ("choices" in body) {
+        return body.choices[0].message.content;
+      }
+      return body.candidates[0].content.parts[0].text;
+    case "openai-image":
+      return body.data?.map((item: any) => item.url).join("\n");
+    default:
+      assertNever(format);
+  }
+}
+
+export function getModelFromBody(req: Request, body: Record<string, any>) {
+  const format = req.outboundApi;
+  switch (format) {
+    case "openai":
+    case "openai-text":
+    case "mistral-ai":
+      return body.model;
+    case "openai-image":
+      return req.body.model;
+    case "anthropic-chat":
+    case "anthropic-text":
+      // Anthropic confirms the model in the response, but AWS Claude doesn't.
+      return body.model || req.body.model;
+    case "google-ai":
+      // Google doesn't confirm the model in the response.
+      return req.body.model;
+    default:
+      assertNever(format);
   }
 }

src/proxy/middleware/request/add-anthropic-preamble.ts

@@ -1,49 +0,0 @@
-import { AnthropicKey, Key } from "../../../shared/key-management";
-import { isCompletionRequest } from "../common";
-import { ProxyRequestMiddleware } from ".";
-
-/**
- * Some keys require the prompt to start with `\n\nHuman:`. There is no way to
- * know this without trying to send the request and seeing if it fails. If a
- * key is marked as requiring a preamble, it will be added here.
- */
-export const addAnthropicPreamble: ProxyRequestMiddleware = (
-  _proxyReq,
-  req
-) => {
-  if (!isCompletionRequest(req) || req.key?.service !== "anthropic") {
-    return;
-  }
-
-  assertAnthropicKey(req.key);
-  
-  if (req.key.requiresPreamble) {
-    let prompt = req.body.prompt;
-    const preamble = prompt.startsWith("\n\nHuman:") ? "" : "\n\nHuman:";
-    req.log.debug({ key: req.key.hash, preamble }, "Prompt requres preamble");
-    prompt = preamble + prompt;
-
-    // Adds `Assistant:` to the end of the prompt if the turn closest to the
-    // end is from the `Human:` persona.
-    const humanIndex = prompt.lastIndexOf("\n\nHuman:");
-    const assistantIndex = prompt.lastIndexOf("\n\nAssistant:");
-    const shouldAddAssistant = humanIndex > assistantIndex;
-    req.log.debug(
-      {
-        key: req.key.hash,
-        shouldAdd: shouldAddAssistant,
-        hIndex: humanIndex,
-        aIndex: assistantIndex,
-      },
-      "Possibly adding Assistant: to prompt"
-    );
-    if (shouldAddAssistant) prompt += "\n\nAssistant:";
-    req.body.prompt = prompt;
-  }
-};
-
-function assertAnthropicKey(key: Key): asserts key is AnthropicKey {
-  if (key.service !== "anthropic") {
-    throw new Error(`Expected an Anthropic key, got '${key.service}'`);
-  }
-}

src/proxy/middleware/request/add-key.ts

@@ -1,97 +0,0 @@
-import { Key, OpenAIKey, keyPool } from "../../../shared/key-management";
-import { isCompletionRequest } from "../common";
-import { ProxyRequestMiddleware } from ".";
-import { assertNever } from "../../../shared/utils";
-
-/** Add a key that can service this request to the request object. */
-export const addKey: ProxyRequestMiddleware = (proxyReq, req) => {
-  let assignedKey: Key;
-
-  if (!isCompletionRequest(req)) {
-    // Horrible, horrible hack to stop the proxy from complaining about clients
-    // not sending a model when they are requesting the list of models (which
-    // requires a key, but obviously not a model).
-    // TODO: shouldn't even proxy /models to the upstream API, just fake it
-    // using the models our key pool has available.
-    req.body.model = "gpt-3.5-turbo";
-  }
-
-  if (!req.inboundApi || !req.outboundApi) {
-    const err = new Error(
-      "Request API format missing. Did you forget to add the request preprocessor to your router?"
-    );
-    req.log.error(
-      { in: req.inboundApi, out: req.outboundApi, path: req.path },
-      err.message
-    );
-    throw err;
-  }
-
-  if (!req.body?.model) {
-    throw new Error("You must specify a model with your request.");
-  }
-
-  // TODO: use separate middleware to deal with stream flags
-  req.isStreaming = req.body.stream === true || req.body.stream === "true";
-  req.body.stream = req.isStreaming;
-
-  if (req.inboundApi === req.outboundApi) {
-    assignedKey = keyPool.get(req.body.model);
-  } else {
-    switch (req.outboundApi) {
-      // If we are translating between API formats we may need to select a model
-      // for the user, because the provided model is for the inbound API.
-      case "anthropic":
-        assignedKey = keyPool.get("claude-v1");
-        break;
-      case "google-palm":
-        assignedKey = keyPool.get("text-bison-001");
-        delete req.body.stream;
-        break;
-      case "openai-text":
-        assignedKey = keyPool.get("gpt-3.5-turbo-instruct");
-        break;
-      case "openai":
-        throw new Error(
-          "OpenAI Chat as an API translation target is not supported"
-        );
-      default:
-        assertNever(req.outboundApi);
-    }
-  }
-
-  req.key = assignedKey;
-  req.log.info(
-    {
-      key: assignedKey.hash,
-      model: req.body?.model,
-      fromApi: req.inboundApi,
-      toApi: req.outboundApi,
-    },
-    "Assigned key to request"
-  );
-
-  // TODO: KeyProvider should assemble all necessary headers
-  switch (assignedKey.service) {
-    case "anthropic":
-      proxyReq.setHeader("X-API-Key", assignedKey.key);
-      break;
-    case "openai":
-    case "openai-text":
-      const key: OpenAIKey = assignedKey as OpenAIKey;
-      if (key.organizationId) {
-        proxyReq.setHeader("OpenAI-Organization", key.organizationId);
-      }
-      proxyReq.setHeader("Authorization", `Bearer ${assignedKey.key}`);
-      break;
-    case "google-palm":
-      const originalPath = proxyReq.path;
-      proxyReq.path = originalPath.replace(
-        /(\?.*)?$/,
-        `?key=${assignedKey.key}`
-      );
-      break;
-    default:
-      assertNever(assignedKey.service);
-  }
-};

src/proxy/middleware/request/apply-quota-limits.ts

@@ -1,30 +0,0 @@
-import { hasAvailableQuota } from "../../../shared/users/user-store";
-import { isCompletionRequest } from "../common";
-import { ProxyRequestMiddleware } from ".";
-
-export class QuotaExceededError extends Error {
-  public quotaInfo: any;
-  constructor(message: string, quotaInfo: any) {
-    super(message);
-    this.name = "QuotaExceededError";
-    this.quotaInfo = quotaInfo;
-  }
-}
-
-export const applyQuotaLimits: ProxyRequestMiddleware = (_proxyReq, req) => {
-  if (!isCompletionRequest(req) || !req.user) {
-    return;
-  }
-
-  const requestedTokens = (req.promptTokens ?? 0) + (req.outputTokens ?? 0);
-  if (!hasAvailableQuota(req.user.token, req.body.model, requestedTokens)) {
-    throw new QuotaExceededError(
-      "You have exceeded your proxy token quota for this model.",
-      {
-        quota: req.user.tokenLimits,
-        used: req.user.tokenCounts,
-        requested: requestedTokens,
-      }
-    );
-  }
-};

src/proxy/middleware/request/check-context-size.ts

@@ -1,163 +0,0 @@
-import { Request } from "express";
-import { z } from "zod";
-import { config } from "../../../config";
-import { OpenAIPromptMessage, countTokens } from "../../../shared/tokenization";
-import { RequestPreprocessor } from ".";
-import { assertNever } from "../../../shared/utils";
-
-const CLAUDE_MAX_CONTEXT = config.maxContextTokensAnthropic;
-const OPENAI_MAX_CONTEXT = config.maxContextTokensOpenAI;
-const BISON_MAX_CONTEXT = 8100;
-
-/**
- * Assigns `req.promptTokens` and `req.outputTokens` based on the request body
- * and outbound API format, which combined determine the size of the context.
- * If the context is too large, an error is thrown.
- * This preprocessor should run after any preprocessor that transforms the
- * request body.
- */
-export const checkContextSize: RequestPreprocessor = async (req) => {
-  const service = req.outboundApi;
-  let result;
-
-  switch (service) {
-    case "openai": {
-      req.outputTokens = req.body.max_tokens;
-      const prompt: OpenAIPromptMessage[] = req.body.messages;
-      result = await countTokens({ req, prompt, service });
-      break;
-    }
-    case "openai-text": {
-      req.outputTokens = req.body.max_tokens;
-      const prompt: string = req.body.prompt;
-      result = await countTokens({ req, prompt, service });
-      break;
-    }
-    case "anthropic": {
-      req.outputTokens = req.body.max_tokens_to_sample;
-      const prompt: string = req.body.prompt;
-      result = await countTokens({ req, prompt, service });
-      break;
-    }
-    case "google-palm": {
-      req.outputTokens = req.body.maxOutputTokens;
-      const prompt: string = req.body.prompt.text;
-      result = await countTokens({ req, prompt, service });
-      break;
-    }
-    default:
-      assertNever(service);
-  }
-
-  req.promptTokens = result.token_count;
-
-  // TODO: Remove once token counting is stable
-  req.log.debug({ result: result }, "Counted prompt tokens.");
-  req.debug = req.debug ?? {};
-  req.debug = { ...req.debug, ...result };
-
-  maybeTranslateOpenAIModel(req);
-  validateContextSize(req);
-};
-
-function validateContextSize(req: Request) {
-  assertRequestHasTokenCounts(req);
-  const promptTokens = req.promptTokens;
-  const outputTokens = req.outputTokens;
-  const contextTokens = promptTokens + outputTokens;
-  const model = req.body.model;
-
-  let proxyMax: number;
-  switch (req.outboundApi) {
-    case "openai":
-    case "openai-text":
-      proxyMax = OPENAI_MAX_CONTEXT;
-      break;
-    case "anthropic":
-      proxyMax = CLAUDE_MAX_CONTEXT;
-      break;
-    case "google-palm":
-      proxyMax = BISON_MAX_CONTEXT;
-      break;
-    default:
-      assertNever(req.outboundApi);
-  }
-  proxyMax ||= Number.MAX_SAFE_INTEGER;
-
-  let modelMax = 0;
-  if (model.match(/gpt-3.5-turbo-16k/)) {
-    modelMax = 16384;
-  } else if (model.match(/gpt-3.5-turbo/)) {
-    modelMax = 4096;
-  } else if (model.match(/gpt-4-32k/)) {
-    modelMax = 32768;
-  } else if (model.match(/gpt-4/)) {
-    modelMax = 8192;
-  } else if (model.match(/claude-(?:instant-)?v1(?:\.\d)?(?:-100k)/)) {
-    modelMax = 100000;
-  } else if (model.match(/claude-(?:instant-)?v1(?:\.\d)?$/)) {
-    modelMax = 9000;
-  } else if (model.match(/claude-2/)) {
-    modelMax = 100000;
-  } else if (model.match(/^text-bison-\d{3}$/)) {
-    modelMax = BISON_MAX_CONTEXT;
-  } else {
-    // Don't really want to throw here because I don't want to have to update
-    // this ASAP every time a new model is released.
-    req.log.warn({ model }, "Unknown model, using 100k token limit.");
-    modelMax = 100000;
-  }
-
-  const finalMax = Math.min(proxyMax, modelMax);
-  z.number()
-    .int()
-    .max(finalMax, {
-      message: `Your request exceeds the context size limit for this model or proxy. (max: ${finalMax} tokens, requested: ${promptTokens} prompt + ${outputTokens} output = ${contextTokens} context tokens)`,
-    })
-    .parse(contextTokens);
-
-  req.log.debug(
-    { promptTokens, outputTokens, contextTokens, modelMax, proxyMax },
-    "Prompt size validated"
-  );
-
-  req.debug.prompt_tokens = promptTokens;
-  req.debug.completion_tokens = outputTokens;
-  req.debug.max_model_tokens = modelMax;
-  req.debug.max_proxy_tokens = proxyMax;
-}
-
-function assertRequestHasTokenCounts(
-  req: Request
-): asserts req is Request & { promptTokens: number; outputTokens: number } {
-  z.object({
-    promptTokens: z.number().int().min(1),
-    outputTokens: z.number().int().min(1),
-  })
-    .nonstrict()
-    .parse({ promptTokens: req.promptTokens, outputTokens: req.outputTokens });
-}
-
-/**
- * For OpenAI-to-Anthropic requests, users can't specify the model, so we need
- * to pick one based on the final context size. Ideally this would happen in
- * the `transformOutboundPayload` preprocessor, but we don't have the context
- * size at that point (and need a transformed body to calculate it).
- */
-function maybeTranslateOpenAIModel(req: Request) {
-  if (req.inboundApi !== "openai" || req.outboundApi !== "anthropic") {
-    return;
-  }
-
-  const bigModel = process.env.CLAUDE_BIG_MODEL || "claude-v1-100k";
-  const contextSize = req.promptTokens! + req.outputTokens!;
-
-  if (contextSize > 8500) {
-    req.log.debug(
-      { model: bigModel, contextSize },
-      "Using Claude 100k model for OpenAI-to-Anthropic request"
-    );
-    req.body.model = bigModel;
-  }
-  // Small model is the default already set in `transformOutboundPayload`
-}

src/proxy/middleware/request/index.ts

@@ -2,22 +2,30 @@ import type { Request } from "express";
 import type { ClientRequest } from "http";
 import type { ProxyReqCallback } from "http-proxy";
 
-// Express middleware (runs before http-proxy-middleware, can be async)
+export { createOnProxyReqHandler } from "./onproxyreq-factory";
-export { applyQuotaLimits } from "./apply-quota-limits";
+export {
-export { createPreprocessorMiddleware } from "./preprocess";
+  createPreprocessorMiddleware,
-export { checkContextSize } from "./check-context-size";
+  createEmbeddingsPreprocessorMiddleware,
-export { setApiFormat } from "./set-api-format";
+} from "./preprocessor-factory";
-export { transformOutboundPayload } from "./transform-outbound-payload";
 
-// HPM middleware (runs on onProxyReq, cannot be async)
+// Express middleware (runs before http-proxy-middleware, can be async)
-export { addKey } from "./add-key";
+export { addAzureKey } from "./preprocessors/add-azure-key";
-export { addAnthropicPreamble } from "./add-anthropic-preamble";
+export { applyQuotaLimits } from "./preprocessors/apply-quota-limits";
-export { blockZoomerOrigins } from "./block-zoomer-origins";
+export { validateContextSize } from "./preprocessors/validate-context-size";
-export { finalizeBody } from "./finalize-body";
+export { countPromptTokens } from "./preprocessors/count-prompt-tokens";
-export { languageFilter } from "./language-filter";
+export { languageFilter } from "./preprocessors/language-filter";
-export { limitCompletions } from "./limit-completions";
+export { setApiFormat } from "./preprocessors/set-api-format";
-export { removeOriginHeaders } from "./remove-origin-headers";
+export { signAwsRequest } from "./preprocessors/sign-aws-request";
-export { transformKoboldPayload } from "./transform-kobold-payload";
+export { transformOutboundPayload } from "./preprocessors/transform-outbound-payload";
+
+// http-proxy-middleware callbacks (runs on onProxyReq, cannot be async)
+export { addKey, addKeyForEmbeddingsRequest } from "./onproxyreq/add-key";
+export { addAnthropicPreamble } from "./onproxyreq/add-anthropic-preamble";
+export { blockZoomerOrigins } from "./onproxyreq/block-zoomer-origins";
+export { checkModelFamily } from "./onproxyreq/check-model-family";
+export { finalizeBody } from "./onproxyreq/finalize-body";
+export { finalizeSignedRequest } from "./onproxyreq/finalize-signed-request";
+export { stripHeaders } from "./onproxyreq/strip-headers";
 
 /**
  * Middleware that runs prior to the request being handled by http-proxy-
@@ -36,7 +44,7 @@ export { transformKoboldPayload } from "./transform-kobold-payload";
 export type RequestPreprocessor = (req: Request) => void | Promise<void>;
 
 /**
- * Middleware that runs immediately before the request is sent to the API in
+ * Callbacks that run immediately before the request is sent to the API in
  * response to http-proxy-middleware's `proxyReq` event.
  *
  * Async functions cannot be used here as HPM's event emitter is not async and
@@ -46,4 +54,7 @@ export type RequestPreprocessor = (req: Request) => void | Promise<void>;
  * first attempt is rate limited and the request is automatically retried by the
  * request queue middleware.
  */
-export type ProxyRequestMiddleware = ProxyReqCallback<ClientRequest, Request>;
+export type HPMRequestCallback = ProxyReqCallback<ClientRequest, Request>;
+
+export const forceModel = (model: string) => (req: Request) =>
+  void (req.body.model = model);

src/proxy/middleware/request/language-filter.ts

@@ -1,56 +0,0 @@
-import { Request } from "express";
-import { config } from "../../../config";
-import { logger } from "../../../logger";
-import { assertNever } from "../../../shared/utils";
-import { isCompletionRequest } from "../common";
-import { ProxyRequestMiddleware } from ".";
-
-const DISALLOWED_REGEX =
-  /[\u2E80-\u2E99\u2E9B-\u2EF3\u2F00-\u2FD5\u3005\u3007\u3021-\u3029\u3038-\u303B\u3400-\u4DB5\u4E00-\u9FD5\uF900-\uFA6D\uFA70-\uFAD9]/;
-
-// Our shitty free-tier VMs will fall over if we test every single character in
-// each 15k character request ten times a second. So we'll just sample 20% of
-// the characters and hope that's enough.
-const containsDisallowedCharacters = (text: string) => {
-  const sampleSize = Math.ceil(text.length * 0.2);
-  const sample = text
-    .split("")
-    .sort(() => 0.5 - Math.random())
-    .slice(0, sampleSize)
-    .join("");
-  return DISALLOWED_REGEX.test(sample);
-};
-
-/** Block requests containing too many disallowed characters. */
-export const languageFilter: ProxyRequestMiddleware = (_proxyReq, req) => {
-  if (!config.rejectDisallowed) {
-    return;
-  }
-
-  if (isCompletionRequest(req)) {
-    const combinedText = getPromptFromRequest(req);
-    if (containsDisallowedCharacters(combinedText)) {
-      logger.warn(`Blocked request containing bad characters`);
-      _proxyReq.destroy(new Error(config.rejectMessage));
-    }
-  }
-};
-
-function getPromptFromRequest(req: Request) {
-  const service = req.outboundApi;
-  const body = req.body;
-  switch (service) {
-    case "anthropic":
-      return body.prompt;
-    case "openai":
-      return body.messages
-        .map((m: { content: string }) => m.content)
-        .join("\n");
-    case "openai-text":
-      return body.prompt;
-    case "google-palm":
-      return body.prompt.text;
-    default:
-      assertNever(service);
-  }
-}

src/proxy/middleware/request/limit-completions.ts

@@ -1,16 +0,0 @@
-import { isCompletionRequest } from "../common";
-import { ProxyRequestMiddleware } from ".";
-
-/**
- * Don't allow multiple completions to be requested to prevent abuse.
- * OpenAI-only, Anthropic provides no such parameter.
- **/
-export const limitCompletions: ProxyRequestMiddleware = (_proxyReq, req) => {
-  if (isCompletionRequest(req) && req.outboundApi === "openai") {
-    const originalN = req.body?.n || 1;
-    req.body.n = 1;
-    if (originalN !== req.body.n) {
-      req.log.warn(`Limiting completion choices from ${originalN} to 1`);
-    }
-  }
-};

src/proxy/middleware/request/onproxyreq-factory.ts

@@ -0,0 +1,45 @@
+import {
+  applyQuotaLimits,
+  blockZoomerOrigins,
+  checkModelFamily,
+  HPMRequestCallback,
+  stripHeaders,
+} from "./index";
+
+type ProxyReqHandlerFactoryOptions = { pipeline: HPMRequestCallback[] };
+
+/**
+ * Returns an http-proxy-middleware request handler that runs the given set of
+ * onProxyReq callback functions in sequence.
+ *
+ * These will run each time a request is proxied, including on automatic retries
+ * by the queue after encountering a rate limit.
+ */
+export const createOnProxyReqHandler = ({
+  pipeline,
+}: ProxyReqHandlerFactoryOptions): HPMRequestCallback => {
+  const callbackPipeline = [
+    checkModelFamily,
+    applyQuotaLimits,
+    blockZoomerOrigins,
+    stripHeaders,
+    ...pipeline,
+  ];
+  return (proxyReq, req, res, options) => {
+    // The streaming flag must be set before any other onProxyReq handler runs,
+    // as it may influence the behavior of subsequent handlers.
+    // Image generation requests can't be streamed.
+    // TODO: this flag is set in too many places
+    req.isStreaming =
+      req.isStreaming || req.body.stream === true || req.body.stream === "true";
+    req.body.stream = req.isStreaming;
+
+    try {
+      for (const fn of callbackPipeline) {
+        fn(proxyReq, req, res, options);
+      }
+    } catch (error) {
+      proxyReq.destroy(error);
+    }
+  };
+};

src/proxy/middleware/request/onproxyreq/add-anthropic-preamble.ts

@@ -0,0 +1,33 @@
+import { AnthropicKey, Key } from "../../../../shared/key-management";
+import { isTextGenerationRequest } from "../../common";
+import { HPMRequestCallback } from "../index";
+
+/**
+ * Some keys require the prompt to start with `\n\nHuman:`. There is no way to
+ * know this without trying to send the request and seeing if it fails. If a
+ * key is marked as requiring a preamble, it will be added here.
+ */
+export const addAnthropicPreamble: HPMRequestCallback = (_proxyReq, req) => {
+  if (
+    !isTextGenerationRequest(req) ||
+    req.key?.service !== "anthropic" ||
+    req.outboundApi !== "anthropic-text"
+  ) {
+    return;
+  }
+
+  let preamble = "";
+  let prompt = req.body.prompt;
+  assertAnthropicKey(req.key);
+  if (req.key.requiresPreamble && prompt) {
+    preamble = prompt.startsWith("\n\nHuman:") ? "" : "\n\nHuman:";
+    req.log.debug({ key: req.key.hash, preamble }, "Adding preamble to prompt");
+  }
+  req.body.prompt = preamble + prompt;
+};
+
+function assertAnthropicKey(key: Key): asserts key is AnthropicKey {
+  if (key.service !== "anthropic") {
+    throw new Error(`Expected an Anthropic key, got '${key.service}'`);
+  }
+}

src/proxy/middleware/request/onproxyreq/add-key.ts

@@ -0,0 +1,116 @@
+import { Key, OpenAIKey, keyPool } from "../../../../shared/key-management";
+import { isEmbeddingsRequest } from "../../common";
+import { HPMRequestCallback } from "../index";
+import { assertNever } from "../../../../shared/utils";
+
+export const addKey: HPMRequestCallback = (proxyReq, req) => {
+  let assignedKey: Key;
+  const { service, inboundApi, outboundApi, body } = req;
+
+  if (!inboundApi || !outboundApi) {
+    const err = new Error(
+      "Request API format missing. Did you forget to add the request preprocessor to your router?"
+    );
+    req.log.error({ inboundApi, outboundApi, path: req.path }, err.message);
+    throw err;
+  }
+
+  if (!body?.model) {
+    throw new Error("You must specify a model with your request.");
+  }
+
+  if (inboundApi === outboundApi) {
+    assignedKey = keyPool.get(body.model, service);
+  } else {
+    switch (outboundApi) {
+      // If we are translating between API formats we may need to select a model
+      // for the user, because the provided model is for the inbound API.
+      // TODO: This whole else condition is probably no longer needed since API
+      // translation now reassigns the model earlier in the request pipeline.
+      case "anthropic-chat":
+      case "anthropic-text":
+        assignedKey = keyPool.get("claude-v1", service);
+        break;
+      case "openai-text":
+        assignedKey = keyPool.get("gpt-3.5-turbo-instruct", service);
+        break;
+      case "openai-image":
+        assignedKey = keyPool.get("dall-e-3", service);
+        break;
+      case "openai":
+      case "google-ai":
+      case "mistral-ai":
+        throw new Error(
+          `add-key should not be called for outbound API ${outboundApi}`
+        );
+      default:
+        assertNever(outboundApi);
+    }
+  }
+
+  req.key = assignedKey;
+  req.log.info(
+    { key: assignedKey.hash, model: body.model, inboundApi, outboundApi },
+    "Assigned key to request"
+  );
+
+  // TODO: KeyProvider should assemble all necessary headers
+  switch (assignedKey.service) {
+    case "anthropic":
+      proxyReq.setHeader("X-API-Key", assignedKey.key);
+      break;
+    case "openai":
+      const key: OpenAIKey = assignedKey as OpenAIKey;
+      if (key.organizationId) {
+        proxyReq.setHeader("OpenAI-Organization", key.organizationId);
+      }
+      proxyReq.setHeader("Authorization", `Bearer ${assignedKey.key}`);
+      break;
+    case "mistral-ai":
+      proxyReq.setHeader("Authorization", `Bearer ${assignedKey.key}`);
+      break;
+    case "azure":
+      const azureKey = assignedKey.key;
+      proxyReq.setHeader("api-key", azureKey);
+      break;
+    case "aws":
+    case "google-ai":
+      throw new Error("add-key should not be used for this service.");
+    default:
+      assertNever(assignedKey.service);
+  }
+};
+
+/**
+ * Special case for embeddings requests which don't go through the normal
+ * request pipeline.
+ */
+export const addKeyForEmbeddingsRequest: HPMRequestCallback = (
+  proxyReq,
+  req
+) => {
+  if (!isEmbeddingsRequest(req)) {
+    throw new Error(
+      "addKeyForEmbeddingsRequest called on non-embeddings request"
+    );
+  }
+
+  if (req.inboundApi !== "openai") {
+    throw new Error("Embeddings requests must be from OpenAI");
+  }
+
+  req.body = { input: req.body.input, model: "text-embedding-ada-002" };
+
+  const key = keyPool.get("text-embedding-ada-002", "openai") as OpenAIKey;
+
+  req.key = key;
+  req.log.info(
+    { key: key.hash, toApi: req.outboundApi },
+    "Assigned Turbo key to embeddings request"
+  );
+
+  proxyReq.setHeader("Authorization", `Bearer ${key.key}`);
+  if (key.organizationId) {
+    proxyReq.setHeader("OpenAI-Organization", key.organizationId);
+  }
+};

src/proxy/middleware/request/onproxyreq/block-zoomer-origins.ts

@@ -1,12 +1,11 @@
-import { isCompletionRequest } from "../common";
+import { HPMRequestCallback } from "../index";
-import { ProxyRequestMiddleware } from ".";
 
 const DISALLOWED_ORIGIN_SUBSTRINGS = "janitorai.com,janitor.ai".split(",");
 
-class ForbiddenError extends Error {
+class ZoomerForbiddenError extends Error {
   constructor(message: string) {
     super(message);
-    this.name = "ForbiddenError";
+    this.name = "ZoomerForbiddenError";
   }
 }
 
@@ -14,11 +13,7 @@ class ForbiddenError extends Error {
  * Blocks requests from Janitor AI users with a fake, scary error message so I
  * stop getting emails asking for tech support.
  */
-export const blockZoomerOrigins: ProxyRequestMiddleware = (_proxyReq, req) => {
+export const blockZoomerOrigins: HPMRequestCallback = (_proxyReq, req) => {
-  if (!isCompletionRequest(req)) {
-    return;
-  }
-
   const origin = req.headers.origin || req.headers.referer;
   if (origin && DISALLOWED_ORIGIN_SUBSTRINGS.some((s) => origin.includes(s))) {
     // Venus-derivatives send a test prompt to check if the proxy is working.
@@ -27,7 +22,7 @@ export const blockZoomerOrigins: ProxyRequestMiddleware = (_proxyReq, req) => {
       return;
     }
 
-    throw new ForbiddenError(
+    throw new ZoomerForbiddenError(
       `Your access was terminated due to violation of our policies, please check your email for more information. If you believe this is in error and would like to appeal, please contact us through our help center at help.openai.com.`
     );
   }

src/proxy/middleware/request/onproxyreq/check-model-family.ts

@@ -0,0 +1,14 @@
+import { HPMRequestCallback } from "../index";
+import { config } from "../../../../config";
+import { ForbiddenError } from "../../../../shared/errors";
+import { getModelFamilyForRequest } from "../../../../shared/models";
+
+/**
+ * Ensures the selected model family is enabled by the proxy configuration.
+ **/
+export const checkModelFamily: HPMRequestCallback = (_proxyReq, req, res) => {
+  const family = getModelFamilyForRequest(req);
+  if (!config.allowedModelFamilies.includes(family)) {
+    throw new ForbiddenError(`Model family '${family}' is not enabled on this proxy`);
+  }
+};

src/proxy/middleware/request/onproxyreq/finalize-body.ts

@@ -1,9 +1,18 @@
 import { fixRequestBody } from "http-proxy-middleware";
-import type { ProxyRequestMiddleware } from ".";
+import type { HPMRequestCallback } from "../index";
 
 /** Finalize the rewritten request body. Must be the last rewriter. */
-export const finalizeBody: ProxyRequestMiddleware = (proxyReq, req) => {
+export const finalizeBody: HPMRequestCallback = (proxyReq, req) => {
   if (["POST", "PUT", "PATCH"].includes(req.method ?? "") && req.body) {
+    // For image generation requests, remove stream flag.
+    if (req.outboundApi === "openai-image") {
+      delete req.body.stream;
+    }
+    // For anthropic text to chat requests, remove undefined prompt.
+    if (req.outboundApi === "anthropic-chat") {
+      delete req.body.prompt;
+    }
+
     const updatedBody = JSON.stringify(req.body);
     proxyReq.setHeader("Content-Length", Buffer.byteLength(updatedBody));
     (req as any).rawBody = Buffer.from(updatedBody);

src/proxy/middleware/request/onproxyreq/finalize-signed-request.ts

@@ -0,0 +1,26 @@
+import type { HPMRequestCallback } from "../index";
+
+/**
+ * For AWS/Azure/Google requests, the body is signed earlier in the request
+ * pipeline, before the proxy middleware. This function just assigns the path
+ * and headers to the proxy request.
+ */
+export const finalizeSignedRequest: HPMRequestCallback = (proxyReq, req) => {
+  if (!req.signedRequest) {
+    throw new Error("Expected req.signedRequest to be set");
+  }
+
+  // The path depends on the selected model and the assigned key's region.
+  proxyReq.path = req.signedRequest.path;
+
+  // Amazon doesn't want extra headers, so we need to remove all of them and
+  // reassign only the ones specified in the signed request.
+  proxyReq.getRawHeaderNames().forEach(proxyReq.removeHeader.bind(proxyReq));
+  Object.entries(req.signedRequest.headers).forEach(([key, value]) => {
+    proxyReq.setHeader(key, value);
+  });
+
+  // Don't use fixRequestBody here because it adds a content-length header.
+  // Amazon doesn't want that and it breaks the signature.
+  proxyReq.write(req.signedRequest.body);
+};

src/proxy/middleware/request/onproxyreq/strip-headers.ts

@@ -0,0 +1,16 @@
+import { HPMRequestCallback } from "../index";
+
+/**
+ * Removes origin and referer headers before sending the request to the API for
+ * privacy reasons.
+ **/
+export const stripHeaders: HPMRequestCallback = (proxyReq) => {
+  proxyReq.setHeader("origin", "");
+  proxyReq.setHeader("referer", "");
+
+  proxyReq.removeHeader("cf-connecting-ip");
+  proxyReq.removeHeader("forwarded");
+  proxyReq.removeHeader("true-client-ip");
+  proxyReq.removeHeader("x-forwarded-for");
+  proxyReq.removeHeader("x-real-ip");
+};

src/proxy/middleware/request/preprocess.ts

@@ -1,36 +0,0 @@
-import { RequestHandler } from "express";
-import { handleInternalError } from "../common";
-import {
-  RequestPreprocessor,
-  checkContextSize,
-  setApiFormat,
-  transformOutboundPayload,
-} from ".";
-
-/**
- * Returns a middleware function that processes the request body into the given
- * API format, and then sequentially runs the given additional preprocessors.
- */
-export const createPreprocessorMiddleware = (
-  apiFormat: Parameters<typeof setApiFormat>[0],
-  additionalPreprocessors?: RequestPreprocessor[]
-): RequestHandler => {
-  const preprocessors: RequestPreprocessor[] = [
-    setApiFormat(apiFormat),
-    ...(additionalPreprocessors ?? []),
-    transformOutboundPayload,
-    checkContextSize,
-  ];
-
-  return async function executePreprocessors(req, res, next) {
-    try {
-      for (const preprocessor of preprocessors) {
-        await preprocessor(req);
-      }
-      next();
-    } catch (error) {
-      req.log.error(error, "Error while executing request preprocessor");
-      handleInternalError(error as Error, req, res);
-    }
-  };
-};

src/proxy/middleware/request/preprocessor-factory.ts

@@ -0,0 +1,158 @@
+import { RequestHandler } from "express";
+import { ZodIssue } from "zod";
+import { initializeSseStream } from "../../../shared/streaming";
+import { classifyErrorAndSend } from "../common";
+import {
+  RequestPreprocessor,
+  validateContextSize,
+  countPromptTokens,
+  setApiFormat,
+  transformOutboundPayload,
+  languageFilter,
+} from ".";
+
+type RequestPreprocessorOptions = {
+  /**
+   * Functions to run before the request body is transformed between API
+   * formats. Use this to change the behavior of the transformation, such as for
+   * endpoints which can accept multiple API formats.
+   */
+  beforeTransform?: RequestPreprocessor[];
+  /**
+   * Functions to run after the request body is transformed and token counts are
+   * assigned. Use this to perform validation or other actions that depend on
+   * the request body being in the final API format.
+   */
+  afterTransform?: RequestPreprocessor[];
+};
+
+/**
+ * Returns a middleware function that processes the request body into the given
+ * API format, and then sequentially runs the given additional preprocessors.
+ *
+ * These run first in the request lifecycle, a single time per request before it
+ * is added to the request queue. They aren't run again if the request is
+ * re-attempted after a rate limit.
+ *
+ * To run a preprocessor on every re-attempt, pass it to createQueueMiddleware.
+ * It will run after these preprocessors, but before the request is sent to
+ * http-proxy-middleware.
+ */
+export const createPreprocessorMiddleware = (
+  apiFormat: Parameters<typeof setApiFormat>[0],
+  { beforeTransform, afterTransform }: RequestPreprocessorOptions = {}
+): RequestHandler => {
+  const preprocessors: RequestPreprocessor[] = [
+    setApiFormat(apiFormat),
+    ...(beforeTransform ?? []),
+    transformOutboundPayload,
+    countPromptTokens,
+    languageFilter,
+    ...(afterTransform ?? []),
+    validateContextSize,
+  ];
+  return async (...args) => executePreprocessors(preprocessors, args);
+};
+
+/**
+ * Returns a middleware function that specifically prepares requests for
+ * OpenAI's embeddings API. Tokens are not counted because embeddings requests
+ * are basically free.
+ */
+export const createEmbeddingsPreprocessorMiddleware = (): RequestHandler => {
+  const preprocessors: RequestPreprocessor[] = [
+    setApiFormat({ inApi: "openai", outApi: "openai", service: "openai" }),
+    (req) => void (req.promptTokens = req.outputTokens = 0),
+  ];
+  return async (...args) => executePreprocessors(preprocessors, args);
+};
+
+async function executePreprocessors(
+  preprocessors: RequestPreprocessor[],
+  [req, res, next]: Parameters<RequestHandler>
+) {
+  handleTestMessage(req, res, next);
+  if (res.headersSent) return;
+
+  try {
+    for (const preprocessor of preprocessors) {
+      await preprocessor(req);
+    }
+    next();
+  } catch (error) {
+    if (error.constructor.name === "ZodError") {
+      const msg = error?.issues
+        ?.map((issue: ZodIssue) => issue.message)
+        .join("; ");
+      req.log.info(msg, "Prompt validation failed.");
+    } else {
+      req.log.error(error, "Error while executing request preprocessor");
+    }
+
+    // If the requested has opted into streaming, the client probably won't
+    // handle a non-eventstream response, but we haven't initialized the SSE
+    // stream yet as that is typically done later by the request queue. We'll
+    // do that here and then call classifyErrorAndSend to use the streaming
+    // error handler.
+    const { stream } = req.body;
+    const isStreaming = stream === "true" || stream === true;
+    if (isStreaming && !res.headersSent) {
+      initializeSseStream(res);
+    }
+    classifyErrorAndSend(error as Error, req, res);
+  }
+}
+
+/**
+ * Bypasses the API call and returns a test message response if the request body
+ * is a known test message from SillyTavern. Otherwise these messages just waste
+ * API request quota and confuse users when the proxy is busy, because ST always
+ * makes them with `stream: false` (which is not allowed when the proxy is busy)
+ */
+const handleTestMessage: RequestHandler = (req, res) => {
+  const { method, body } = req;
+  if (method !== "POST") {
+    return;
+  }
+
+  if (isTestMessage(body)) {
+    req.log.info({ body }, "Received test message. Skipping API call.");
+    res.json({
+      id: "test-message",
+      object: "chat.completion",
+      created: Date.now(),
+      model: body.model,
+      // openai chat
+      choices: [
+        {
+          message: { role: "assistant", content: "Hello!" },
+          finish_reason: "stop",
+          index: 0,
+        },
+      ],
+      // anthropic text
+      completion: "Hello!",
+      // anthropic chat
+      content: [{ type: "text", text: "Hello!" }],
+      proxy_note:
+        "This response was generated by the proxy's test message handler and did not go to the API.",
+    });
+  }
+};
+
+function isTestMessage(body: any) {
+  const { messages, prompt } = body;
+
+  if (messages) {
+    return (
+      messages.length === 1 &&
+      messages[0].role === "user" &&
+      messages[0].content === "Hi"
+    );
+  } else {
+    return (
+      prompt?.trim() === "Human: Hi\n\nAssistant:" ||
+      prompt?.startsWith("Hi\n\n")
+    );
+  }
+}

src/proxy/middleware/request/preprocessors/add-azure-key.ts

@@ -0,0 +1,78 @@
+import {
+  APIFormat,
+  AzureOpenAIKey,
+  keyPool,
+} from "../../../../shared/key-management";
+import { RequestPreprocessor } from "../index";
+
+export const addAzureKey: RequestPreprocessor = (req) => {
+  const validAPIs: APIFormat[] = ["openai", "openai-image"];
+  const apisValid = [req.outboundApi, req.inboundApi].every((api) =>
+    validAPIs.includes(api)
+  );
+  const serviceValid = req.service === "azure";
+  if (!apisValid || !serviceValid) {
+    throw new Error("addAzureKey called on invalid request");
+  }
+
+  if (!req.body?.model) {
+    throw new Error("You must specify a model with your request.");
+  }
+
+  const model = req.body.model.startsWith("azure-")
+    ? req.body.model
+    : `azure-${req.body.model}`;
+
+  req.key = keyPool.get(model, "azure");
+  req.body.model = model;
+
+  // Handles the sole Azure API deviation from the OpenAI spec (that I know of)
+  const notNullOrUndefined = (x: any) => x !== null && x !== undefined;
+  if ([req.body.logprobs, req.body.top_logprobs].some(notNullOrUndefined)) {
+    // OpenAI wants logprobs: true/false and top_logprobs: number
+    // Azure seems to just want to combine them into logprobs: number
+    // if (typeof req.body.logprobs === "boolean") {
+    //   req.body.logprobs = req.body.top_logprobs || undefined;
+    //   delete req.body.top_logprobs
+    // }
+
+    // Temporarily just disabling logprobs for Azure because their model support
+    // is random: `This model does not support the 'logprobs' parameter.`
+    delete req.body.logprobs;
+    delete req.body.top_logprobs;
+  }
+
+  req.log.info(
+    { key: req.key.hash, model },
+    "Assigned Azure OpenAI key to request"
+  );
+
+  const cred = req.key as AzureOpenAIKey;
+  const { resourceName, deploymentId, apiKey } = getCredentialsFromKey(cred);
+
+  const operation =
+    req.outboundApi === "openai" ? "/chat/completions" : "/images/generations";
+  const apiVersion =
+    req.outboundApi === "openai" ? "2023-09-01-preview" : "2024-02-15-preview";
+
+  req.signedRequest = {
+    method: "POST",
+    protocol: "https:",
+    hostname: `${resourceName}.openai.azure.com`,
+    path: `/openai/deployments/${deploymentId}${operation}?api-version=${apiVersion}`,
+    headers: {
+      ["host"]: `${resourceName}.openai.azure.com`,
+      ["content-type"]: "application/json",
+      ["api-key"]: apiKey,
+    },
+    body: JSON.stringify(req.body),
+  };
+};
+
+function getCredentialsFromKey(key: AzureOpenAIKey) {
+  const [resourceName, deploymentId, apiKey] = key.key.split(":");
+  if (!resourceName || !deploymentId || !apiKey) {
+    throw new Error("Assigned Azure OpenAI key is not in the correct format.");
+  }
+  return { resourceName, deploymentId, apiKey };
+}

src/proxy/middleware/request/preprocessors/add-google-ai-key.ts

@@ -0,0 +1,40 @@
+import { keyPool } from "../../../../shared/key-management";
+import { RequestPreprocessor } from "../index";
+
+export const addGoogleAIKey: RequestPreprocessor = (req) => {
+  const apisValid = req.inboundApi === "openai" && req.outboundApi === "google-ai";
+  const serviceValid = req.service === "google-ai";
+  if (!apisValid || !serviceValid) {
+    throw new Error("addGoogleAIKey called on invalid request");
+  }
+
+  if (!req.body?.model) {
+    throw new Error("You must specify a model with your request.");
+  }
+
+  const model = req.body.model;
+  req.key = keyPool.get(model, "google-ai");
+
+  req.log.info(
+    { key: req.key.hash, model },
+    "Assigned Google AI API key to request"
+  );
+
+  // https://generativelanguage.googleapis.com/v1beta/models/$MODEL_ID:generateContent?key=$API_KEY
+  // https://generativelanguage.googleapis.com/v1beta/models/$MODEL_ID:streamGenerateContent?key=${API_KEY}
+
+  req.isStreaming = req.isStreaming || req.body.stream;
+  delete req.body.stream;
+
+  req.signedRequest = {
+    method: "POST",
+    protocol: "https:",
+    hostname: "generativelanguage.googleapis.com",
+    path: `/v1beta/models/${model}:${req.isStreaming ? "streamGenerateContent" : "generateContent"}?key=${req.key.key}`,
+    headers: {
+      ["host"]: `generativelanguage.googleapis.com`,
+      ["content-type"]: "application/json",
+    },
+    body: JSON.stringify(req.body),
+  };
+};

src/proxy/middleware/request/preprocessors/apply-quota-limits.ts

@@ -0,0 +1,37 @@
+import { hasAvailableQuota } from "../../../../shared/users/user-store";
+import { isImageGenerationRequest, isTextGenerationRequest } from "../../common";
+import { HPMRequestCallback } from "../index";
+
+export class QuotaExceededError extends Error {
+  public quotaInfo: any;
+  constructor(message: string, quotaInfo: any) {
+    super(message);
+    this.name = "QuotaExceededError";
+    this.quotaInfo = quotaInfo;
+  }
+}
+
+export const applyQuotaLimits: HPMRequestCallback = (_proxyReq, req) => {
+  const subjectToQuota =
+    isTextGenerationRequest(req) || isImageGenerationRequest(req);
+  if (!subjectToQuota || !req.user) return;
+
+  const requestedTokens = (req.promptTokens ?? 0) + (req.outputTokens ?? 0);
+  if (
+    !hasAvailableQuota({
+      userToken: req.user.token,
+      model: req.body.model,
+      api: req.outboundApi,
+      requested: requestedTokens,
+    })
+  ) {
+    throw new QuotaExceededError(
+      "You have exceeded your proxy token quota for this model.",
+      {
+        quota: req.user.tokenLimits,
+        used: req.user.tokenCounts,
+        requested: requestedTokens,
+      }
+    );
+  }
+};

src/proxy/middleware/request/preprocessors/count-prompt-tokens.ts

@@ -0,0 +1,70 @@
+import { RequestPreprocessor } from "../index";
+import { countTokens } from "../../../../shared/tokenization";
+import { assertNever } from "../../../../shared/utils";
+import {
+  AnthropicChatMessage,
+  GoogleAIChatMessage,
+  MistralAIChatMessage,
+  OpenAIChatMessage,
+} from "../../../../shared/api-support";
+
+/**
+ * Given a request with an already-transformed body, counts the number of
+ * tokens and assigns the count to the request.
+ */
+export const countPromptTokens: RequestPreprocessor = async (req) => {
+  const service = req.outboundApi;
+  let result;
+
+  switch (service) {
+    case "openai": {
+      req.outputTokens = req.body.max_tokens;
+      const prompt: OpenAIChatMessage[] = req.body.messages;
+      result = await countTokens({ req, prompt, service });
+      break;
+    }
+    case "openai-text": {
+      req.outputTokens = req.body.max_tokens;
+      const prompt: string = req.body.prompt;
+      result = await countTokens({ req, prompt, service });
+      break;
+    }
+    case "anthropic-chat": {
+      req.outputTokens = req.body.max_tokens;
+      const prompt: AnthropicChatMessage[] = req.body.messages;
+      result = await countTokens({ req, prompt, service });
+      break;
+    }
+    case "anthropic-text": {
+      req.outputTokens = req.body.max_tokens_to_sample;
+      const prompt: string = req.body.prompt;
+      result = await countTokens({ req, prompt, service });
+      break;
+    }
+    case "google-ai": {
+      req.outputTokens = req.body.generationConfig.maxOutputTokens;
+      const prompt: GoogleAIChatMessage[] = req.body.contents;
+      result = await countTokens({ req, prompt, service });
+      break;
+    }
+    case "mistral-ai": {
+      req.outputTokens = req.body.max_tokens;
+      const prompt: MistralAIChatMessage[] = req.body.messages;
+      result = await countTokens({ req, prompt, service });
+      break;
+    }
+    case "openai-image": {
+      req.outputTokens = 1;
+      result = await countTokens({ req, service });
+      break;
+    }
+    default:
+      assertNever(service);
+  }
+
+  req.promptTokens = result.token_count;
+
+  req.log.debug({ result: result }, "Counted prompt tokens.");
+  req.tokenizerInfo = req.tokenizerInfo ?? {};
+  req.tokenizerInfo = { ...req.tokenizerInfo, ...result };
+};

src/proxy/middleware/request/preprocessors/language-filter.ts

@@ -0,0 +1,83 @@
+import { Request } from "express";
+import { config } from "../../../../config";
+import { assertNever } from "../../../../shared/utils";
+import { RequestPreprocessor } from "../index";
+import { BadRequestError } from "../../../../shared/errors";
+import {
+  MistralAIChatMessage,
+  OpenAIChatMessage,
+  flattenAnthropicMessages,
+} from "../../../../shared/api-support";
+
+const rejectedClients = new Map<string, number>();
+
+setInterval(() => {
+  rejectedClients.forEach((count, ip) => {
+    if (count > 0) {
+      rejectedClients.set(ip, Math.floor(count / 2));
+    } else {
+      rejectedClients.delete(ip);
+    }
+  });
+}, 30000);
+
+/**
+ * Block requests containing blacklisted phrases. Repeated rejections from the
+ * same IP address will be throttled.
+ */
+export const languageFilter: RequestPreprocessor = async (req) => {
+  if (!config.rejectPhrases.length) return;
+
+  const prompt = getPromptFromRequest(req);
+  const match = config.rejectPhrases.find((phrase) =>
+    prompt.match(new RegExp(phrase, "i"))
+  );
+
+  if (match) {
+    const ip = req.ip;
+    const rejections = (rejectedClients.get(req.ip) || 0) + 1;
+    const delay = Math.min(60000, Math.pow(2, rejections - 1) * 1000);
+    rejectedClients.set(ip, rejections);
+    req.log.warn(
+      { match, ip, rejections, delay },
+      "Prompt contains rejected phrase"
+    );
+    await new Promise((resolve) => {
+      req.res!.once("close", resolve);
+      setTimeout(resolve, delay);
+    });
+    throw new BadRequestError(config.rejectMessage);
+  }
+};
+
+function getPromptFromRequest(req: Request) {
+  const service = req.outboundApi;
+  const body = req.body;
+  switch (service) {
+    case "anthropic-chat":
+      return flattenAnthropicMessages(body.messages);
+    case "anthropic-text":
+      return body.prompt;
+    case "openai":
+    case "mistral-ai":
+      return body.messages
+        .map((msg: OpenAIChatMessage | MistralAIChatMessage) => {
+          const text = Array.isArray(msg.content)
+            ? msg.content
+                .map((c) => {
+                  if ("text" in c) return c.text;
+                })
+                .join()
+            : msg.content;
+          return `${msg.role}: ${text}`;
+        })
+        .join("\n\n");
+    case "openai-text":
+    case "openai-image":
+      return body.prompt;
+    case "google-ai":
+      return body.prompt.text;
+    default:
+      assertNever(service);
+  }
+}

src/proxy/middleware/request/preprocessors/set-api-format.ts

@@ -0,0 +1,16 @@
+import { Request } from "express";
+import { APIFormat } from "../../../../shared/key-management";
+import { LLMService } from "../../../../shared/models";
+import { RequestPreprocessor } from "../index";
+
+export const setApiFormat = (api: {
+  inApi: Request["inboundApi"];
+  outApi: APIFormat;
+  service: LLMService;
+}): RequestPreprocessor => {
+  return function configureRequestApiFormat(req) {
+    req.inboundApi = api.inApi;
+    req.outboundApi = api.outApi;
+    req.service = api.service;
+  };
+};

src/proxy/middleware/request/preprocessors/sign-aws-request.ts

@@ -0,0 +1,129 @@
+import express from "express";
+import { Sha256 } from "@aws-crypto/sha256-js";
+import { SignatureV4 } from "@smithy/signature-v4";
+import { HttpRequest } from "@smithy/protocol-http";
+import {
+  AnthropicV1TextSchema,
+  AnthropicV1MessagesSchema,
+} from "../../../../shared/api-support";
+import { keyPool } from "../../../../shared/key-management";
+import { RequestPreprocessor } from "../index";
+
+const AMZ_HOST =
+  process.env.AMZ_HOST || "bedrock-runtime.%REGION%.amazonaws.com";
+
+/**
+ * Signs an outgoing AWS request with the appropriate headers modifies the
+ * request object in place to fix the path.
+ * This happens AFTER request transformation.
+ */
+export const signAwsRequest: RequestPreprocessor = async (req) => {
+  const { model, stream } = req.body;
+  req.key = keyPool.get(model, "aws");
+
+  req.isStreaming = stream === true || stream === "true";
+
+  // same as addAnthropicPreamble for non-AWS requests, but has to happen here
+  if (req.outboundApi === "anthropic-text") {
+    let preamble = req.body.prompt.startsWith("\n\nHuman:") ? "" : "\n\nHuman:";
+    req.body.prompt = preamble + req.body.prompt;
+  }
+
+  // AWS uses mostly the same parameters as Anthropic, with a few removed params
+  // and much stricter validation on unused parameters. Rather than treating it
+  // as a separate schema we will use the anthropic ones and strip the unused
+  // parameters.
+  // TODO: This should happen in transform-outbound-payload.ts
+  let strippedParams: Record<string, unknown>;
+  if (req.outboundApi === "anthropic-chat") {
+    strippedParams = AnthropicV1MessagesSchema.pick({
+      messages: true,
+      max_tokens: true,
+      stop_sequences: true,
+      temperature: true,
+      top_k: true,
+      top_p: true,
+    })
+      .strip()
+      .parse(req.body);
+    strippedParams.anthropic_version = "bedrock-2023-05-31";
+  } else {
+    strippedParams = AnthropicV1TextSchema.pick({
+      prompt: true,
+      max_tokens_to_sample: true,
+      stop_sequences: true,
+      temperature: true,
+      top_k: true,
+      top_p: true,
+    })
+      .strip()
+      .parse(req.body);
+  }
+
+  const credential = getCredentialParts(req);
+  const host = AMZ_HOST.replace("%REGION%", credential.region);
+  // AWS only uses 2023-06-01 and does not actually check this header, but we
+  // set it so that the stream adapter always selects the correct transformer.
+  req.headers["anthropic-version"] = "2023-06-01";
+
+  // Uses the AWS SDK to sign a request, then modifies our HPM proxy request
+  // with the headers generated by the SDK.
+  const newRequest = new HttpRequest({
+    method: "POST",
+    protocol: "https:",
+    hostname: host,
+    path: `/model/${model}/invoke${stream ? "-with-response-stream" : ""}`,
+    headers: {
+      ["Host"]: host,
+      ["content-type"]: "application/json",
+    },
+    body: JSON.stringify(strippedParams),
+  });
+
+  if (stream) {
+    newRequest.headers["x-amzn-bedrock-accept"] = "application/json";
+  } else {
+    newRequest.headers["accept"] = "*/*";
+  }
+
+  const { key, body, inboundApi, outboundApi } = req;
+  req.log.info(
+    { key: key.hash, model: body.model, inboundApi, outboundApi },
+    "Assigned AWS credentials to request"
+  );
+
+  req.signedRequest = await sign(newRequest, getCredentialParts(req));
+};
+
+type Credential = {
+  accessKeyId: string;
+  secretAccessKey: string;
+  region: string;
+};
+
+function getCredentialParts(req: express.Request): Credential {
+  const [accessKeyId, secretAccessKey, region] = req.key!.key.split(":");
+
+  if (!accessKeyId || !secretAccessKey || !region) {
+    req.log.error(
+      { key: req.key!.hash },
+      "AWS_CREDENTIALS isn't correctly formatted; refer to the docs"
+    );
+    throw new Error("The key assigned to this request is invalid.");
+  }
+
+  return { accessKeyId, secretAccessKey, region };
+}
+
+async function sign(request: HttpRequest, credential: Credential) {
+  const { accessKeyId, secretAccessKey, region } = credential;
+
+  const signer = new SignatureV4({
+    sha256: Sha256,
+    credentials: { accessKeyId, secretAccessKey },
+    region,
+    service: "bedrock",
+  });
+
+  return signer.sign(request);
+}

src/proxy/middleware/request/preprocessors/transform-outbound-payload.ts

@@ -0,0 +1,57 @@
+import {
+  API_REQUEST_VALIDATORS,
+  API_REQUEST_TRANSFORMERS,
+} from "../../../../shared/api-support";
+import { BadRequestError } from "../../../../shared/errors";
+import {
+  isImageGenerationRequest,
+  isTextGenerationRequest,
+} from "../../common";
+import { RequestPreprocessor } from "../index";
+import { fixMistralPrompt } from "../../../../shared/api-support/kits/mistral-ai/request-transformers";
+
+/** Transforms an incoming request body to one that matches the target API. */
+export const transformOutboundPayload: RequestPreprocessor = async (req) => {
+  const sameService = req.inboundApi === req.outboundApi;
+  const alreadyTransformed = req.retryCount > 0;
+  const notTransformable =
+    !isTextGenerationRequest(req) && !isImageGenerationRequest(req);
+
+  if (alreadyTransformed || notTransformable) return;
+
+  // TODO: this should be an APIFormatTransformer
+  if (req.inboundApi === "mistral-ai") {
+    const messages = req.body.messages;
+    req.body.messages = fixMistralPrompt(messages);
+    req.log.info(
+      { old: messages.length, new: req.body.messages.length },
+      "Fixed Mistral prompt"
+    );
+  }
+
+  if (sameService) {
+    const result = API_REQUEST_VALIDATORS[req.inboundApi].safeParse(req.body);
+    if (!result.success) {
+      req.log.warn(
+        { issues: result.error.issues, body: req.body },
+        "Request validation failed"
+      );
+      throw result.error;
+    }
+    req.body = result.data;
+    return;
+  }
+
+  const transformation = `${req.inboundApi}->${req.outboundApi}` as const;
+  const transFn = API_REQUEST_TRANSFORMERS[transformation];
+
+  if (transFn) {
+    req.log.info({ transformation }, "Transforming request");
+    req.body = await transFn(req);
+    return;
+  }
+
+  throw new BadRequestError(
+    `${transformation} proxying is not supported. Make sure your client is configured to send requests in the correct format and to the correct endpoint.`
+  );
+};

src/proxy/middleware/request/preprocessors/validate-context-size.ts

@@ -0,0 +1,120 @@
+import { Request } from "express";
+import { z } from "zod";
+import { config } from "../../../../config";
+import { assertNever } from "../../../../shared/utils";
+import { RequestPreprocessor } from "../index";
+
+const CLAUDE_MAX_CONTEXT = config.maxContextTokensAnthropic;
+const OPENAI_MAX_CONTEXT = config.maxContextTokensOpenAI;
+const GOOGLE_AI_MAX_CONTEXT = 32000;
+const MISTRAL_AI_MAX_CONTENT = 32768;
+
+/**
+ * Assigns `req.promptTokens` and `req.outputTokens` based on the request body
+ * and outbound API format, which combined determine the size of the context.
+ * If the context is too large, an error is thrown.
+ * This preprocessor should run after any preprocessor that transforms the
+ * request body.
+ */
+export const validateContextSize: RequestPreprocessor = async (req) => {
+  assertRequestHasTokenCounts(req);
+  const promptTokens = req.promptTokens;
+  const outputTokens = req.outputTokens;
+  const contextTokens = promptTokens + outputTokens;
+  const model = req.body.model;
+
+  let proxyMax: number;
+  switch (req.outboundApi) {
+    case "openai":
+    case "openai-text":
+      proxyMax = OPENAI_MAX_CONTEXT;
+      break;
+    case "anthropic-chat":
+    case "anthropic-text":
+      proxyMax = CLAUDE_MAX_CONTEXT;
+      break;
+    case "google-ai":
+      proxyMax = GOOGLE_AI_MAX_CONTEXT;
+      break;
+    case "mistral-ai":
+      proxyMax = MISTRAL_AI_MAX_CONTENT;
+      break;
+    case "openai-image":
+      return;
+    default:
+      assertNever(req.outboundApi);
+  }
+  proxyMax ||= Number.MAX_SAFE_INTEGER;
+
+  let modelMax: number;
+  if (model.match(/gpt-3.5-turbo-16k/)) {
+    modelMax = 16384;
+  } else if (model.match(/gpt-4-turbo(-preview)?$/)) {
+    modelMax = 131072;
+  } else if (model.match(/gpt-4-(0125|1106)(-preview)?$/)) {
+    modelMax = 131072;
+  } else if (model.match(/^gpt-4(-\d{4})?-vision(-preview)?$/)) {
+    modelMax = 131072;
+  } else if (model.match(/gpt-3.5-turbo/)) {
+    modelMax = 4096;
+  } else if (model.match(/gpt-4-32k/)) {
+    modelMax = 32768;
+  } else if (model.match(/gpt-4/)) {
+    modelMax = 8192;
+  } else if (model.match(/^claude-(?:instant-)?v1(?:\.\d)?-100k/)) {
+    modelMax = 100000;
+  } else if (model.match(/^claude-(?:instant-)?v1(?:\.\d)?$/)) {
+    modelMax = 9000;
+  } else if (model.match(/^claude-2\.0/)) {
+    modelMax = 100000;
+  } else if (model.match(/^claude-2/)) {
+    modelMax = 200000;
+  } else if (model.match(/^claude-3/)) {
+    modelMax = 200000;
+  } else if (model.match(/^gemini-\d{3}$/)) {
+    modelMax = GOOGLE_AI_MAX_CONTEXT;
+  } else if (model.match(/^mistral-(tiny|small|medium)$/)) {
+    modelMax = MISTRAL_AI_MAX_CONTENT;
+  } else if (model.match(/^anthropic\.claude-3-sonnet/)) {
+    modelMax = 200000;
+  } else if (model.match(/^anthropic\.claude-v2:\d/)) {
+    modelMax = 200000;
+  } else if (model.match(/^anthropic\.claude/)) {
+    // Not sure if AWS Claude has the same context limit as Anthropic Claude.
+    modelMax = 100000;
+  } else {
+    req.log.warn({ model }, "Unknown model, using 200k token limit.");
+    modelMax = 200000;
+  }
+
+  const finalMax = Math.min(proxyMax, modelMax);
+  z.object({
+    tokens: z
+      .number()
+      .int()
+      .max(finalMax, {
+        message: `Your request exceeds the context size limit. (max: ${finalMax} tokens, requested: ${promptTokens} prompt + ${outputTokens} output = ${contextTokens} context tokens)`,
+      }),
+  }).parse({ tokens: contextTokens });
+
+  req.log.debug(
+    { promptTokens, outputTokens, contextTokens, modelMax, proxyMax },
+    "Prompt size validated"
+  );
+
+  req.tokenizerInfo.prompt_tokens = promptTokens;
+  req.tokenizerInfo.completion_tokens = outputTokens;
+  req.tokenizerInfo.max_model_tokens = modelMax;
+  req.tokenizerInfo.max_proxy_tokens = proxyMax;
+};
+
+function assertRequestHasTokenCounts(
+  req: Request
+): asserts req is Request & { promptTokens: number; outputTokens: number } {
+  z.object({
+    promptTokens: z.number().int().min(1),
+    outputTokens: z.number().int().min(1),
+  })
+    .nonstrict()
+    .parse({ promptTokens: req.promptTokens, outputTokens: req.outputTokens });
+}

src/proxy/middleware/request/remove-origin-headers.ts

@@ -1,10 +0,0 @@
-import { ProxyRequestMiddleware } from ".";
-
-/**
- * Removes origin and referer headers before sending the request to the API for
- * privacy reasons.
- **/
-export const removeOriginHeaders: ProxyRequestMiddleware = (proxyReq) => {
-  proxyReq.setHeader("origin", "");
-  proxyReq.setHeader("referer", "");
-};

src/proxy/middleware/request/set-api-format.ts

@@ -1,13 +0,0 @@
-import { Request } from "express";
-import { APIFormat } from "../../../shared/key-management";
-import { RequestPreprocessor } from ".";
-
-export const setApiFormat = (api: {
-  inApi: Request["inboundApi"];
-  outApi: APIFormat;
-}): RequestPreprocessor => {
-  return (req) => {
-    req.inboundApi = api.inApi;
-    req.outboundApi = api.outApi;
-  };
-};

src/proxy/middleware/request/transform-kobold-payload.ts

@@ -1,112 +0,0 @@
-/**
- * Transforms a KoboldAI payload into an OpenAI payload.
- * @deprecated Kobold input format isn't supported anymore as all popular
- * frontends support reverse proxies or changing their base URL. It adds too
- * many edge cases to be worth maintaining and doesn't work with newer features.
- */
-import { logger } from "../../../logger";
-import type { ProxyRequestMiddleware } from ".";
-
-// Kobold requests look like this:
-// body:
-// {
-//   prompt: "Aqua is character from Konosuba anime. Aqua is a goddess, before life in the Fantasy World, she was a goddess of water who guided humans to the afterlife.  Aqua looks like young woman with beauty no human could match. Aqua has light blue hair, blue eyes, slim figure, long legs, wide hips, blue waist-long hair that is partially tied into a loop with a spherical clip. Aqua's measurements are 83-56-83 cm. Aqua's height 157cm. Aqua wears sleeveless dark-blue dress with white trimmings, extremely short dark blue miniskirt, green bow around her chest with a blue gem in the middle, detached white sleeves with blue and golden trimmings, thigh-high blue heeled boots over white stockings with blue trimmings. Aqua is very strong in water magic, but a little stupid, so she does not always use it to the place. Aqua is high-spirited, cheerful, carefree. Aqua rarely thinks about the consequences of her actions and always acts or speaks on her whims. Because very easy to taunt Aqua with jeers or lure her with praises.\n" +
-//     "Aqua's personality: high-spirited, likes to party, carefree, cheerful.\n" +
-//     'Circumstances and context of the dialogue: Aqua is standing in the city square and is looking for new followers\n' +
-//     'This is how Aqua should talk\n' +
-//     'You: Hi Aqua, I heard you like to spend time in the pub.\n' +
-//     "Aqua: *excitedly* Oh my goodness, yes! I just love spending time at the pub! It's so much fun to talk to all the adventurers and hear about their exciting adventures! And you are?\n" +
-//     "You: I'm a new here and I wanted to ask for your advice.\n" +
-//     'Aqua: *giggles* Oh, advice! I love giving advice! And in gratitude for that, treat me to a drink! *gives signals to the bartender*\n' +
-//     'This is how Aqua should talk\n' +
-//     'You: Hello\n' +
-//     "Aqua: *excitedly* Hello there, dear! Are you new to Axel? Don't worry, I, Aqua the goddess of water, am here to help you! Do you need any assistance? And may I say, I look simply radiant today! *strikes a pose and looks at you with puppy eyes*\n" +
-//     '\n' +
-//     'Then the roleplay chat between You and Aqua begins.\n' +
-//     "Aqua: *She is in the town square of a city named Axel. It's morning on a Saturday and she suddenly notices a person who looks like they don't know what they're doing. She approaches him and speaks* \n" +
-//     '\n' +
-//     `"Are you new here? Do you need help? Don't worry! I, Aqua the Goddess of Water, shall help you! Do I look beautiful?" \n` +
-//     '\n' +
-//     '*She strikes a pose and looks at him with puppy eyes.*\n' +
-//     'You: test\n' +
-//     'You: test\n' +
-//     'You: t\n' +
-//     'You: test\n',
-//   use_story: false,
-//   use_memory: false,
-//   use_authors_note: false,
-//   use_world_info: false,
-//   max_context_length: 2048,
-//   max_length: 180,
-//   rep_pen: 1.1,
-//   rep_pen_range: 1024,
-//   rep_pen_slope: 0.9,
-//   temperature: 0.65,
-//   tfs: 0.9,
-//   top_a: 0,
-//   top_k: 0,
-//   top_p: 0.9,
-//   typical: 1,
-//   sampler_order: [
-//     6, 0, 1, 2,
-//     3, 4, 5
-//   ],
-//   singleline: false
-// }
-
-// OpenAI expects this body:
-// { model: 'gpt-3.5-turbo', temperature: 0.65, top_p: 0.9, max_tokens: 180, messages }
-// there's also a frequency_penalty but it's not clear how that maps to kobold's
-// rep_pen.
-
-// messages is an array of { role: "system" | "assistant" | "user", content: ""}
-// kobold only sends us the entire prompt. we can try to split the last two
-// lines into user and assistant messages, but that's not always correct. For
-// now it will have to do.
-
-/**
- * Transforms a KoboldAI payload into an OpenAI payload.
- * @deprecated Probably doesn't work anymore, idk.
- **/
-export const transformKoboldPayload: ProxyRequestMiddleware = (
-  _proxyReq,
-  req
-) => {
-  // if (req.inboundApi !== "kobold") {
-  //   throw new Error("transformKoboldPayload called for non-kobold request.");
-  // }
-
-  const { body } = req;
-  const { prompt, max_length, rep_pen, top_p, temperature } = body;
-
-  if (!max_length) {
-    logger.error("KoboldAI request missing max_length.");
-    throw new Error("You must specify a max_length parameter.");
-  }
-
-  const promptLines = prompt.split("\n");
-  // The very last line is the contentless "Assistant: " hint to the AI.
-  // Tavern just leaves an empty line, Agnai includes the AI's name.
-  const assistantHint = promptLines.pop();
-  // The second-to-last line is the user's prompt, generally.
-  const userPrompt = promptLines.pop();
-  const messages = [
-    { role: "system", content: promptLines.join("\n") },
-    { role: "user", content: userPrompt },
-    { role: "assistant", content: assistantHint },
-  ];
-
-  // Kobold doesn't select a model. If the addKey rewriter assigned us a GPT-4
-  // key, use that. Otherwise, use GPT-3.5-turbo.
-
-  const model = "gpt-4";
-  const newBody = {
-    model,
-    temperature,
-    top_p,
-    frequency_penalty: rep_pen, // remove this if model turns schizo
-    max_tokens: max_length,
-    messages,
-  };
-  req.body = newBody;
-};

src/proxy/middleware/request/transform-outbound-payload.ts

@@ -1,336 +0,0 @@
-import { Request } from "express";
-import { z } from "zod";
-import { config } from "../../../config";
-import { OpenAIPromptMessage } from "../../../shared/tokenization";
-import { isCompletionRequest } from "../common";
-import { RequestPreprocessor } from ".";
-import { APIFormat } from "../../../shared/key-management";
-
-const CLAUDE_OUTPUT_MAX = config.maxOutputTokensAnthropic;
-const OPENAI_OUTPUT_MAX = config.maxOutputTokensOpenAI;
-
-// https://console.anthropic.com/docs/api/reference#-v1-complete
-const AnthropicV1CompleteSchema = z.object({
-  model: z.string().regex(/^claude-/, "Model must start with 'claude-'"),
-  prompt: z.string({
-    required_error:
-      "No prompt found. Are you sending an OpenAI-formatted request to the Claude endpoint?",
-  }),
-  max_tokens_to_sample: z.coerce
-    .number()
-    .int()
-    .transform((v) => Math.min(v, CLAUDE_OUTPUT_MAX)),
-  stop_sequences: z.array(z.string()).optional(),
-  stream: z.boolean().optional().default(false),
-  temperature: z.coerce.number().optional().default(1),
-  top_k: z.coerce.number().optional().default(-1),
-  top_p: z.coerce.number().optional().default(-1),
-  metadata: z.any().optional(),
-});
-
-// https://platform.openai.com/docs/api-reference/chat/create
-const OpenAIV1ChatCompletionSchema = z.object({
-  model: z.string().regex(/^gpt/, "Model must start with 'gpt-'"),
-  messages: z.array(
-    z.object({
-      role: z.enum(["system", "user", "assistant"]),
-      content: z.string(),
-      name: z.string().optional(),
-    }),
-    {
-      required_error:
-        "No `messages` found. Ensure you've set the correct completion endpoint.",
-      invalid_type_error:
-        "Messages were not formatted correctly. Refer to the OpenAI Chat API documentation for more information.",
-    }
-  ),
-  temperature: z.number().optional().default(1),
-  top_p: z.number().optional().default(1),
-  n: z
-    .literal(1, {
-      errorMap: () => ({
-        message: "You may only request a single completion at a time.",
-      }),
-    })
-    .optional(),
-  stream: z.boolean().optional().default(false),
-  stop: z.union([z.string(), z.array(z.string())]).optional(),
-  max_tokens: z.coerce
-    .number()
-    .int()
-    .nullish()
-    .default(16)
-    .transform((v) => Math.min(v ?? OPENAI_OUTPUT_MAX, OPENAI_OUTPUT_MAX)),
-  frequency_penalty: z.number().optional().default(0),
-  presence_penalty: z.number().optional().default(0),
-  logit_bias: z.any().optional(),
-  user: z.string().optional(),
-});
-
-const OpenAIV1TextCompletionSchema = z
-  .object({
-    model: z
-      .string()
-      .regex(
-        /^gpt-3.5-turbo-instruct/,
-        "Model must start with 'gpt-3.5-turbo-instruct'"
-      ),
-    prompt: z.string({
-      required_error:
-        "No `prompt` found. Ensure you've set the correct completion endpoint.",
-    }),
-    logprobs: z.number().int().nullish().default(null),
-    echo: z.boolean().optional().default(false),
-    best_of: z.literal(1).optional(),
-    stop: z.union([z.string(), z.array(z.string()).max(4)]).optional(),
-    suffix: z.string().optional(),
-  })
-  .merge(OpenAIV1ChatCompletionSchema.omit({ messages: true }));
-
-// https://developers.generativeai.google/api/rest/generativelanguage/models/generateText
-const PalmV1GenerateTextSchema = z.object({
-  model: z.string().regex(/^\w+-bison-\d{3}$/),
-  prompt: z.object({ text: z.string() }),
-  temperature: z.number().optional(),
-  maxOutputTokens: z.coerce
-    .number()
-    .int()
-    .optional()
-    .default(16)
-    .transform((v) => Math.min(v, 1024)), // TODO: Add config
-  candidateCount: z.literal(1).optional(),
-  topP: z.number().optional(),
-  topK: z.number().optional(),
-  safetySettings: z.array(z.object({})).max(0).optional(),
-  stopSequences: z.array(z.string()).max(5).optional(),
-});
-
-const VALIDATORS: Record<APIFormat, z.ZodSchema<any>> = {
-  anthropic: AnthropicV1CompleteSchema,
-  openai: OpenAIV1ChatCompletionSchema,
-  "openai-text": OpenAIV1TextCompletionSchema,
-  "google-palm": PalmV1GenerateTextSchema,
-};
-
-/** Transforms an incoming request body to one that matches the target API. */
-export const transformOutboundPayload: RequestPreprocessor = async (req) => {
-  const sameService = req.inboundApi === req.outboundApi;
-  const alreadyTransformed = req.retryCount > 0;
-  const notTransformable = !isCompletionRequest(req);
-
-  if (alreadyTransformed || notTransformable) {
-    return;
-  }
-
-  if (sameService) {
-    const result = VALIDATORS[req.inboundApi].safeParse(req.body);
-    if (!result.success) {
-      req.log.error(
-        { issues: result.error.issues, body: req.body },
-        "Request validation failed"
-      );
-      throw result.error;
-    }
-    req.body = result.data;
-    return;
-  }
-
-  if (req.inboundApi === "openai" && req.outboundApi === "anthropic") {
-    req.body = openaiToAnthropic(req);
-    return;
-  }
-
-  if (req.inboundApi === "openai" && req.outboundApi === "google-palm") {
-    req.body = openaiToPalm(req);
-    return;
-  }
-
-  if (req.inboundApi === "openai" && req.outboundApi === "openai-text") {
-    req.body = openaiToOpenaiText(req);
-    return;
-  }
-
-  throw new Error(
-    `'${req.inboundApi}' -> '${req.outboundApi}' request proxying is not supported. Make sure your client is configured to use the correct API.`
-  );
-};
-
-function openaiToAnthropic(req: Request) {
-  const { body } = req;
-  const result = OpenAIV1ChatCompletionSchema.safeParse(body);
-  if (!result.success) {
-    req.log.error(
-      { issues: result.error.issues, body },
-      "Invalid OpenAI-to-Anthropic request"
-    );
-    throw result.error;
-  }
-
-  // Anthropic has started versioning their API, indicated by an HTTP header
-  // `anthropic-version`. The new June 2023 version is not backwards compatible
-  // with our OpenAI-to-Anthropic transformations so we need to explicitly
-  // request the older version for now. 2023-01-01 will be removed in September.
-  // https://docs.anthropic.com/claude/reference/versioning
-  req.headers["anthropic-version"] = "2023-01-01";
-
-  const { messages, ...rest } = result.data;
-  const prompt = openAIMessagesToClaudePrompt(messages);
-
-  let stops = rest.stop
-    ? Array.isArray(rest.stop)
-      ? rest.stop
-      : [rest.stop]
-    : [];
-  // Recommended by Anthropic
-  stops.push("\n\nHuman:");
-  // Helps with jailbreak prompts that send fake system messages and multi-bot
-  // chats that prefix bot messages with "System: Respond as <bot name>".
-  stops.push("\n\nSystem:");
-  // Remove duplicates
-  stops = [...new Set(stops)];
-
-  return {
-    ...rest,
-    // Model may be overridden in `calculate-context-size.ts` to avoid having
-    // a circular dependency (`calculate-context-size.ts` needs an already-
-    // transformed request body to count tokens, but this function would like
-    // to know the count to select a model).
-    model: process.env.CLAUDE_SMALL_MODEL || "claude-v1",
-    prompt: prompt,
-    max_tokens_to_sample: rest.max_tokens,
-    stop_sequences: stops,
-  };
-}
-
-function openaiToOpenaiText(req: Request) {
-  const { body } = req;
-  const result = OpenAIV1ChatCompletionSchema.safeParse(body);
-  if (!result.success) {
-    req.log.error(
-      { issues: result.error.issues, body },
-      "Invalid OpenAI-to-OpenAI-text request"
-    );
-    throw result.error;
-  }
-
-  const { messages, ...rest } = result.data;
-  const prompt = flattenOpenAiChatMessages(messages);
-
-  let stops = rest.stop
-    ? Array.isArray(rest.stop)
-      ? rest.stop
-      : [rest.stop]
-    : [];
-  stops.push("\n\nUser:");
-  stops = [...new Set(stops)];
-
-  const transformed = { ...rest, prompt: prompt, stop: stops };
-  const validated = OpenAIV1TextCompletionSchema.parse(transformed);
-  return validated;
-}
-
-function openaiToPalm(req: Request): z.infer<typeof PalmV1GenerateTextSchema> {
-  const { body } = req;
-  const result = OpenAIV1ChatCompletionSchema.safeParse({
-    ...body,
-    model: "text-bison-001",
-  });
-  if (!result.success) {
-    req.log.error(
-      { issues: result.error.issues, body },
-      "Invalid OpenAI-to-Palm request"
-    );
-    throw result.error;
-  }
-
-  const { messages, ...rest } = result.data;
-  const prompt = flattenOpenAiChatMessages(messages);
-
-  let stops = rest.stop
-    ? Array.isArray(rest.stop)
-      ? rest.stop
-      : [rest.stop]
-    : [];
-
-  stops.push("\n\nUser:");
-  stops = [...new Set(stops)];
-
-  z.array(z.string()).max(5).parse(stops);
-
-  return {
-    prompt: { text: prompt },
-    maxOutputTokens: rest.max_tokens,
-    stopSequences: stops,
-    model: "text-bison-001",
-    topP: rest.top_p,
-    temperature: rest.temperature,
-    safetySettings: [
-      { category: "HARM_CATEGORY_UNSPECIFIED", threshold: "BLOCK_NONE" },
-      { category: "HARM_CATEGORY_DEROGATORY", threshold: "BLOCK_NONE" },
-      { category: "HARM_CATEGORY_TOXICITY", threshold: "BLOCK_NONE" },
-      { category: "HARM_CATEGORY_VIOLENCE", threshold: "BLOCK_NONE" },
-      { category: "HARM_CATEGORY_SEXUAL", threshold: "BLOCK_NONE" },
-      { category: "HARM_CATEGORY_MEDICAL", threshold: "BLOCK_NONE" },
-      { category: "HARM_CATEGORY_DANGEROUS", threshold: "BLOCK_NONE" },
-    ],
-  };
-}
-
-export function openAIMessagesToClaudePrompt(messages: OpenAIPromptMessage[]) {
-  return (
-    messages
-      .map((m) => {
-        let role: string = m.role;
-        if (role === "assistant") {
-          role = "Assistant";
-        } else if (role === "system") {
-          role = "System";
-        } else if (role === "user") {
-          role = "Human";
-        }
-        // https://console.anthropic.com/docs/prompt-design
-        // `name` isn't supported by Anthropic but we can still try to use it.
-        return `\n\n${role}: ${m.name?.trim() ? `(as ${m.name}) ` : ""}${
-          m.content
-        }`;
-      })
-      .join("") + "\n\nAssistant:"
-  );
-}
-
-function flattenOpenAiChatMessages(messages: OpenAIPromptMessage[]) {
-  // Temporary to allow experimenting with prompt strategies
-  const PROMPT_VERSION: number = 1;
-  switch (PROMPT_VERSION) {
-    case 1:
-      return (
-        messages
-          .map((m) => {
-            // Claude-style human/assistant turns
-            let role: string = m.role;
-            if (role === "assistant") {
-              role = "Assistant";
-            } else if (role === "system") {
-              role = "System";
-            } else if (role === "user") {
-              role = "User";
-            }
-            return `\n\n${role}: ${m.content}`;
-          })
-          .join("") + "\n\nAssistant:"
-      );
-    case 2:
-      return messages
-        .map((m) => {
-          // Claude without prefixes (except system) and no Assistant priming
-          let role: string = "";
-          if (role === "system") {
-            role = "System: ";
-          }
-          return `\n\n${role}${m.content}`;
-        })
-        .join("");
-    default:
-      throw new Error(`Unknown prompt version: ${PROMPT_VERSION}`);
-  }
-}

src/proxy/middleware/response/error-generator.ts

@@ -0,0 +1,339 @@
+import express from "express";
+import { APIFormat } from "../../../shared/key-management";
+import { assertNever } from "../../../shared/utils";
+import { initializeSseStream } from "../../../shared/streaming";
+
+function getMessageContent({
+  title,
+  message,
+  obj,
+}: {
+  title: string;
+  message: string;
+  obj?: Record<string, any>;
+}) {
+  /*
+  Constructs a Markdown-formatted message that renders semi-nicely in most chat
+  frontends. For example:
+  
+  **Proxy error (HTTP 404 Not Found)**
+  The proxy encountered an error while trying to send your prompt to the upstream service. Further technical details are provided below.
+  ***
+  *The requested Claude model might not exist, or the key might not be provisioned for it.*
+  ```
+  {
+   "type": "error",
+   "error": {
+     "type": "not_found_error",
+     "message": "model: some-invalid-model-id",
+    },
+   "proxy_note": "The requested Claude model might not exist, or the key might not be provisioned for it."
+  }
+  ```
+   */
+  const note = obj?.proxy_note || obj?.error?.message || "";
+  const friendlyMessage = note ? `${message}\n\n***\n\n*${note}*` : message;
+  const details = JSON.parse(JSON.stringify(obj ?? {}));
+  let stack = "";
+  if (details.stack) {
+    stack = `\n\nInclude this trace when reporting an issue.\n\`\`\`\n${details.stack}\n\`\`\``;
+    delete details.stack;
+  }
+  return `\n\n**${title}**\n${friendlyMessage}${
+    obj ? `\n\`\`\`\n${JSON.stringify(obj, null, 2)}\n\`\`\`\n${stack}` : ""
+  }`;
+}
+
+type ErrorGeneratorOptions = {
+  format: APIFormat | "unknown";
+  title: string;
+  message: string;
+  obj?: object;
+  reqId: string | number | object;
+  model?: string;
+  statusCode?: number;
+};
+
+export function tryInferFormat(body: any): APIFormat | "unknown" {
+  if (typeof body !== "object" || !body.model) {
+    return "unknown";
+  }
+
+  if (body.model.includes("gpt")) {
+    return "openai";
+  }
+
+  if (body.model.includes("mistral")) {
+    return "mistral-ai";
+  }
+
+  if (body.model.includes("claude")) {
+    return body.messages?.length ? "anthropic-chat" : "anthropic-text";
+  }
+
+  if (body.model.includes("gemini")) {
+    return "google-ai";
+  }
+
+  return "unknown";
+}
+
+export function sendErrorToClient({
+  options,
+  req,
+  res,
+}: {
+  options: ErrorGeneratorOptions;
+  req: express.Request;
+  res: express.Response;
+}) {
+  const { format: inputFormat } = options;
+
+  // This is an error thrown before we know the format of the request, so we
+  // can't send a response in the format the client expects.
+  const format =
+    inputFormat === "unknown" ? tryInferFormat(req.body) : inputFormat;
+  if (format === "unknown") {
+    return res.status(options.statusCode || 400).json({
+      error: options.message,
+      details: options.obj,
+    });
+  }
+
+  const completion = buildSpoofedCompletion({ ...options, format });
+  const event = buildSpoofedSSE({ ...options, format });
+  const isStreaming =
+    req.isStreaming || req.body.stream === true || req.body.stream === "true";
+
+  if (isStreaming) {
+    if (!res.headersSent) {
+      initializeSseStream(res);
+    }
+    res.write(event);
+    res.write(`data: [DONE]\n\n`);
+    res.end();
+  } else {
+    res.status(200).json(completion);
+  }
+}
+
+/**
+ * Returns a non-streaming completion object that looks like it came from the
+ * service that the request is being proxied to. Used to send error messages to
+ * the client and have them look like normal responses, for clients with poor
+ * error handling.
+ */
+export function buildSpoofedCompletion({
+  format,
+  title,
+  message,
+  obj,
+  reqId,
+  model = "unknown",
+}: ErrorGeneratorOptions & { format: Exclude<APIFormat, "unknown"> }) {
+  const id = String(reqId);
+  const content = getMessageContent({ title, message, obj });
+
+  switch (format) {
+    case "openai":
+    case "mistral-ai":
+      return {
+        id: "error-" + id,
+        object: "chat.completion",
+        created: Date.now(),
+        model,
+        usage: { prompt_tokens: 0, completion_tokens: 0, total_tokens: 0 },
+        choices: [
+          {
+            message: { role: "assistant", content },
+            finish_reason: title,
+            index: 0,
+          },
+        ],
+      };
+    case "openai-text":
+      return {
+        id: "error-" + id,
+        object: "text_completion",
+        created: Date.now(),
+        model,
+        usage: { prompt_tokens: 0, completion_tokens: 0, total_tokens: 0 },
+        choices: [
+          { text: content, index: 0, logprobs: null, finish_reason: title },
+        ],
+      };
+    case "anthropic-text":
+      return {
+        id: "error-" + id,
+        type: "completion",
+        completion: content,
+        stop_reason: title,
+        stop: null,
+        model,
+      };
+    case "anthropic-chat":
+      return {
+        id: "error-" + id,
+        type: "message",
+        role: "assistant",
+        content: [{ type: "text", text: content }],
+        model,
+        stop_reason: title,
+        stop_sequence: null,
+      };
+    case "google-ai":
+      // TODO: Native Google AI non-streaming responses are not supported, this
+      // is an untested guess at what the response should look like.
+      return {
+        id: "error-" + id,
+        object: "chat.completion",
+        created: Date.now(),
+        model,
+        candidates: [
+          {
+            content: { parts: [{ text: content }], role: "model" },
+            finishReason: title,
+            index: 0,
+            tokenCount: null,
+            safetyRatings: [],
+          },
+        ],
+      };
+    case "openai-image":
+      return obj;
+    default:
+      assertNever(format);
+  }
+}
+
+/**
+ * Returns an SSE message that looks like a completion event for the service
+ * that the request is being proxied to. Used to send error messages to the
+ * client in the middle of a streaming request.
+ */
+export function buildSpoofedSSE({
+  format,
+  title,
+  message,
+  obj,
+  reqId,
+  model = "unknown",
+}: ErrorGeneratorOptions & { format: Exclude<APIFormat, "unknown"> }) {
+  const id = String(reqId);
+  const content = getMessageContent({ title, message, obj });
+
+  let event;
+
+  switch (format) {
+    case "openai":
+    case "mistral-ai":
+      event = {
+        id: "chatcmpl-" + id,
+        object: "chat.completion.chunk",
+        created: Date.now(),
+        model,
+        choices: [{ delta: { content }, index: 0, finish_reason: title }],
+      };
+      break;
+    case "openai-text":
+      event = {
+        id: "cmpl-" + id,
+        object: "text_completion",
+        created: Date.now(),
+        choices: [
+          { text: content, index: 0, logprobs: null, finish_reason: title },
+        ],
+        model,
+      };
+      break;
+    case "anthropic-text":
+      event = {
+        completion: content,
+        stop_reason: title,
+        truncated: false,
+        stop: null,
+        model,
+        log_id: "proxy-req-" + id,
+      };
+      break;
+    case "anthropic-chat":
+      event = {
+        type: "content_block_delta",
+        index: 0,
+        delta: { type: "text_delta", text: content },
+      };
+      break;
+    case "google-ai":
+      return JSON.stringify({
+        candidates: [
+          {
+            content: { parts: [{ text: content }], role: "model" },
+            finishReason: title,
+            index: 0,
+            tokenCount: null,
+            safetyRatings: [],
+          },
+        ],
+      });
+    case "openai-image":
+      return JSON.stringify(obj);
+    default:
+      assertNever(format);
+  }
+
+  if (format === "anthropic-text") {
+    return (
+      ["event: completion", `data: ${JSON.stringify(event)}`].join("\n") +
+      "\n\n"
+    );
+  }
+
+  // ugh.
+  if (format === "anthropic-chat") {
+    return (
+      [
+        [
+          "event: message_start",
+          `data: ${JSON.stringify({
+            type: "message_start",
+            message: {
+              id: "error-" + id,
+              type: "message",
+              role: "assistant",
+              content: [],
+              model,
+            },
+          })}`,
+        ].join("\n"),
+        [
+          "event: content_block_start",
+          `data: ${JSON.stringify({
+            type: "content_block_start",
+            index: 0,
+            content_block: { type: "text", text: "" },
+          })}`,
+        ].join("\n"),
+        ["event: content_block_delta", `data: ${JSON.stringify(event)}`].join(
+          "\n"
+        ),
+        [
+          "event: content_block_stop",
+          `data: ${JSON.stringify({ type: "content_block_stop", index: 0 })}`,
+        ].join("\n"),
+        [
+          "event: message_delta",
+          `data: ${JSON.stringify({
+            type: "message_delta",
+            delta: { stop_reason: title, stop_sequence: null, usage: null },
+          })}`,
+        ],
+        [
+          "event: message_stop",
+          `data: ${JSON.stringify({ type: "message_stop" })}`,
+        ].join("\n"),
+      ].join("\n\n") + "\n\n"
+    );
+  }
+
+  return `data: ${JSON.stringify(event)}\n\n`;
+}

src/proxy/middleware/response/handle-streamed-response.ts

@@ -1,410 +1,181 @@
-import { Request, Response } from "express";
+import express from "express";
-import * as http from "http";
+import { pipeline, Readable, Transform } from "stream";
-import { buildFakeSseMessage } from "../common";
+import StreamArray from "stream-json/streamers/StreamArray";
-import { RawResponseBodyHandler, decodeResponseBody } from ".";
+import { StringDecoder } from "string_decoder";
-import { assertNever } from "../../../shared/utils";
+import { promisify } from "util";
+import { APIFormat, keyPool } from "../../../shared/key-management";
+import {
+  copySseResponseHeaders,
+  initializeSseStream,
+} from "../../../shared/streaming";
+import type { logger } from "../../../logger";
+import { enqueue } from "../../queue";
+import { decodeResponseBody, RawResponseBodyHandler, RetryableError } from ".";
+import { getAwsEventStreamDecoder } from "./streaming/aws-event-stream-decoder";
+import { EventAggregator } from "./streaming/event-aggregator";
+import { SSEMessageTransformer } from "./streaming/sse-message-transformer";
+import { SSEStreamAdapter } from "./streaming/sse-stream-adapter";
+import { buildSpoofedSSE, sendErrorToClient } from "./error-generator";
+import { BadRequestError } from "../../../shared/errors";
 
-type OpenAiChatCompletionResponse = {
+const pipelineAsync = promisify(pipeline);
-  id: string;
-  object: string;
-  created: number;
-  model: string;
-  choices: {
-    message: { role: string; content: string };
-    finish_reason: string | null;
-    index: number;
-  }[];
-};
-
-type OpenAiTextCompletionResponse = {
-  id: string;
-  object: string;
-  created: number;
-  model: string;
-  choices: {
-    text: string;
-    finish_reason: string | null;
-    index: number;
-    logprobs: null;
-  }[];
-};
-
-type AnthropicCompletionResponse = {
-  completion: string;
-  stop_reason: string;
-  truncated: boolean;
-  stop: any;
-  model: string;
-  log_id: string;
-  exception: null;
-};
 
 /**
- * Consume the SSE stream and forward events to the client. Once the stream is
+ * `handleStreamedResponse` consumes and transforms a streamed response from the
- * stream is closed, resolve with the full response body so that subsequent
+ * upstream service, forwarding events to the client in their requested format.
- * middleware can work with it.
+ * After the entire stream has been consumed, it resolves with the full response
+ * body so that subsequent middleware in the chain can process it as if it were
+ * a non-streaming response.
  *
- * Typically we would only need of the raw response handlers to execute, but
+ * In the event of an error, the request's streaming flag is unset and the non-
- * in the event a streamed request results in a non-200 response, we need to
+ * streaming response handler is called instead.
- * fall back to the non-streaming response handler so that the error handler
- * can inspect the error response.
  *
- * Currently most frontends don't support Anthropic streaming, so users can opt
+ * If the error is retryable, that handler will re-enqueue the request and also
- * to send requests for Claude models via an endpoint that accepts OpenAI-
+ * reset the streaming flag. Unfortunately the streaming flag is set and unset
- * compatible requests and translates the received Anthropic SSE events into
+ * in multiple places, so it's hard to keep track of.
- * OpenAI ones, essentially pretending to be an OpenAI streaming API.
  */
 export const handleStreamedResponse: RawResponseBodyHandler = async (
   proxyRes,
   req,
   res
 ) => {
-  // If these differ, the user is using the OpenAI-compatibile endpoint, so
+  const { hash } = req.key!;
-  // we need to translate the SSE events into OpenAI completion events for their
-  // frontend.
   if (!req.isStreaming) {
-    const err = new Error(
+    throw new Error("handleStreamedResponse called for non-streaming request.");
-      "handleStreamedResponse called for non-streaming request."
-    );
-    req.log.error({ stack: err.stack, api: req.inboundApi }, err.message);
-    throw err;
   }
 
-  const key = req.key!;
+  if (proxyRes.statusCode! > 201) {
-  if (proxyRes.statusCode !== 200) {
-    // Ensure we use the non-streaming middleware stack since we won't be
-    // getting any events.
     req.isStreaming = false;
     req.log.warn(
-      { statusCode: proxyRes.statusCode, key: key.hash },
+      { statusCode: proxyRes.statusCode, key: hash },
       `Streaming request returned error status code. Falling back to non-streaming response handler.`
     );
     return decodeResponseBody(proxyRes, req, res);
   }
 
-  return new Promise((resolve, reject) => {
+  req.log.debug({ headers: proxyRes.headers }, `Starting to proxy SSE stream.`);
-    req.log.info({ key: key.hash }, `Starting to proxy SSE stream.`);
 
-    // Queued streaming requests will already have a connection open and headers
+  // Typically, streaming will have already been initialized by the request
-    // sent due to the heartbeat handler.  In that case we can just start
+  // queue to send heartbeat pings.
-    // streaming the response without sending headers.
+  if (!res.headersSent) {
-    if (!res.headersSent) {
+    copySseResponseHeaders(proxyRes, res);
-      res.setHeader("Content-Type", "text/event-stream");
+    initializeSseStream(res);
-      res.setHeader("Cache-Control", "no-cache");
+  }
-      res.setHeader("Connection", "keep-alive");
-      res.setHeader("X-Accel-Buffering", "no");
-      copyHeaders(proxyRes, res);
-      res.flushHeaders();
-    }
 
-    const originalEvents: string[] = [];
+  const prefersNativeEvents = req.inboundApi === req.outboundApi;
-    let partialMessage = "";
+  const streamOptions = {
-    let lastPosition = 0;
+    contentType: proxyRes.headers["content-type"],
-    let eventCount = 0;
+    api: req.outboundApi,
+    logger: req.log,
+  };
 
-    type ProxyResHandler<T extends unknown> = (...args: T[]) => void;
+  // Decoder turns the raw response stream into a stream of events in some
-    function withErrorHandling<T extends unknown>(fn: ProxyResHandler<T>) {
+  // format (text/event-stream, vnd.amazon.event-stream, streaming JSON, etc).
-      return (...args: T[]) => {
+  const decoder = getDecoder({ ...streamOptions, input: proxyRes });
-        try {
+  // Adapter transforms the decoded events into server-sent events.
-          fn(...args);
+  const adapter = new SSEStreamAdapter(streamOptions);
-        } catch (error) {
+  // Aggregator compiles all events into a single response object.
-          proxyRes.emit("error", error);
+  const aggregator = new EventAggregator({ format: req.outboundApi });
-        }
+  // Transformer converts server-sent events from one vendor's API message
-      };
+  // format to another.
-    }
+  const transformer = new SSEMessageTransformer({
-
+    inputFormat: req.outboundApi, // The format of the upstream service's events
-    proxyRes.on(
+    outputFormat: req.inboundApi, // The format the client requested
-      "data",
+    inputApiVersion: String(req.headers["anthropic-version"]),
-      withErrorHandling((chunk: Buffer) => {
+    logger: req.log,
-        // We may receive multiple (or partial) SSE messages in a single chunk,
+    requestId: String(req.id),
-        // so we need to buffer and emit seperate stream events for full
+    requestedModel: req.body.model,
-        // messages so we can parse/transform them properly.
+  })
-        const str = chunk.toString();
+    .on("originalMessage", (msg: string) => {
-
+      if (prefersNativeEvents) res.write(msg);
-        // Anthropic uses CRLF line endings (out-of-spec btw)
+    })
-        const fullMessages = (partialMessage + str).split(/\r?\n\r?\n/);
+    .on("data", (msg) => {
-        partialMessage = fullMessages.pop() || "";
+      if (!prefersNativeEvents) res.write(`data: ${JSON.stringify(msg)}\n\n`);
-
+      aggregator.addEvent(msg);
-        for (const message of fullMessages) {
-          proxyRes.emit("full-sse-event", message);
-        }
-      })
-    );
-
-    proxyRes.on(
-      "full-sse-event",
-      withErrorHandling((data) => {
-        originalEvents.push(data);
-        const { event, position } = transformEvent({
-          data,
-          requestApi: req.inboundApi,
-          responseApi: req.outboundApi,
-          lastPosition,
-          index: eventCount++,
-        });
-        lastPosition = position;
-        res.write(event + "\n\n");
-      })
-    );
-
-    proxyRes.on(
-      "end",
-      withErrorHandling(() => {
-        let finalBody = convertEventsToFinalResponse(originalEvents, req);
-        req.log.info({ key: key.hash }, `Finished proxying SSE stream.`);
-        res.end();
-        resolve(finalBody);
-      })
-    );
-
-    proxyRes.on("error", (err) => {
-      req.log.error({ error: err, key: key.hash }, `Mid-stream error.`);
-      const fakeErrorEvent = buildFakeSseMessage(
-        "mid-stream-error",
-        err.message,
-        req
-      );
-      res.write(`data: ${JSON.stringify(fakeErrorEvent)}\n\n`);
-      res.write("data: [DONE]\n\n");
-      res.end();
-      reject(err);
     });
-  });
-};
 
-type SSETransformationArgs = {
+  try {
-  data: string;
+    await Promise.race([
-  requestApi: string;
+      handleAbortedStream(req, res),
-  responseApi: string;
+      pipelineAsync(proxyRes, decoder, adapter, transformer),
-  lastPosition: number;
+    ]);
-  index: number;
+    req.log.debug(`Finished proxying SSE stream.`);
-};
+    res.end();
-
+    return aggregator.getFinalResponse();
-/**
+  } catch (err) {
- * Transforms SSE events from the given response API into events compatible with
+    if (err instanceof RetryableError) {
- * the API requested by the client.
+      keyPool.markRateLimited(req.key!);
- */
+      req.log.warn(
-function transformEvent(params: SSETransformationArgs) {
+        { key: req.key!.hash, retryCount: req.retryCount },
-  const { data, requestApi, responseApi } = params;
+        `Re-enqueueing request due to retryable error during streaming response.`
-  if (requestApi === responseApi) {
-    return { position: -1, event: data };
-  }
-
-  const trans = `${requestApi}->${responseApi}`;
-  switch (trans) {
-    case "openai->openai-text":
-      return transformOpenAITextEventToOpenAIChat(params);
-    case "openai->anthropic":
-      // TODO: handle new anthropic streaming format
-      return transformV1AnthropicEventToOpenAI(params);
-    case "openai->google-palm":
-      return transformPalmEventToOpenAI(params);
-    default:
-      throw new Error(`Unsupported streaming API transformation. ${trans}`);
-  }
-}
-
-function transformOpenAITextEventToOpenAIChat(params: SSETransformationArgs) {
-  const { data, index } = params;
-
-  if (!data.startsWith("data:")) return { position: -1, event: data };
-  if (data.startsWith("data: [DONE]")) return { position: -1, event: data };
-
-  const event = JSON.parse(data.slice("data: ".length));
-
-  // The very first event must be a role assignment with no content.
-
-  const createEvent = () => ({
-    id: event.id,
-    object: "chat.completion.chunk",
-    created: event.created,
-    model: event.model,
-    choices: [
-      {
-        message: { role: "", content: "" } as {
-          role?: string;
-          content: string;
-        },
-        index: 0,
-        finish_reason: null,
-      },
-    ],
-  });
-
-  let buffer = "";
-
-  if (index === 0) {
-    const initialEvent = createEvent();
-    initialEvent.choices[0].message.role = "assistant";
-    buffer = `data: ${JSON.stringify(initialEvent)}\n\n`;
-  }
-
-  const newEvent = {
-    ...event,
-    choices: [
-      {
-        ...event.choices[0],
-        delta: { content: event.choices[0].text },
-        text: undefined,
-      },
-    ],
-  };
-
-  buffer += `data: ${JSON.stringify(newEvent)}`;
-
-  return { position: -1, event: buffer };
-}
-
-function transformV1AnthropicEventToOpenAI(params: SSETransformationArgs) {
-  const { data, lastPosition } = params;
-  // Anthropic sends the full completion so far with each event whereas OpenAI
-  // only sends the delta. To make the SSE events compatible, we remove
-  // everything before `lastPosition` from the completion.
-  if (!data.startsWith("data:")) {
-    return { position: lastPosition, event: data };
-  }
-
-  if (data.startsWith("data: [DONE]")) {
-    return { position: lastPosition, event: data };
-  }
-
-  const event = JSON.parse(data.slice("data: ".length));
-  const newEvent = {
-    id: "ant-" + event.log_id,
-    object: "chat.completion.chunk",
-    created: Date.now(),
-    model: event.model,
-    choices: [
-      {
-        index: 0,
-        delta: { content: event.completion?.slice(lastPosition) },
-        finish_reason: event.stop_reason,
-      },
-    ],
-  };
-  return {
-    position: event.completion.length,
-    event: `data: ${JSON.stringify(newEvent)}`,
-  };
-}
-
-function transformPalmEventToOpenAI({ data }: SSETransformationArgs) {
-  throw new Error("PaLM streaming not yet supported.");
-  return { position: -1, event: data };
-}
-
-/** Copy headers, excluding ones we're already setting for the SSE response. */
-function copyHeaders(proxyRes: http.IncomingMessage, res: Response) {
-  const toOmit = [
-    "content-length",
-    "content-encoding",
-    "transfer-encoding",
-    "content-type",
-    "connection",
-    "cache-control",
-  ];
-  for (const [key, value] of Object.entries(proxyRes.headers)) {
-    if (!toOmit.includes(key) && value) {
-      res.setHeader(key, value);
-    }
-  }
-}
-
-/**
- * Converts the list of incremental SSE events into an object that resembles a
- * full, non-streamed response from the API so that subsequent middleware can
- * operate on it as if it were a normal response.
- * Events are expected to be in the format they were received from the API.
- */
-function convertEventsToFinalResponse(events: string[], req: Request) {
-  switch (req.outboundApi) {
-    case "openai": {
-      let merged: OpenAiChatCompletionResponse = {
-        id: "",
-        object: "",
-        created: 0,
-        model: "",
-        choices: [],
-      };
-      merged = events.reduce((acc, event, i) => {
-        if (!event.startsWith("data: ")) return acc;
-        if (event === "data: [DONE]") return acc;
-
-        const data = JSON.parse(event.slice("data: ".length));
-
-        // The first chat chunk only contains the role assignment and metadata
-        if (i === 0) {
-          return {
-            id: data.id,
-            object: data.object,
-            created: data.created,
-            model: data.model,
-            choices: [
-              {
-                message: { role: data.choices[0].delta.role, content: "" },
-                index: 0,
-                finish_reason: null,
-              },
-            ],
-          };
-        }
-
-        if (data.choices[0].delta.content) {
-          acc.choices[0].message.content += data.choices[0].delta.content;
-        }
-        acc.choices[0].finish_reason = data.choices[0].finish_reason;
-        return acc;
-      }, merged);
-      return merged;
-    }
-    case "openai-text": {
-      let merged: OpenAiTextCompletionResponse = {
-        id: "",
-        object: "",
-        created: 0,
-        model: "",
-        choices: [],
-        // TODO: merge logprobs
-      };
-      merged = events.reduce((acc, event, i) => {
-        if (!event.startsWith("data: ")) return acc;
-        if (event === "data: [DONE]") return acc;
-
-        const data = JSON.parse(event.slice("data: ".length));
-
-        return {
-          id: data.id,
-          object: data.object,
-          created: data.created,
-          model: data.model,
-          choices: [
-            {
-              text: acc.choices[0]?.text + data.choices[0].text,
-              index: 0,
-              finish_reason: data.choices[0].finish_reason,
-              logprobs: null,
-            },
-          ],
-        };
-      }, merged);
-      return merged;
-    }
-    case "anthropic": {
-      /*
-       * Full complete responses from Anthropic are conveniently just the same as
-       * the final SSE event before the "DONE" event, so we can reuse that
-       */
-      const lastEvent = events[events.length - 2].toString();
-      const data = JSON.parse(
-        lastEvent.slice(lastEvent.indexOf("data: ") + "data: ".length)
       );
-      const final: AnthropicCompletionResponse = { ...data, log_id: req.id };
+      req.retryCount++;
-      return final;
+      await enqueue(req);
+    } else if (err instanceof BadRequestError) {
+      sendErrorToClient({
+        req,
+        res,
+        options: {
+          format: req.inboundApi,
+          title: "Proxy streaming error (Bad Request)",
+          message: `The API returned an error while streaming your request. Your prompt might not be formatted correctly.\n\n*${err.message}*`,
+          reqId: req.id,
+          model: req.body?.model,
+        },
+      });
+    } else {
+      const { message, stack, lastEvent } = err;
+      const eventText = JSON.stringify(lastEvent, null, 2) ?? "undefined";
+      const errorEvent = buildSpoofedSSE({
+        format: req.inboundApi,
+        title: "Proxy stream error",
+        message: "An unexpected error occurred while streaming the response.",
+        obj: { message, stack, lastEvent: eventText },
+        reqId: req.id,
+        model: req.body?.model,
+      });
+      res.write(errorEvent);
+      res.write(`data: [DONE]\n\n`);
+      res.end();
     }
-    case "google-palm": {
+    throw err;
-      throw new Error("PaLM streaming not yet supported.");
+  }
-    }
+};
-    default:
+
-      assertNever(req.outboundApi);
+function handleAbortedStream(req: express.Request, res: express.Response) {
+  return new Promise<void>((resolve) =>
+    res.on("close", () => {
+      if (!res.writableEnded) {
+        req.log.info("Client prematurely closed connection during stream.");
+      }
+      resolve();
+    })
+  );
+}
+
+function getDecoder(options: {
+  input: Readable;
+  api: APIFormat;
+  logger: typeof logger;
+  contentType?: string;
+}) {
+  const { api, contentType, input, logger } = options;
+  if (contentType?.includes("application/vnd.amazon.eventstream")) {
+    return getAwsEventStreamDecoder({ input, logger });
+  } else if (api === "google-ai") {
+    return StreamArray.withParser();
+  } else {
+    // Passthrough stream, but ensures split chunks across multi-byte characters
+    // are handled correctly.
+    const stringDecoder = new StringDecoder("utf8");
+    return new Transform({
+      readableObjectMode: true,
+      writableObjectMode: false,
+      transform(chunk, _encoding, callback) {
+        const text = stringDecoder.write(chunk);
+        if (text) this.push(text);
+        callback();
+      },
+    });
   }
 }

src/proxy/middleware/response/index.ts

@@ -3,23 +3,27 @@ import { Request, Response } from "express";
 import * as http from "http";
 import util from "util";
 import zlib from "zlib";
-import { logger } from "../../../logger";
+import { enqueue, trackWaitTime } from "../../queue";
+import { HttpError } from "../../../shared/errors";
 import { keyPool } from "../../../shared/key-management";
 import { getOpenAIModelFamily } from "../../../shared/models";
-import { enqueue, trackWaitTime } from "../../queue";
+import { countTokens } from "../../../shared/tokenization";
 import {
   incrementPromptCount,
   incrementTokenCount,
 } from "../../../shared/users/user-store";
+import { assertNever } from "../../../shared/utils";
+import { refundLastAttempt } from "../../rate-limit";
 import {
-  getCompletionForService,
+  getCompletionFromBody,
-  isCompletionRequest,
+  isImageGenerationRequest,
-  writeErrorResponse,
+  isTextGenerationRequest,
+  sendProxyError,
 } from "../common";
 import { handleStreamedResponse } from "./handle-streamed-response";
 import { logPrompt } from "./log-prompt";
-import { countTokens } from "../../../shared/tokenization";
+import { saveImage } from "./save-image";
-import { assertNever } from "../../../shared/utils";
+import { config } from "../../../config";
 
 const DECODER_MAP = {
   gzip: util.promisify(zlib.gunzip),
@@ -33,7 +37,7 @@ const isSupportedContentEncoding = (
   return contentEncoding in DECODER_MAP;
 };
 
-class RetryableError extends Error {
+export class RetryableError extends Error {
   constructor(message: string) {
     super(message);
     this.name = "RetryableError";
@@ -83,7 +87,7 @@ export const createOnProxyResHandler = (apiMiddleware: ProxyResMiddleware) => {
       ? handleStreamedResponse
       : decodeResponseBody;
 
-    let lastMiddlewareName = initialHandler.name;
+    let lastMiddleware = initialHandler.name;
 
     try {
       const body = await initialHandler(proxyRes, req, res);
@@ -102,58 +106,61 @@ export const createOnProxyResHandler = (apiMiddleware: ProxyResMiddleware) => {
       } else {
         middlewareStack.push(
           trackRateLimit,
+          addProxyInfo,
           handleUpstreamErrors,
           countResponseTokens,
           incrementUsage,
           copyHttpHeaders,
+          saveImage,
           logPrompt,
           ...apiMiddleware
         );
       }
 
       for (const middleware of middlewareStack) {
-        lastMiddlewareName = middleware.name;
+        lastMiddleware = middleware.name;
         await middleware(proxyRes, req, res, body);
       }
 
       trackWaitTime(req);
-    } catch (error: any) {
+    } catch (error) {
       // Hack: if the error is a retryable rate-limit error, the request has
       // been re-enqueued and we can just return without doing anything else.
       if (error instanceof RetryableError) {
         return;
       }
 
-      const errorData = {
+      // Already logged and responded to the client by handleUpstreamErrors
-        error: error.stack,
+      if (error instanceof HttpError) {
-        thrownBy: lastMiddlewareName,
+        if (!res.writableEnded) res.end();
-        key: req.key?.hash,
-      };
-      const message = `Error while executing proxy response middleware: ${lastMiddlewareName} (${error.message})`;
-      if (res.headersSent) {
-        req.log.error(errorData, message);
-        // This should have already been handled by the error handler, but
-        // just in case...
-        if (!res.writableEnded) {
-          res.end();
-        }
         return;
       }
-      logger.error(errorData, message);
+
-      res
+      const { stack, message } = error;
-        .status(500)
+      const info = { stack, lastMiddleware, key: req.key?.hash };
-        .json({ error: "Internal server error", proxy_note: message });
+      const description = `Error while executing proxy response middleware: ${lastMiddleware} (${message})`;
+
+      if (res.headersSent) {
+        req.log.error(info, description);
+        if (!res.writableEnded) res.end();
+        return;
+      } else {
+        req.log.error(info, description);
+        res
+          .status(500)
+          .json({ error: "Internal server error", proxy_note: description });
+      }
     }
   };
 };
 
-function reenqueueRequest(req: Request) {
+async function reenqueueRequest(req: Request) {
   req.log.info(
     { key: req.key?.hash, retryCount: req.retryCount },
     `Re-enqueueing request due to retryable error`
   );
   req.retryCount++;
-  enqueue(req);
+  await enqueue(req);
 }
 
 /**
@@ -173,7 +180,7 @@ export const decodeResponseBody: RawResponseBodyHandler = async (
     throw err;
   }
 
-  const promise = new Promise<string>((resolve, reject) => {
+  return new Promise<string>((resolve, reject) => {
     let chunks: Buffer[] = [];
     proxyRes.on("data", (chunk) => chunks.push(chunk));
     proxyRes.on("end", async () => {
@@ -183,15 +190,17 @@ export const decodeResponseBody: RawResponseBodyHandler = async (
       if (contentEncoding) {
         if (isSupportedContentEncoding(contentEncoding)) {
           const decoder = DECODER_MAP[contentEncoding];
+          // @ts-ignore - started failing after upgrading TypeScript, don't care
+          // as it was never a problem.
           body = await decoder(body);
         } else {
-          const errorMessage = `Proxy received response with unsupported content-encoding: ${contentEncoding}`;
+          const error = `Proxy received response with unsupported content-encoding: ${contentEncoding}`;
-          logger.warn({ contentEncoding, key: req.key?.hash }, errorMessage);
+          req.log.warn({ contentEncoding, key: req.key?.hash }, error);
-          writeErrorResponse(req, res, 500, {
+          sendProxyError(req, res, 500, "Internal Server Error", {
-            error: errorMessage,
+            error,
             contentEncoding,
           });
-          return reject(errorMessage);
+          return reject(error);
         }
       }
 
@@ -201,25 +210,29 @@ export const decodeResponseBody: RawResponseBodyHandler = async (
           return resolve(json);
         }
         return resolve(body.toString());
-      } catch (error: any) {
+      } catch (e) {
-        const errorMessage = `Proxy received response with invalid JSON: ${error.message}`;
+        const msg = `Proxy received response with invalid JSON: ${e.message}`;
-        logger.warn({ error, key: req.key?.hash }, errorMessage);
+        req.log.warn({ error: e.stack, key: req.key?.hash }, msg);
-        writeErrorResponse(req, res, 500, { error: errorMessage });
+        sendProxyError(req, res, 500, "Internal Server Error", { error: msg });
-        return reject(errorMessage);
+        return reject(msg);
       }
     });
   });
-  return promise;
 };
 
-// TODO: This is too specific to OpenAI's error responses.
+type ProxiedErrorPayload = {
+  error?: Record<string, any>;
+  message?: string;
+  proxy_note?: string;
+};
+
 /**
  * Handles non-2xx responses from the upstream service.  If the proxied response
  * is an error, this will respond to the client with an error payload and throw
  * an error to stop the middleware stack.
  * On 429 errors, if request queueing is enabled, the request will be silently
  * re-enqueued.  Otherwise, the request will be rejected with an error payload.
- * @throws {Error} On HTTP error status code from upstream service
+ * @throws {HttpError} On HTTP error status code from upstream service
  */
 const handleUpstreamErrors: ProxyResHandlerWithBody = async (
   proxyRes,
@@ -228,90 +241,136 @@ const handleUpstreamErrors: ProxyResHandlerWithBody = async (
   body
 ) => {
   const statusCode = proxyRes.statusCode || 500;
+  const statusMessage = proxyRes.statusMessage || "Internal Server Error";
 
   if (statusCode < 400) {
     return;
   }
 
-  let errorPayload: Record<string, any>;
+  let errorPayload: ProxiedErrorPayload;
-  // Subtract 1 from available keys because if this message is being shown,
+  const tryAgainMessage = keyPool.available(req.body?.model)
-  // it's because the key is about to be disabled.
+    ? `There may be more keys available for this model; try again in a few seconds.`
-  const availableKeys = keyPool.available(req.outboundApi) - 1;
+    : "There are no more keys available for this model.";
-  const tryAgainMessage = Boolean(availableKeys)
-    ? `There are ${availableKeys} more keys available; try your request again.`
-    : "There are no more keys available.";
 
   try {
-    if (typeof body === "object") {
+    assertJsonResponse(body);
-      errorPayload = body;
+    errorPayload = body;
-    } else {
+  } catch (parseError) {
-      throw new Error("Received unparsable error response from upstream.");
+    // Likely Bad Gateway or Gateway Timeout from upstream's reverse proxy
-    }
+    const hash = req.key?.hash;
-  } catch (parseError: any) {
+    req.log.warn({ statusCode, statusMessage, key: hash }, parseError.message);
-    const statusMessage = proxyRes.statusMessage || "Unknown error";
-    // Likely Bad Gateway or Gateway Timeout from reverse proxy/load balancer
-    logger.warn(
-      { statusCode, statusMessage, key: req.key?.hash },
-      parseError.message
-    );
 
     const errorObject = {
-      statusCode,
-      statusMessage: proxyRes.statusMessage,
       error: parseError.message,
-      proxy_note: `This is likely a temporary error with the upstream service.`,
+      status: statusCode,
+      statusMessage,
+      proxy_note: `Proxy got back an error, but it was not in JSON format. This is likely a temporary problem with the upstream service.`,
     };
-    writeErrorResponse(req, res, statusCode, errorObject);
+
-    throw new Error(parseError.message);
+    sendProxyError(req, res, statusCode, statusMessage, errorObject);
+    throw new HttpError(statusCode, parseError.message);
   }
 
-  logger.warn(
+  const errorType =
-    {
+    errorPayload.error?.code ||
-      statusCode,
+    errorPayload.error?.type ||
-      type: errorPayload.error?.code,
+    getAwsErrorType(proxyRes.headers["x-amzn-errortype"]);
-      errorPayload,
+
-      key: req.key?.hash,
+  req.log.warn(
-    },
+    { statusCode, type: errorType, errorPayload, key: req.key?.hash },
     `Received error response from upstream. (${proxyRes.statusMessage})`
   );
 
+  const service = req.key!.service;
+  if (service === "aws") {
+    // Try to standardize the error format for AWS
+    errorPayload.error = { message: errorPayload.message, type: errorType };
+    delete errorPayload.message;
+  }
+
   if (statusCode === 400) {
-    // Bad request (likely prompt is too long)
+    // Bad request. For OpenAI, this is usually due to prompt length.
-    switch (req.outboundApi) {
+    // For Anthropic, this is usually due to missing preamble.
+    switch (service) {
       case "openai":
-      case "openai-text":
+      case "google-ai":
-      case "google-palm":
+      case "mistral-ai":
-        errorPayload.proxy_note = `Upstream service rejected the request as invalid. Your prompt may be too long for ${req.body?.model}.`;
+      case "azure":
+        const filteredCodes = ["content_policy_violation", "content_filter"];
+        if (filteredCodes.includes(errorPayload.error?.code)) {
+          errorPayload.proxy_note = `Request was filtered by the upstream API's content moderation system. Modify your prompt and try again.`;
+          refundLastAttempt(req);
+        } else if (errorPayload.error?.code === "billing_hard_limit_reached") {
+          // For some reason, some models return this 400 error instead of the
+          // same 429 billing error that other models return.
+          await handleOpenAIRateLimitError(req, tryAgainMessage, errorPayload);
+        } else {
+          errorPayload.proxy_note = `The upstream API rejected the request. Your prompt may be too long for ${req.body?.model}.`;
+        }
         break;
       case "anthropic":
-        maybeHandleMissingPreambleError(req, errorPayload);
+      case "aws":
+        await handleAnthropicBadRequestError(req, errorPayload);
         break;
       default:
-        assertNever(req.outboundApi);
+        assertNever(service);
     }
   } else if (statusCode === 401) {
     // Key is invalid or was revoked
     keyPool.disable(req.key!, "revoked");
     errorPayload.proxy_note = `API key is invalid or revoked. ${tryAgainMessage}`;
+  } else if (statusCode === 403) {
+    if (service === "anthropic") {
+      keyPool.disable(req.key!, "revoked");
+      errorPayload.proxy_note = `API key is invalid or revoked. ${tryAgainMessage}`;
+      return;
+    }
+    switch (errorType) {
+      case "UnrecognizedClientException":
+        // Key is invalid.
+        keyPool.disable(req.key!, "revoked");
+        errorPayload.proxy_note = `API key is invalid or revoked. ${tryAgainMessage}`;
+        break;
+      case "AccessDeniedException":
+        const isModelAccessError =
+          errorPayload.error?.message?.includes(`specified model ID`);
+        if (!isModelAccessError) {
+          req.log.error(
+            { key: req.key?.hash, model: req.body?.model },
+            "Disabling key due to AccessDeniedException when invoking model. If credentials are valid, check IAM permissions."
+          );
+          keyPool.disable(req.key!, "revoked");
+        }
+        errorPayload.proxy_note = `API key doesn't have access to the requested resource. Model ID: ${req.body?.model}`;
+        break;
+      default:
+        errorPayload.proxy_note = `Received 403 error. Key may be invalid.`;
+    }
   } else if (statusCode === 429) {
-    switch (req.outboundApi) {
+    switch (service) {
       case "openai":
-      case "openai-text":
+        await handleOpenAIRateLimitError(req, tryAgainMessage, errorPayload);
-        handleOpenAIRateLimitError(req, tryAgainMessage, errorPayload);
         break;
       case "anthropic":
-        handleAnthropicRateLimitError(req, errorPayload);
+        await handleAnthropicRateLimitError(req, errorPayload);
+        break;
+      case "aws":
+        await handleAwsRateLimitError(req, errorPayload);
+        break;
+      case "azure":
+      case "mistral-ai":
+        await handleAzureRateLimitError(req, errorPayload);
+        break;
+      case "google-ai":
+        await handleGoogleAIRateLimitError(req, errorPayload);
         break;
-      case "google-palm":
-        throw new Error("Rate limit handling not implemented for PaLM");
       default:
-        assertNever(req.outboundApi);
+        assertNever(service);
     }
   } else if (statusCode === 404) {
     // Most likely model not found
-    switch (req.outboundApi) {
+    switch (service) {
       case "openai":
-      case "openai-text":
         if (errorPayload.error?.code === "model_not_found") {
           const requestedModel = req.body.model;
           const modelFamily = getOpenAIModelFamily(requestedModel);
@@ -325,11 +384,20 @@ const handleUpstreamErrors: ProxyResHandlerWithBody = async (
       case "anthropic":
         errorPayload.proxy_note = `The requested Claude model might not exist, or the key might not be provisioned for it.`;
         break;
-      case "google-palm":
+      case "google-ai":
-        errorPayload.proxy_note = `The requested Google PaLM model might not exist, or the key might not be provisioned for it.`;
+        errorPayload.proxy_note = `The requested Google AI model might not exist, or the key might not be provisioned for it.`;
+        break;
+      case "mistral-ai":
+        errorPayload.proxy_note = `The requested Mistral AI model might not exist, or the key might not be provisioned for it.`;
+        break;
+      case "aws":
+        errorPayload.proxy_note = `The requested AWS resource might not exist, or the key might not have access to it.`;
+        break;
+      case "azure":
+        errorPayload.proxy_note = `The assigned Azure deployment does not support the requested model.`;
         break;
       default:
-        assertNever(req.outboundApi);
+        assertNever(service);
     }
   } else {
     errorPayload.proxy_note = `Unrecognized error from upstream service.`;
@@ -343,103 +411,234 @@ const handleUpstreamErrors: ProxyResHandlerWithBody = async (
     );
   }
 
-  writeErrorResponse(req, res, statusCode, errorPayload);
+  sendProxyError(req, res, statusCode, statusMessage, errorPayload);
-  throw new Error(errorPayload.error?.message);
+  // This is bubbled up to onProxyRes's handler for logging but will not trigger
+  // a write to the response as `sendProxyError` has just done that.
+  throw new HttpError(statusCode, errorPayload.error?.message);
 };
 
-/**
+async function handleAnthropicBadRequestError(
- * This is a workaround for a very strange issue where certain API keys seem to
- * enforce more strict input validation than others -- specifically, they will
- * require a `\n\nHuman:` prefix on the prompt, perhaps to prevent the key from
- * being used as a generic text completion service and to enforce the use of
- * the chat RLHF.  This is not documented anywhere, and it's not clear why some
- * keys enforce this and others don't.
- * This middleware checks for that specific error and marks the key as being
- * one that requires the prefix, and then re-enqueues the request.
- * The exact error is:
- * ```
- * {
- *   "error": {
- *     "type": "invalid_request_error",
- *     "message": "prompt must start with \"\n\nHuman:\" turn"
- *   }
- * }
- * ```
- */
-function maybeHandleMissingPreambleError(
   req: Request,
-  errorPayload: Record<string, any>
+  errorPayload: ProxiedErrorPayload
 ) {
-  if (
+  const { error } = errorPayload;
-    errorPayload.error?.type === "invalid_request_error" &&
+  const isMissingPreamble = error?.message.startsWith(
-    errorPayload.error?.message === 'prompt must start with "\n\nHuman:" turn'
+    `prompt must start with "\n\nHuman:" turn`
-  ) {
+  );
+
+  // Some keys mandate a \n\nHuman: preamble, which we can add and retry
+  if (isMissingPreamble) {
     req.log.warn(
       { key: req.key?.hash },
       "Request failed due to missing preamble. Key will be marked as such for subsequent requests."
     );
     keyPool.update(req.key!, { requiresPreamble: true });
-    reenqueueRequest(req);
+    await reenqueueRequest(req);
     throw new RetryableError("Claude request re-enqueued to add preamble.");
-  } else {
-    errorPayload.proxy_note = `Proxy received unrecognized error from Anthropic. Check the specific error for more information.`;
   }
+
+  // {"type":"error","error":{"type":"invalid_request_error","message":"Usage blocked until 2024-03-01T00:00:00+00:00 due to user specified spend limits."}}
+  // {"type":"error","error":{"type":"invalid_request_error","message":"Your credit balance is too low to access the Claude API. Please go to Plans & Billing to upgrade or purchase credits."}}
+  const isOverQuota =
+    error?.message?.match(/usage blocked until/i) ||
+    error?.message?.match(/credit balance is too low/i);
+  if (isOverQuota) {
+    req.log.warn(
+      { key: req.key?.hash, message: error?.message },
+      "Anthropic key has hit spending limit and will be disabled."
+    );
+    keyPool.disable(req.key!, "quota");
+    errorPayload.proxy_note = `Assigned key has hit its spending limit. ${error?.message}`;
+    return;
+  }
+
+  const isDisabled = error?.message?.match(/organization has been disabled/i);
+  if (isDisabled) {
+    req.log.warn(
+      { key: req.key?.hash, message: error?.message },
+      "Anthropic key has been disabled."
+    );
+    keyPool.disable(req.key!, "revoked");
+    errorPayload.proxy_note = `Assigned key has been disabled. ${error?.message}`;
+    return;
+  }
+
+  errorPayload.proxy_note = `Unrecognized error from the API. (${error?.message})`;
 }
 
-function handleAnthropicRateLimitError(
+async function handleAnthropicRateLimitError(
   req: Request,
-  errorPayload: Record<string, any>
+  errorPayload: ProxiedErrorPayload
 ) {
   if (errorPayload.error?.type === "rate_limit_error") {
     keyPool.markRateLimited(req.key!);
-    reenqueueRequest(req);
+    await reenqueueRequest(req);
     throw new RetryableError("Claude rate-limited request re-enqueued.");
   } else {
-    errorPayload.proxy_note = `Unrecognized rate limit error from Anthropic. Key may be over quota.`;
+    errorPayload.proxy_note = `Unrecognized 429 Too Many Requests error from the API.`;
   }
 }
 
-function handleOpenAIRateLimitError(
+async function handleAwsRateLimitError(
+  req: Request,
+  errorPayload: ProxiedErrorPayload
+) {
+  const errorType = errorPayload.error?.type;
+  switch (errorType) {
+    case "ThrottlingException":
+      keyPool.markRateLimited(req.key!);
+      await reenqueueRequest(req);
+      throw new RetryableError("AWS rate-limited request re-enqueued.");
+    case "ModelNotReadyException":
+      errorPayload.proxy_note = `The requested model is overloaded. Try again in a few seconds.`;
+      break;
+    default:
+      errorPayload.proxy_note = `Unrecognized rate limit error from AWS. (${errorType})`;
+  }
+}
+
+async function handleOpenAIRateLimitError(
   req: Request,
   tryAgainMessage: string,
-  errorPayload: Record<string, any>
+  errorPayload: ProxiedErrorPayload
-): Record<string, any> {
+): Promise<Record<string, any>> {
   const type = errorPayload.error?.type;
-  if (type === "insufficient_quota") {
+  switch (type) {
-    // Billing quota exceeded (key is dead, disable it)
+    case "insufficient_quota":
-    keyPool.disable(req.key!, "quota");
+    case "invalid_request_error": // this is the billing_hard_limit_reached error seen in some cases
-    errorPayload.proxy_note = `Assigned key's quota has been exceeded. ${tryAgainMessage}`;
+      // Billing quota exceeded (key is dead, disable it)
-  } else if (type === "access_terminated") {
+      keyPool.disable(req.key!, "quota");
-    // Account banned (key is dead, disable it)
+      errorPayload.proxy_note = `Assigned key's quota has been exceeded. ${tryAgainMessage}`;
-    keyPool.disable(req.key!, "revoked");
+      break;
-    errorPayload.proxy_note = `Assigned key has been banned by OpenAI for policy violations. ${tryAgainMessage}`;
+    case "access_terminated":
-  } else if (type === "billing_not_active") {
+      // Account banned (key is dead, disable it)
-    // Billing is not active (key is dead, disable it)
+      keyPool.disable(req.key!, "revoked");
-    keyPool.disable(req.key!, "revoked");
+      errorPayload.proxy_note = `Assigned key has been banned by OpenAI for policy violations. ${tryAgainMessage}`;
-    errorPayload.proxy_note = `Assigned key was deactivated by OpenAI. ${tryAgainMessage}`;
+      break;
-  } else if (type === "requests" || type === "tokens") {
+    case "billing_not_active":
-    // Per-minute request or token rate limit is exceeded, which we can retry
+      // Key valid but account billing is delinquent
-    keyPool.markRateLimited(req.key!);
+      keyPool.disable(req.key!, "quota");
-    // I'm aware this is confusing -- throwing this class of error will cause
+      errorPayload.proxy_note = `Assigned key has been disabled due to delinquent billing. ${tryAgainMessage}`;
-    // the proxy response handler to return without terminating the request,
+      break;
-    // so that it can be placed back in the queue.
+    case "requests":
-    reenqueueRequest(req);
+    case "tokens":
-    throw new RetryableError("Rate-limited request re-enqueued.");
+      keyPool.markRateLimited(req.key!);
-  } else {
+      if (errorPayload.error?.message?.match(/on requests per day/)) {
-    // OpenAI probably overloaded
+        // This key has a very low rate limit, so we can't re-enqueue it.
-    errorPayload.proxy_note = `This is likely a temporary error with OpenAI. Try again in a few seconds.`;
+        errorPayload.proxy_note = `Assigned key has reached its per-day request limit for this model. Try another model.`;
+        break;
+      }
+
+      // Per-minute request or token rate limit is exceeded, which we can retry
+      await reenqueueRequest(req);
+      throw new RetryableError("Rate-limited request re-enqueued.");
+    // WIP/nonfunctional
+    // case "tokens_usage_based":
+    //   // Weird new rate limit type that seems limited to preview models.
+    //   // Distinct from `tokens` type. Can be per-minute or per-day.
+    //
+    //   // I've seen reports of this error for 500k tokens/day and 10k tokens/min.
+    //   // 10k tokens per minute is problematic, because this is much less than
+    //   // GPT4-Turbo's max context size for a single prompt and is effectively a
+    //   // cap on the max context size for just that key+model, which the app is
+    //   // not able to deal with.
+    //
+    //   // Similarly if there is a 500k tokens per day limit and 450k tokens have
+    //   // been used today, the max context for that key becomes 50k tokens until
+    //   // the next day and becomes progressively smaller as more tokens are used.
+    //
+    //   // To work around these keys we will first retry the request a few times.
+    //   // After that we will reject the request, and if it's a per-day limit we
+    //   // will also disable the key.
+    //
+    //   // "Rate limit reached for gpt-4-1106-preview in organization org-xxxxxxxxxxxxxxxxxxx on tokens_usage_based per day: Limit 500000, Used 460000, Requested 50000"
+    //   // "Rate limit reached for gpt-4-1106-preview in organization org-xxxxxxxxxxxxxxxxxxx on tokens_usage_based per min: Limit 10000, Requested 40000"
+    //
+    //   const regex =
+    //     /Rate limit reached for .+ in organization .+ on \w+ per (day|min): Limit (\d+)(?:, Used (\d+))?, Requested (\d+)/;
+    //   const [, period, limit, used, requested] =
+    //     errorPayload.error?.message?.match(regex) || [];
+    //
+    //   req.log.warn(
+    //     { key: req.key?.hash, period, limit, used, requested },
+    //     "Received `tokens_usage_based` rate limit error from OpenAI."
+    //   );
+    //
+    //   if (!period || !limit || !requested) {
+    //     errorPayload.proxy_note = `Unrecognized rate limit error from OpenAI. (${errorPayload.error?.message})`;
+    //     break;
+    //   }
+    //
+    //   if (req.retryCount < 2) {
+    //     await reenqueueRequest(req);
+    //     throw new RetryableError("Rate-limited request re-enqueued.");
+    //   }
+    //
+    //   if (period === "min") {
+    //     errorPayload.proxy_note = `Assigned key can't be used for prompts longer than ${limit} tokens, and no other keys are available right now. Reduce the length of your prompt or try again in a few minutes.`;
+    //   } else {
+    //     errorPayload.proxy_note = `Assigned key  has reached its per-day request limit for this model. Try another model.`;
+    //   }
+    //
+    //   keyPool.markRateLimited(req.key!);
+    //   break;
+    default:
+      errorPayload.proxy_note = `This is likely a temporary error with OpenAI. Try again in a few seconds.`;
+      break;
   }
   return errorPayload;
 }
 
+async function handleAzureRateLimitError(
+  req: Request,
+  errorPayload: ProxiedErrorPayload
+) {
+  const code = errorPayload.error?.code;
+  switch (code) {
+    case "429":
+      keyPool.markRateLimited(req.key!);
+      await reenqueueRequest(req);
+      throw new RetryableError("Rate-limited request re-enqueued.");
+    default:
+      errorPayload.proxy_note = `Unrecognized rate limit error from Azure (${code}). Please report this.`;
+      break;
+  }
+}
+
+//{"error":{"code":429,"message":"Resource has been exhausted (e.g. check quota).","status":"RESOURCE_EXHAUSTED"}
+async function handleGoogleAIRateLimitError(
+  req: Request,
+  errorPayload: ProxiedErrorPayload
+) {
+  const status = errorPayload.error?.status;
+  switch (status) {
+    case "RESOURCE_EXHAUSTED":
+      keyPool.markRateLimited(req.key!);
+      await reenqueueRequest(req);
+      throw new RetryableError("Rate-limited request re-enqueued.");
+    default:
+      errorPayload.proxy_note = `Unrecognized rate limit error from Google AI (${status}). Please report this.`;
+      break;
+  }
+}
+
 const incrementUsage: ProxyResHandlerWithBody = async (_proxyRes, req) => {
-  if (isCompletionRequest(req)) {
+  if (isTextGenerationRequest(req) || isImageGenerationRequest(req)) {
     const model = req.body.model;
     const tokensUsed = req.promptTokens! + req.outputTokens!;
+    req.log.debug(
+      {
+        model,
+        tokensUsed,
+        promptTokens: req.promptTokens,
+        outputTokens: req.outputTokens,
+      },
+      `Incrementing usage for model`
+    );
     keyPool.incrementUsage(req.key!, model, tokensUsed);
     if (req.user) {
       incrementPromptCount(req.user.token);
-      incrementTokenCount(req.user.token, model, tokensUsed);
+      incrementTokenCount(req.user.token, model, req.outboundApi, tokensUsed);
     }
   }
 };
@@ -450,30 +649,33 @@ const countResponseTokens: ProxyResHandlerWithBody = async (
   _res,
   body
 ) => {
+  if (req.outboundApi === "openai-image") {
+    req.outputTokens = req.promptTokens;
+    req.promptTokens = 0;
+    return;
+  }
+
   // This function is prone to breaking if the upstream API makes even minor
   // changes to the response format, especially for SSE responses. If you're
   // seeing errors in this function, check the reassembled response body from
   // handleStreamedResponse to see if the upstream API has changed.
   try {
-    if (typeof body !== "object") {
+    assertJsonResponse(body);
-      throw new Error("Expected body to be an object");
-    }
-
     const service = req.outboundApi;
-    const { completion } = getCompletionForService({ req, service, body });
+    const completion = getCompletionFromBody(req, body);
     const tokens = await countTokens({ req, completion, service });
 
     req.log.debug(
       { service, tokens, prevOutputTokens: req.outputTokens },
       `Counted tokens for completion`
     );
-    if (req.debug) {
+    if (req.tokenizerInfo) {
-      req.debug.completion_tokens = tokens;
+      req.tokenizerInfo.completion_tokens = tokens;
     }
 
     req.outputTokens = tokens.token_count;
   } catch (error) {
-    req.log.error(
+    req.log.warn(
       error,
       "Error while counting completion tokens; assuming `max_output_tokens`"
     );
@@ -505,3 +707,46 @@ const copyHttpHeaders: ProxyResHandlerWithBody = async (
     res.setHeader(key, proxyRes.headers[key] as string);
   });
 };
+
+/**
+ * Injects metadata into the response, such as the tokenizer used, logging
+ * status, upstream API endpoint used, and whether the input prompt was modified
+ * or transformed.
+ * Only used for non-streaming requests.
+ */
+const addProxyInfo: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  res,
+  body
+) => {
+  const { service, inboundApi, outboundApi, tokenizerInfo } = req;
+  const native = inboundApi === outboundApi;
+  const info: any = {
+    logged: config.promptLogging,
+    tokens: tokenizerInfo,
+    service,
+    in_api: inboundApi,
+    out_api: outboundApi,
+    prompt_transformed: !native,
+  };
+
+  if (req.query?.debug?.length) {
+    info.final_request_body = req.signedRequest?.body || req.body;
+  }
+
+  if (typeof body === "object") {
+    body.proxy = info;
+  }
+};
+
+function getAwsErrorType(header: string | string[] | undefined) {
+  const val = String(header).match(/^(\w+):?/)?.[1];
+  return val || String(header);
+}
+
+function assertJsonResponse(body: any): asserts body is Record<string, any> {
+  if (typeof body !== "object") {
+    throw new Error("Expected response to be an object");
+  }
+}

src/proxy/middleware/response/log-prompt.ts

@@ -1,9 +1,21 @@
 import { Request } from "express";
 import { config } from "../../../config";
 import { logQueue } from "../../../shared/prompt-logging";
-import { getCompletionForService, isCompletionRequest } from "../common";
+import {
+  getCompletionFromBody,
+  getModelFromBody,
+  isImageGenerationRequest,
+  isTextGenerationRequest,
+} from "../common";
 import { ProxyResHandlerWithBody } from ".";
 import { assertNever } from "../../../shared/utils";
+import {
+  AnthropicChatMessage,
+  flattenAnthropicMessages,
+  MistralAIChatMessage,
+  OpenAIChatMessage,
+} from "../../../shared/api-support";
+import { APIFormat } from "../../../shared/key-management";
 
 /** If prompt logging is enabled, enqueues the prompt for logging. */
 export const logPrompt: ProxyResHandlerWithBody = async (
@@ -19,52 +31,99 @@ export const logPrompt: ProxyResHandlerWithBody = async (
     throw new Error("Expected body to be an object");
   }
 
-  if (!isCompletionRequest(req)) {
+  const loggable =
-    return;
+    isTextGenerationRequest(req) || isImageGenerationRequest(req);
-  }
+  if (!loggable) return;
 
-  const promptPayload = getPromptForRequest(req);
+  const promptPayload = getPromptForRequest(req, responseBody);
-  const promptFlattened = flattenMessages(promptPayload);
+  const promptFlattened = flattenMessages(promptPayload, req.outboundApi);
-  const response = getCompletionForService({
+  const response = getCompletionFromBody(req, responseBody);
-    service: req.outboundApi,
+  const model = getModelFromBody(req, responseBody);
-    body: responseBody,
-  });
 
   logQueue.enqueue({
     endpoint: req.inboundApi,
     promptRaw: JSON.stringify(promptPayload),
     promptFlattened,
-    model: response.model, // may differ from the requested model
+    model,
-    response: response.completion,
+    response,
   });
 };
 
-type OaiMessage = {
+type OaiImageResult = {
-  role: "user" | "assistant" | "system";
+  prompt: string;
-  content: string;
+  size: string;
+  style: string;
+  quality: string;
+  revisedPrompt?: string;
 };
 
-const getPromptForRequest = (req: Request): string | OaiMessage[] => {
+const getPromptForRequest = (
+  req: Request,
+  responseBody: Record<string, any>
+):
+  | string
+  | OpenAIChatMessage[]
+  | AnthropicChatMessage[]
+  | MistralAIChatMessage[]
+  | OaiImageResult => {
   // Since the prompt logger only runs after the request has been proxied, we
   // can assume the body has already been transformed to the target API's
   // format.
   switch (req.outboundApi) {
     case "openai":
+    case "mistral-ai":
+    case "anthropic-chat":
       return req.body.messages;
     case "openai-text":
       return req.body.prompt;
-    case "anthropic":
+    case "openai-image":
+      return {
+        prompt: req.body.prompt,
+        size: req.body.size,
+        style: req.body.style,
+        quality: req.body.quality,
+        revisedPrompt: responseBody.data[0].revised_prompt,
+      };
+    case "anthropic-text":
       return req.body.prompt;
-    case "google-palm":
+    case "google-ai":
       return req.body.prompt.text;
     default:
       assertNever(req.outboundApi);
   }
 };
 
-const flattenMessages = (messages: string | OaiMessage[]): string => {
+const flattenMessages = (
-  if (typeof messages === "string") {
+  val:
-    return messages.trim();
+    | string
+    | OaiImageResult
+    | OpenAIChatMessage[]
+    | AnthropicChatMessage[]
+    | MistralAIChatMessage[],
+  format: APIFormat
+): string => {
+  if (typeof val === "string") {
+    return val.trim();
   }
-  return messages.map((m) => `${m.role}: ${m.content}`).join("\n");
+  if (format === "anthropic-chat") {
+    return flattenAnthropicMessages(val as AnthropicChatMessage[]);
+  }
+  if (Array.isArray(val)) {
+    return val
+      .map(({ content, role }) => {
+        const text = Array.isArray(content)
+          ? content
+              .map((c) => {
+                if ("text" in c) return c.text;
+                if ("image_url" in c) return "(( Attached Image ))";
+                if ("source" in c) return "(( Attached Image ))";
+                return "(( Unsupported Content ))";
+              })
+              .join("\n")
+          : content;
+        return `${role}: ${text}`;
+      })
+      .join("\n");
+  }
+  return val.prompt.trim();
 };

src/proxy/middleware/response/save-image.ts

@@ -0,0 +1,33 @@
+import { ProxyResHandlerWithBody } from "./index";
+import {
+  mirrorGeneratedImage,
+  OpenAIImageGenerationResult,
+} from "../../../shared/file-storage/mirror-generated-image";
+
+export const saveImage: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  _res,
+  body
+) => {
+  if (req.outboundApi !== "openai-image") {
+    return;
+  }
+
+  if (typeof body !== "object") {
+    throw new Error("Expected body to be an object");
+  }
+
+  if (body.data) {
+    const prompt = body.data[0].revised_prompt ?? req.body.prompt;
+    const res = await mirrorGeneratedImage(
+      req,
+      prompt,
+      body as OpenAIImageGenerationResult
+    );
+    req.log.info(
+      { urls: res.data.map((item) => item.url) },
+      "Saved generated image to user_content"
+    );
+  }
+};

src/proxy/middleware/response/streaming/aggregators/anthropic-chat.ts

@@ -0,0 +1,49 @@
+import { OpenAIChatCompletionStreamEvent } from "../index";
+
+export type AnthropicChatCompletionResponse = {
+  id: string;
+  type: "message";
+  role: "assistant";
+  content: { type: "text"; text: string }[];
+  model: string;
+  stop_reason: string | null;
+  stop_sequence: string | null;
+  usage: { input_tokens: number; output_tokens: number };
+};
+
+/**
+ * Given a list of OpenAI chat completion events, compiles them into a single
+ * finalized Anthropic chat completion response so that non-streaming middleware
+ * can operate on it as if it were a blocking response.
+ */
+export function mergeEventsForAnthropicChat(
+  events: OpenAIChatCompletionStreamEvent[]
+): AnthropicChatCompletionResponse {
+  let merged: AnthropicChatCompletionResponse = {
+    id: "",
+    type: "message",
+    role: "assistant",
+    content: [],
+    model: "",
+    stop_reason: null,
+    stop_sequence: null,
+    usage: { input_tokens: 0, output_tokens: 0 },
+  };
+  merged = events.reduce((acc, event, i) => {
+    // The first event will only contain role assignment and response metadata
+    if (i === 0) {
+      acc.id = event.id;
+      acc.model = event.model;
+      acc.content = [{ type: "text", text: "" }];
+      return acc;
+    }
+
+    acc.stop_reason = event.choices[0].finish_reason ?? "";
+    if (event.choices[0].delta.content) {
+      acc.content[0].text += event.choices[0].delta.content;
+    }
+
+    return acc;
+  }, merged);
+  return merged;
+}

src/proxy/middleware/response/streaming/aggregators/anthropic-text.ts

@@ -0,0 +1,48 @@
+import { OpenAIChatCompletionStreamEvent } from "../index";
+
+export type AnthropicTextCompletionResponse = {
+  completion: string;
+  stop_reason: string;
+  truncated: boolean;
+  stop: any;
+  model: string;
+  log_id: string;
+  exception: null;
+};
+
+/**
+ * Given a list of OpenAI chat completion events, compiles them into a single
+ * finalized Anthropic completion response so that non-streaming middleware
+ * can operate on it as if it were a blocking response.
+ */
+export function mergeEventsForAnthropicText(
+  events: OpenAIChatCompletionStreamEvent[]
+): AnthropicTextCompletionResponse {
+  let merged: AnthropicTextCompletionResponse = {
+    log_id: "",
+    exception: null,
+    model: "",
+    completion: "",
+    stop_reason: "",
+    truncated: false,
+    stop: null,
+  };
+  merged = events.reduce((acc, event, i) => {
+    // The first event will only contain role assignment and response metadata
+    if (i === 0) {
+      acc.log_id = event.id;
+      acc.model = event.model;
+      acc.completion = "";
+      acc.stop_reason = "";
+      return acc;
+    }
+
+    acc.stop_reason = event.choices[0].finish_reason ?? "";
+    if (event.choices[0].delta.content) {
+      acc.completion += event.choices[0].delta.content;
+    }
+
+    return acc;
+  }, merged);
+  return merged;
+}

src/proxy/middleware/response/streaming/aggregators/openai-chat.ts

@@ -0,0 +1,58 @@
+import { OpenAIChatCompletionStreamEvent } from "../index";
+
+export type OpenAiChatCompletionResponse = {
+  id: string;
+  object: string;
+  created: number;
+  model: string;
+  choices: {
+    message: { role: string; content: string };
+    finish_reason: string | null;
+    index: number;
+  }[];
+};
+
+/**
+ * Given a list of OpenAI chat completion events, compiles them into a single
+ * finalized OpenAI chat completion response so that non-streaming middleware
+ * can operate on it as if it were a blocking response.
+ */
+export function mergeEventsForOpenAIChat(
+  events: OpenAIChatCompletionStreamEvent[]
+): OpenAiChatCompletionResponse {
+  let merged: OpenAiChatCompletionResponse = {
+    id: "",
+    object: "",
+    created: 0,
+    model: "",
+    choices: [],
+  };
+  merged = events.reduce((acc, event, i) => {
+    // The first event will only contain role assignment and response metadata
+    if (i === 0) {
+      acc.id = event.id;
+      acc.object = event.object;
+      acc.created = event.created;
+      acc.model = event.model;
+      acc.choices = [
+        {
+          index: 0,
+          message: {
+            role: event.choices[0].delta.role ?? "assistant",
+            content: "",
+          },
+          finish_reason: null,
+        },
+      ];
+      return acc;
+    }
+
+    acc.choices[0].finish_reason = event.choices[0].finish_reason;
+    if (event.choices[0].delta.content) {
+      acc.choices[0].message.content += event.choices[0].delta.content;
+    }
+
+    return acc;
+  }, merged);
+  return merged;
+}

src/proxy/middleware/response/streaming/aggregators/openai-text.ts

@@ -0,0 +1,57 @@
+import { OpenAIChatCompletionStreamEvent } from "../index";
+
+export type OpenAiTextCompletionResponse = {
+  id: string;
+  object: string;
+  created: number;
+  model: string;
+  choices: {
+    text: string;
+    finish_reason: string | null;
+    index: number;
+    logprobs: null;
+  }[];
+};
+
+/**
+ * Given a list of OpenAI chat completion events, compiles them into a single
+ * finalized OpenAI text completion response so that non-streaming middleware
+ * can operate on it as if it were a blocking response.
+ */
+export function mergeEventsForOpenAIText(
+  events: OpenAIChatCompletionStreamEvent[]
+): OpenAiTextCompletionResponse {
+  let merged: OpenAiTextCompletionResponse = {
+    id: "",
+    object: "",
+    created: 0,
+    model: "",
+    choices: [],
+  };
+  merged = events.reduce((acc, event, i) => {
+    // The first event will only contain role assignment and response metadata
+    if (i === 0) {
+      acc.id = event.id;
+      acc.object = event.object;
+      acc.created = event.created;
+      acc.model = event.model;
+      acc.choices = [
+        {
+          text: "",
+          index: 0,
+          finish_reason: null,
+          logprobs: null,
+        },
+      ];
+      return acc;
+    }
+
+    acc.choices[0].finish_reason = event.choices[0].finish_reason;
+    if (event.choices[0].delta.content) {
+      acc.choices[0].text += event.choices[0].delta.content;
+    }
+
+    return acc;
+  }, merged);
+  return merged;
+}

src/proxy/middleware/response/streaming/aws-event-stream-decoder.ts

@@ -0,0 +1,93 @@
+import pino from "pino";
+import { Duplex, Readable } from "stream";
+import { EventStreamMarshaller } from "@smithy/eventstream-serde-node";
+import { fromUtf8, toUtf8 } from "@smithy/util-utf8";
+import { Message } from "@smithy/eventstream-codec";
+
+/**
+ * Decodes a Readable stream, such as a proxied HTTP response, into a stream of
+ * Message objects using the AWS SDK's EventStreamMarshaller. Error events in
+ * the amazon eventstream protocol are decoded as Message objects and will not
+ * emit an error event on the decoder stream.
+ */
+export function getAwsEventStreamDecoder(params: {
+  input: Readable;
+  logger: pino.Logger;
+}): Duplex {
+  const { input, logger } = params;
+  const config = { utf8Encoder: toUtf8, utf8Decoder: fromUtf8 };
+  const eventStream = new EventStreamMarshaller(config).deserialize(
+    input,
+    async (input: Record<string, Message>) => {
+      const eventType = Object.keys(input)[0];
+      let result;
+      if (eventType === "chunk") {
+        result = input[eventType];
+      } else {
+        // AWS unmarshaller treats non-chunk (errors and exceptions) oddly.
+        result = { [eventType]: input[eventType] } as any;
+      }
+      return result;
+    }
+  );
+  return new AWSEventStreamDecoder(eventStream, { logger });
+}
+
+class AWSEventStreamDecoder extends Duplex {
+  private readonly asyncIterable: AsyncIterable<Message>;
+  private iterator: AsyncIterator<Message>;
+  private reading: boolean;
+  private logger: pino.Logger;
+
+  constructor(
+    asyncIterable: AsyncIterable<Message>,
+    options: { logger: pino.Logger }
+  ) {
+    super({ ...options, objectMode: true });
+    this.asyncIterable = asyncIterable;
+    this.iterator = this.asyncIterable[Symbol.asyncIterator]();
+    this.reading = false;
+    this.logger = options.logger.child({ module: "aws-eventstream-decoder" });
+  }
+
+  async _read(_size: number) {
+    if (this.reading) return;
+    this.reading = true;
+
+    try {
+      while (true) {
+        const { value, done } = await this.iterator.next();
+        if (done) {
+          this.push(null);
+          break;
+        }
+        if (!this.push(value)) break;
+      }
+    } catch (err) {
+      // AWS SDK's EventStreamMarshaller emits errors in the stream itself as
+      // whatever our deserializer returns, which will not be Error objects
+      // because we want to pass the Message to the next stream for processing.
+      // Any actual Error thrown here is some failure during deserialization.
+      const isAwsError = !(err instanceof Error);
+
+      if (isAwsError) {
+        this.logger.warn({ err: err.headers }, "Received AWS error event");
+        this.push(err);
+        this.push(null);
+      } else {
+        this.logger.error(err, "Error during AWS stream deserialization");
+        this.destroy(err);
+      }
+    } finally {
+      this.reading = false;
+    }
+  }
+
+  _write(_chunk: any, _encoding: string, callback: () => void) {
+    callback();
+  }
+
+  _final(callback: () => void) {
+    callback();
+  }
+}

src/proxy/middleware/response/streaming/event-aggregator.ts

@@ -0,0 +1,76 @@
+import { APIFormat } from "../../../../shared/key-management";
+import { assertNever } from "../../../../shared/utils";
+import {
+  anthropicV2ToOpenAI,
+  mergeEventsForAnthropicChat,
+  mergeEventsForAnthropicText,
+  mergeEventsForOpenAIChat,
+  mergeEventsForOpenAIText,
+  AnthropicV2StreamEvent,
+  OpenAIChatCompletionStreamEvent,
+} from "./index";
+
+/**
+ * Collects SSE events containing incremental chat completion responses and
+ * compiles them into a single finalized response for downstream middleware.
+ */
+export class EventAggregator {
+  private readonly format: APIFormat;
+  private readonly events: OpenAIChatCompletionStreamEvent[];
+
+  constructor({ format }: { format: APIFormat }) {
+    this.events = [];
+    this.format = format;
+  }
+
+  addEvent(event: OpenAIChatCompletionStreamEvent | AnthropicV2StreamEvent) {
+    if (eventIsOpenAIEvent(event)) {
+      this.events.push(event);
+    } else {
+      // horrible special case. previously all transformers' target format was
+      // openai, so the event aggregator could conveniently assume all incoming
+      // events were in openai format.
+      // now we have added anthropic-chat-to-text, so aggregator needs to know
+      // how to collapse events from two formats.
+      // because that is annoying, we will simply transform anthropic events to
+      // openai (even if the client didn't ask for openai) so we don't have to
+      // write aggregation logic for anthropic chat (which is also a troublesome
+      // stateful format).
+      const openAIEvent = anthropicV2ToOpenAI({
+        data: `event: completion\ndata: ${JSON.stringify(event)}\n\n`,
+        lastPosition: -1,
+        index: 0,
+        fallbackId: event.log_id || "event-aggregator-fallback",
+        fallbackModel: event.model || "claude-3-fallback",
+      });
+      if (openAIEvent.event) {
+        this.events.push(openAIEvent.event);
+      }
+    }
+  }
+
+  getFinalResponse() {
+    switch (this.format) {
+      case "openai":
+      case "google-ai":
+      case "mistral-ai":
+        return mergeEventsForOpenAIChat(this.events);
+      case "openai-text":
+        return mergeEventsForOpenAIText(this.events);
+      case "anthropic-text":
+        return mergeEventsForAnthropicText(this.events);
+      case "anthropic-chat":
+        return mergeEventsForAnthropicChat(this.events);
+      case "openai-image":
+        throw new Error(`SSE aggregation not supported for ${this.format}`);
+      default:
+        assertNever(this.format);
+    }
+  }
+}
+
+function eventIsOpenAIEvent(
+  event: any
+): event is OpenAIChatCompletionStreamEvent {
+  return event?.object === "chat.completion.chunk";
+}

src/proxy/middleware/response/streaming/index.ts

@@ -0,0 +1,48 @@
+export type SSEResponseTransformArgs<S = Record<string, any>> = {
+  data: string;
+  lastPosition: number;
+  index: number;
+  fallbackId: string;
+  fallbackModel: string;
+  state?: S;
+};
+
+export type AnthropicV2StreamEvent = {
+  log_id?: string;
+  model?: string;
+  completion: string;
+  stop_reason: string | null;
+};
+
+export type OpenAIChatCompletionStreamEvent = {
+  id: string;
+  object: "chat.completion.chunk";
+  created: number;
+  model: string;
+  choices: {
+    index: number;
+    delta: { role?: string; content?: string };
+    finish_reason: string | null;
+  }[];
+};
+
+export type StreamingCompletionTransformer<
+  T = OpenAIChatCompletionStreamEvent,
+  S = any,
+> = (params: SSEResponseTransformArgs<S>) => {
+  position: number;
+  event?: T;
+  state?: S;
+};
+
+export { openAITextToOpenAIChat } from "./transformers/openai-text-to-openai";
+export { anthropicV1ToOpenAI } from "./transformers/anthropic-v1-to-openai";
+export { anthropicV2ToOpenAI } from "./transformers/anthropic-v2-to-openai";
+export { anthropicChatToAnthropicV2 } from "./transformers/anthropic-chat-to-anthropic-v2";
+export { anthropicChatToOpenAI } from "./transformers/anthropic-chat-to-openai";
+export { googleAIToOpenAI } from "./transformers/google-ai-to-openai";
+export { passthroughToOpenAI } from "./transformers/passthrough-to-openai";
+export { mergeEventsForOpenAIChat } from "./aggregators/openai-chat";
+export { mergeEventsForOpenAIText } from "./aggregators/openai-text";
+export { mergeEventsForAnthropicText } from "./aggregators/anthropic-text";
+export { mergeEventsForAnthropicChat } from "./aggregators/anthropic-chat";

src/proxy/middleware/response/streaming/parse-sse.ts

@@ -0,0 +1,29 @@
+export type ServerSentEvent = { id?: string; type?: string; data: string };
+
+/** Given a string of SSE data, parse it into a `ServerSentEvent` object. */
+export function parseEvent(event: string) {
+  const buffer: ServerSentEvent = { data: "" };
+  return event.split(/\r?\n/).reduce(parseLine, buffer);
+}
+
+function parseLine(event: ServerSentEvent, line: string) {
+  const separator = line.indexOf(":");
+  const field = separator === -1 ? line : line.slice(0, separator);
+  const value = separator === -1 ? "" : line.slice(separator + 1);
+
+  switch (field) {
+    case "id":
+      event.id = value.trim();
+      break;
+    case "event":
+      event.type = value.trim();
+      break;
+    case "data":
+      event.data += value.trimStart();
+      break;
+    default:
+      break;
+  }
+
+  return event;
+}

src/proxy/middleware/response/streaming/sse-message-transformer.ts

@@ -0,0 +1,170 @@
+import { Transform, TransformOptions } from "stream";
+import { logger } from "../../../../logger";
+import { APIFormat } from "../../../../shared/key-management";
+import { assertNever } from "../../../../shared/utils";
+import {
+  anthropicChatToOpenAI,
+  anthropicChatToAnthropicV2,
+  anthropicV1ToOpenAI,
+  AnthropicV2StreamEvent,
+  anthropicV2ToOpenAI,
+  googleAIToOpenAI,
+  OpenAIChatCompletionStreamEvent,
+  openAITextToOpenAIChat,
+  passthroughToOpenAI,
+  StreamingCompletionTransformer,
+} from "./index";
+
+type SSEMessageTransformerOptions = TransformOptions & {
+  requestedModel: string;
+  requestId: string;
+  inputFormat: APIFormat;
+  inputApiVersion?: string;
+  outputFormat?: APIFormat;
+  logger: typeof logger;
+};
+
+/**
+ * Transforms SSE messages from one API format to OpenAI chat.completion.chunks.
+ * Emits the original string SSE message as an "originalMessage" event.
+ */
+export class SSEMessageTransformer extends Transform {
+  private lastPosition: number;
+  private transformState: any;
+  private msgCount: number;
+  private readonly inputFormat: APIFormat;
+  private readonly transformFn: StreamingCompletionTransformer<
+    // TODO: Refactor transformers to not assume only OpenAI events as output
+    OpenAIChatCompletionStreamEvent | AnthropicV2StreamEvent
+  >;
+  private readonly log;
+  private readonly fallbackId: string;
+  private readonly fallbackModel: string;
+
+  constructor(options: SSEMessageTransformerOptions) {
+    super({ ...options, readableObjectMode: true });
+    this.log = options.logger?.child({ module: "sse-transformer" });
+    this.lastPosition = 0;
+    this.msgCount = 0;
+    this.transformFn = getTransformer(
+      options.inputFormat,
+      options.inputApiVersion,
+      options.outputFormat
+    );
+    this.inputFormat = options.inputFormat;
+    this.fallbackId = options.requestId;
+    this.fallbackModel = options.requestedModel;
+    this.log.debug(
+      {
+        fn: this.transformFn.name,
+        format: options.inputFormat,
+        version: options.inputApiVersion,
+      },
+      "Selected SSE transformer"
+    );
+  }
+
+  _transform(chunk: Buffer, _encoding: BufferEncoding, callback: Function) {
+    try {
+      const originalMessage = chunk.toString();
+      const {
+        event: transformedMessage,
+        position: newPosition,
+        state,
+      } = this.transformFn({
+        data: originalMessage,
+        lastPosition: this.lastPosition,
+        index: this.msgCount++,
+        fallbackId: this.fallbackId,
+        fallbackModel: this.fallbackModel,
+        state: this.transformState,
+      });
+      this.lastPosition = newPosition;
+      this.transformState = state;
+
+      // Special case for Azure OpenAI, which is 99% the same as OpenAI but
+      // sometimes emits an extra event at the beginning of the stream with the
+      // content moderation system's response to the prompt. A lot of frontends
+      // don't expect this and neither does our event aggregator so we drop it.
+      if (this.inputFormat === "openai" && this.msgCount <= 1) {
+        if (originalMessage.includes("prompt_filter_results")) {
+          this.log.debug("Dropping Azure OpenAI content moderation SSE event");
+          return callback();
+        }
+      }
+
+      this.emit("originalMessage", originalMessage);
+
+      // Some events may not be transformed, e.g. ping events
+      if (!transformedMessage) return callback();
+
+      if (this.msgCount === 1 && eventIsOpenAIEvent(transformedMessage)) {
+        // TODO: does this need to be skipped for passthroughToOpenAI?
+        this.push(createInitialMessage(transformedMessage));
+      }
+      this.push(transformedMessage);
+      callback();
+    } catch (err) {
+      err.lastEvent = chunk?.toString();
+      this.log.error(err, "Error transforming SSE message");
+      callback(err);
+    }
+  }
+}
+
+function eventIsOpenAIEvent(
+  event: any
+): event is OpenAIChatCompletionStreamEvent {
+  return event?.object === "chat.completion.chunk";
+}
+
+function getTransformer(
+  responseApi: APIFormat,
+  version?: string,
+  // There's only one case where we're not transforming back to OpenAI, which is
+  // Anthropic Chat response -> Anthropic Text request. This parameter is only
+  // used for that case.
+  requestApi: APIFormat = "openai"
+): StreamingCompletionTransformer<
+  OpenAIChatCompletionStreamEvent | AnthropicV2StreamEvent
+> {
+  switch (responseApi) {
+    case "openai":
+    case "mistral-ai":
+      return passthroughToOpenAI;
+    case "openai-text":
+      return openAITextToOpenAIChat;
+    case "anthropic-text":
+      return version === "2023-01-01"
+        ? anthropicV1ToOpenAI
+        : anthropicV2ToOpenAI;
+    case "anthropic-chat":
+      return requestApi === "anthropic-text"
+        ? anthropicChatToAnthropicV2
+        : anthropicChatToOpenAI;
+    case "google-ai":
+      return googleAIToOpenAI;
+    case "openai-image":
+      throw new Error(`SSE transformation not supported for ${responseApi}`);
+    default:
+      assertNever(responseApi);
+  }
+}
+
+/**
+ * OpenAI streaming chat completions start with an event that contains only the
+ * metadata and role (always 'assistant') for the response.  To simulate this
+ * for APIs where the first event contains actual content, we create a fake
+ * initial event with no content but correct metadata.
+ */
+function createInitialMessage(
+  event: OpenAIChatCompletionStreamEvent
+): OpenAIChatCompletionStreamEvent {
+  return {
+    ...event,
+    choices: event.choices.map((choice) => ({
+      ...choice,
+      delta: { role: "assistant", content: "" },
+    })),
+  };
+}

src/proxy/middleware/response/streaming/sse-stream-adapter.ts

@@ -0,0 +1,174 @@
+import pino from "pino";
+import { Transform, TransformOptions } from "stream";
+import { Message } from "@smithy/eventstream-codec";
+import { APIFormat } from "../../../../shared/key-management";
+import { RetryableError } from "../index";
+import { buildSpoofedSSE } from "../error-generator";
+import { BadRequestError } from "../../../../shared/errors";
+
+type SSEStreamAdapterOptions = TransformOptions & {
+  contentType?: string;
+  api: APIFormat;
+  logger: pino.Logger;
+};
+
+/**
+ * Receives a stream of events in a variety of formats and transforms them into
+ * Server-Sent Events.
+ *
+ * This is an object-mode stream, so it expects to receive objects and will emit
+ * strings.
+ */
+export class SSEStreamAdapter extends Transform {
+  private readonly isAwsStream;
+  private readonly isGoogleStream;
+  private api: APIFormat;
+  private partialMessage = "";
+  private textDecoder = new TextDecoder("utf8");
+  private log: pino.Logger;
+
+  constructor(options: SSEStreamAdapterOptions) {
+    super({ ...options, objectMode: true });
+    this.isAwsStream =
+      options?.contentType === "application/vnd.amazon.eventstream";
+    this.isGoogleStream = options?.api === "google-ai";
+    this.api = options.api;
+    this.log = options.logger.child({ module: "sse-stream-adapter" });
+  }
+
+  protected processAwsMessage(message: Message): string | null {
+    // Per amazon, headers and body are always present. headers is an object,
+    // body is a Uint8Array, potentially zero-length.
+    const { headers, body } = message;
+    const eventType = headers[":event-type"]?.value;
+    const messageType = headers[":message-type"]?.value;
+    const contentType = headers[":content-type"]?.value;
+    const exceptionType = headers[":exception-type"]?.value;
+    const errorCode = headers[":error-code"]?.value;
+    const bodyStr = this.textDecoder.decode(body);
+
+    switch (messageType) {
+      case "event":
+        if (contentType === "application/json" && eventType === "chunk") {
+          const { bytes } = JSON.parse(bodyStr);
+          const event = Buffer.from(bytes, "base64").toString("utf8");
+          const eventObj = JSON.parse(event);
+
+          if ("completion" in eventObj) {
+            return ["event: completion", `data: ${event}`].join(`\n`);
+          } else {
+            return [`event: ${eventObj.type}`, `data: ${event}`].join(`\n`);
+          }
+        }
+      // noinspection FallThroughInSwitchStatementJS -- non-JSON data is unexpected
+      case "exception":
+      case "error":
+        const type = String(
+          exceptionType || errorCode || "UnknownError"
+        ).toLowerCase();
+        switch (type) {
+          case "throttlingexception":
+            this.log.warn(
+              "AWS request throttled after streaming has already started; retrying"
+            );
+            throw new RetryableError("AWS request throttled mid-stream");
+          case "validationexception":
+            try {
+              const { message } = JSON.parse(bodyStr);
+              this.log.error({ message }, "Received AWS validation error");
+              this.emit(
+                "error",
+                new BadRequestError(`AWS validation error: ${message}`)
+              );
+              return null;
+            } catch (error) {
+              this.log.error(
+                { body: bodyStr, error },
+                "Could not parse AWS validation error"
+              );
+            }
+          // noinspection FallThroughInSwitchStatementJS -- who knows what this is
+          default:
+            let text;
+            try {
+              text = JSON.parse(bodyStr).message;
+            } catch (error) {
+              text = bodyStr;
+            }
+            const error: any = new Error(
+              `Got mysterious error chunk: [${type}] ${text}`
+            );
+            error.lastEvent = text;
+            this.emit("error", error);
+            return null;
+        }
+      default:
+        // Amazon says this can't ever happen...
+        this.log.error({ message }, "Received very bad AWS stream event");
+        return null;
+    }
+  }
+
+  /** Processes an incoming array element from the Google AI JSON stream. */
+  protected processGoogleObject(data: any): string | null {
+    // Sometimes data has fields key and value, sometimes it's just the
+    // candidates array.
+    const candidates = data.value?.candidates ?? data.candidates ?? [{}];
+    try {
+      const hasParts = candidates[0].content?.parts?.length > 0;
+      if (hasParts) {
+        return `data: ${JSON.stringify(data)}`;
+      } else {
+        this.log.error({ event: data }, "Received bad Google AI event");
+        return `data: ${buildSpoofedSSE({
+          format: "google-ai",
+          title: "Proxy stream error",
+          message:
+            "The proxy received malformed or unexpected data from Google AI while streaming.",
+          obj: data,
+          reqId: "proxy-sse-adapter-message",
+          model: "",
+        })}`;
+      }
+    } catch (error) {
+      error.lastEvent = data;
+      this.emit("error", error);
+    }
+    return null;
+  }
+
+  _transform(data: any, _enc: string, callback: (err?: Error | null) => void) {
+    try {
+      if (this.isAwsStream) {
+        // `data` is a Message object
+        const message = this.processAwsMessage(data);
+        if (message) this.push(message + "\n\n");
+      } else if (this.isGoogleStream) {
+        // `data` is an element from the Google AI JSON stream
+        const message = this.processGoogleObject(data);
+        if (message) this.push(message + "\n\n");
+      } else {
+        // `data` is a string, but possibly only a partial message
+        const fullMessages = (this.partialMessage + data).split(
+          /\r\r|\n\n|\r\n\r\n/
+        );
+        this.partialMessage = fullMessages.pop() || "";
+
+        for (const message of fullMessages) {
+          // Mixing line endings will break some clients and our request queue
+          // will have already sent \n for heartbeats, so we need to normalize
+          // to \n.
+          this.push(message.replace(/\r\n?/g, "\n") + "\n\n");
+        }
+      }
+      callback();
+    } catch (error) {
+      error.lastEvent = data?.toString() ?? "[SSEStreamAdapter] no data";
+      callback(error);
+    }
+  }
+
+  _flush(callback: (err?: Error | null) => void) {
+    callback();
+  }
+}

src/proxy/middleware/response/streaming/transformers/anthropic-chat-to-anthropic-v2.ts

@@ -0,0 +1,129 @@
+import {
+  AnthropicV2StreamEvent,
+  StreamingCompletionTransformer,
+} from "../index";
+import { parseEvent, ServerSentEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "anthropic-chat-to-anthropic-v2",
+});
+
+export type AnthropicChatEventType =
+  | "message_start"
+  | "content_block_start"
+  | "content_block_delta"
+  | "content_block_stop"
+  | "message_delta"
+  | "message_stop";
+
+type AnthropicChatStartEvent = {
+  type: "message_start";
+  message: {
+    id: string;
+    type: "message";
+    role: "assistant";
+    content: [];
+    model: string;
+    stop_reason: null;
+    stop_sequence: null;
+    usage: { input_tokens: number; output_tokens: number };
+  };
+};
+
+type AnthropicChatContentBlockStartEvent = {
+  type: "content_block_start";
+  index: number;
+  content_block: { type: "text"; text: string };
+};
+
+export type AnthropicChatContentBlockDeltaEvent = {
+  type: "content_block_delta";
+  index: number;
+  delta: { type: "text_delta"; text: string };
+};
+
+type AnthropicChatContentBlockStopEvent = {
+  type: "content_block_stop";
+  index: number;
+};
+
+type AnthropicChatMessageDeltaEvent = {
+  type: "message_delta";
+  delta: {
+    stop_reason: string;
+    stop_sequence: null;
+    usage: { output_tokens: number };
+  };
+};
+
+type AnthropicChatMessageStopEvent = {
+  type: "message_stop";
+};
+
+type AnthropicChatTransformerState = { content: string };
+
+/**
+ * Transforms an incoming Anthropic Chat SSE to an equivalent Anthropic V2
+ * Text SSE.
+ * For now we assume there is only one content block and message delta. In the
+ * future Anthropic may add multi-turn responses or multiple content blocks
+ * (probably for multimodal responses, image generation, etc) but as far as I
+ * can tell this is not yet implemented.
+ */
+export const anthropicChatToAnthropicV2: StreamingCompletionTransformer<
+  AnthropicV2StreamEvent,
+  AnthropicChatTransformerState
+> = (params) => {
+  const { data } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || !rawEvent.type) {
+    return { position: -1 };
+  }
+
+  const deltaEvent = asAnthropicChatDelta(rawEvent);
+  if (!deltaEvent) {
+    return { position: -1 };
+  }
+
+  const newEvent = {
+    log_id: params.fallbackId,
+    model: params.fallbackModel,
+    completion: deltaEvent.delta.text,
+    stop_reason: null,
+  };
+
+  return { position: -1, event: newEvent };
+};
+
+export function asAnthropicChatDelta(
+  event: ServerSentEvent
+): AnthropicChatContentBlockDeltaEvent | null {
+  if (
+    !event.type ||
+    !["content_block_start", "content_block_delta"].includes(event.type)
+  ) {
+    return null;
+  }
+
+  try {
+    const parsed = JSON.parse(event.data);
+    if (parsed.type === "content_block_delta") {
+      return parsed;
+    } else if (parsed.type === "content_block_start") {
+      return {
+        type: "content_block_delta",
+        index: parsed.index,
+        delta: { type: "text_delta", text: parsed.content_block?.text ?? "" },
+      };
+    } else {
+      // noinspection ExceptionCaughtLocallyJS
+      throw new Error("Invalid event type");
+    }
+  } catch (error) {
+    log.warn({ error: error.stack, event }, "Received invalid event");
+  }
+  return null;
+}

src/proxy/middleware/response/streaming/transformers/anthropic-chat-to-openai.ts

@@ -0,0 +1,45 @@
+import { StreamingCompletionTransformer } from "../index";
+import { parseEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+import { asAnthropicChatDelta } from "./anthropic-chat-to-anthropic-v2";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "anthropic-chat-to-openai",
+});
+
+/**
+ * Transforms an incoming Anthropic Chat SSE to an equivalent OpenAI
+ * chat.completion.chunks SSE.
+ */
+export const anthropicChatToOpenAI: StreamingCompletionTransformer = (
+  params
+) => {
+  const { data } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || !rawEvent.type) {
+    return { position: -1 };
+  }
+
+  const deltaEvent = asAnthropicChatDelta(rawEvent);
+  if (!deltaEvent) {
+    return { position: -1 };
+  }
+
+  const newEvent = {
+    id: params.fallbackId,
+    object: "chat.completion.chunk" as const,
+    created: Date.now(),
+    model: params.fallbackModel,
+    choices: [
+      {
+        index: params.index,
+        delta: { content: deltaEvent.delta.text },
+        finish_reason: null,
+      },
+    ],
+  };
+
+  return { position: -1, event: newEvent };
+};

src/proxy/middleware/response/streaming/transformers/anthropic-v1-to-openai.ts

@@ -0,0 +1,67 @@
+import { StreamingCompletionTransformer } from "../index";
+import { parseEvent, ServerSentEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "anthropic-v1-to-openai",
+});
+
+type AnthropicV1StreamEvent = {
+  log_id?: string;
+  model?: string;
+  completion: string;
+  stop_reason: string;
+};
+
+/**
+ * Transforms an incoming Anthropic SSE (2023-01-01 API) to an equivalent
+ * OpenAI chat.completion.chunk SSE.
+ */
+export const anthropicV1ToOpenAI: StreamingCompletionTransformer = (params) => {
+  const { data, lastPosition } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || rawEvent.data === "[DONE]") {
+    return { position: lastPosition };
+  }
+
+  const completionEvent = asCompletion(rawEvent);
+  if (!completionEvent) {
+    return { position: lastPosition };
+  }
+
+  // Anthropic sends the full completion so far with each event whereas OpenAI
+  // only sends the delta. To make the SSE events compatible, we remove
+  // everything before `lastPosition` from the completion.
+  const newEvent = {
+    id: "ant-" + (completionEvent.log_id ?? params.fallbackId),
+    object: "chat.completion.chunk" as const,
+    created: Date.now(),
+    model: completionEvent.model ?? params.fallbackModel,
+    choices: [
+      {
+        index: 0,
+        delta: { content: completionEvent.completion?.slice(lastPosition) },
+        finish_reason: completionEvent.stop_reason,
+      },
+    ],
+  };
+
+  return { position: completionEvent.completion.length, event: newEvent };
+};
+
+function asCompletion(event: ServerSentEvent): AnthropicV1StreamEvent | null {
+  try {
+    const parsed = JSON.parse(event.data);
+    if (parsed.completion !== undefined && parsed.stop_reason !== undefined) {
+      return parsed;
+    } else {
+      // noinspection ExceptionCaughtLocallyJS
+      throw new Error("Missing required fields");
+    }
+  } catch (error) {
+    log.warn({ error: error.stack, event }, "Received invalid event");
+  }
+  return null;
+}

src/proxy/middleware/response/streaming/transformers/anthropic-v2-to-openai.ts

@@ -0,0 +1,62 @@
+import {
+  AnthropicV2StreamEvent,
+  StreamingCompletionTransformer,
+} from "../index";
+import { parseEvent, ServerSentEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "anthropic-v2-to-openai",
+});
+
+/**
+ * Transforms an incoming Anthropic SSE (2023-06-01 API) to an equivalent
+ * OpenAI chat.completion.chunk SSE.
+ */
+export const anthropicV2ToOpenAI: StreamingCompletionTransformer = (params) => {
+  const { data } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || rawEvent.data === "[DONE]") {
+    return { position: -1 };
+  }
+
+  const completionEvent = asCompletion(rawEvent);
+  if (!completionEvent) {
+    return { position: -1 };
+  }
+
+  const newEvent = {
+    id: "ant-" + (completionEvent.log_id ?? params.fallbackId),
+    object: "chat.completion.chunk" as const,
+    created: Date.now(),
+    model: completionEvent.model ?? params.fallbackModel,
+    choices: [
+      {
+        index: 0,
+        delta: { content: completionEvent.completion },
+        finish_reason: completionEvent.stop_reason,
+      },
+    ],
+  };
+
+  return { position: completionEvent.completion.length, event: newEvent };
+};
+
+function asCompletion(event: ServerSentEvent): AnthropicV2StreamEvent | null {
+  if (event.type === "ping") return null;
+
+  try {
+    const parsed = JSON.parse(event.data);
+    if (parsed.completion !== undefined && parsed.stop_reason !== undefined) {
+      return parsed;
+    } else {
+      // noinspection ExceptionCaughtLocallyJS
+      throw new Error("Missing required fields");
+    }
+  } catch (error) {
+    log.warn({ error: error.stack, event }, "Received invalid event");
+  }
+  return null;
+}

src/proxy/middleware/response/streaming/transformers/google-ai-to-openai.ts

@@ -0,0 +1,76 @@
+import { StreamingCompletionTransformer } from "../index";
+import { parseEvent, ServerSentEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "google-ai-to-openai",
+});
+
+type GoogleAIStreamEvent = {
+  candidates: {
+    content: { parts: { text: string }[]; role: string };
+    finishReason?: "STOP" | "MAX_TOKENS" | "SAFETY" | "RECITATION" | "OTHER";
+    index: number;
+    tokenCount?: number;
+    safetyRatings: { category: string; probability: string }[];
+  }[];
+};
+
+/**
+ * Transforms an incoming Google AI SSE to an equivalent OpenAI
+ * chat.completion.chunk SSE.
+ */
+export const googleAIToOpenAI: StreamingCompletionTransformer = (params) => {
+  const { data, index } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || rawEvent.data === "[DONE]") {
+    return { position: -1 };
+  }
+
+  const completionEvent = asCompletion(rawEvent);
+  if (!completionEvent) {
+    return { position: -1 };
+  }
+
+  const parts = completionEvent.candidates[0].content.parts;
+  let content = parts[0]?.text ?? "";
+
+  // If this is the first chunk, try stripping speaker names from the response
+  // e.g. "John: Hello" -> "Hello"
+  if (index === 0) {
+    content = content.replace(/^(.*?): /, "").trim();
+  }
+
+  const newEvent = {
+    id: "goo-" + params.fallbackId,
+    object: "chat.completion.chunk" as const,
+    created: Date.now(),
+    model: params.fallbackModel,
+    choices: [
+      {
+        index: 0,
+        delta: { content },
+        finish_reason: completionEvent.candidates[0].finishReason ?? null,
+      },
+    ],
+  };
+
+  return { position: -1, event: newEvent };
+};
+
+function asCompletion(event: ServerSentEvent): GoogleAIStreamEvent | null {
+  try {
+    const parsed = JSON.parse(event.data) as GoogleAIStreamEvent;
+    if (parsed.candidates?.length > 0) {
+      return parsed;
+    } else {
+      // noinspection ExceptionCaughtLocallyJS
+      throw new Error("Missing required fields");
+    }
+  } catch (error) {
+    log.warn({ error: error.stack, event }, "Received invalid event");
+  }
+  return null;
+}

src/proxy/middleware/response/streaming/transformers/openai-text-to-openai.ts

@@ -0,0 +1,68 @@
+import { SSEResponseTransformArgs } from "../index";
+import { parseEvent, ServerSentEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "openai-text-to-openai",
+});
+
+type OpenAITextCompletionStreamEvent = {
+  id: string;
+  object: "text_completion";
+  created: number;
+  choices: {
+    text: string;
+    index: number;
+    logprobs: null;
+    finish_reason: string | null;
+  }[];
+  model: string;
+};
+
+export const openAITextToOpenAIChat = (params: SSEResponseTransformArgs) => {
+  const { data } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || rawEvent.data === "[DONE]") {
+    return { position: -1 };
+  }
+
+  const completionEvent = asCompletion(rawEvent);
+  if (!completionEvent) {
+    return { position: -1 };
+  }
+
+  const newEvent = {
+    id: completionEvent.id,
+    object: "chat.completion.chunk" as const,
+    created: completionEvent.created,
+    model: completionEvent.model,
+    choices: [
+      {
+        index: completionEvent.choices[0].index,
+        delta: { content: completionEvent.choices[0].text },
+        finish_reason: completionEvent.choices[0].finish_reason,
+      },
+    ],
+  };
+
+  return { position: -1, event: newEvent };
+};
+
+function asCompletion(
+  event: ServerSentEvent
+): OpenAITextCompletionStreamEvent | null {
+  try {
+    const parsed = JSON.parse(event.data);
+    if (Array.isArray(parsed.choices) && parsed.choices[0].text !== undefined) {
+      return parsed;
+    } else {
+      // noinspection ExceptionCaughtLocallyJS
+      throw new Error("Missing required fields");
+    }
+  } catch (error) {
+    log.warn({ error: error.stack, event }, "Received invalid data event");
+  }
+  return null;
+}

src/proxy/middleware/response/streaming/transformers/passthrough-to-openai.ts

@@ -0,0 +1,38 @@
+import {
+  OpenAIChatCompletionStreamEvent,
+  SSEResponseTransformArgs,
+} from "../index";
+import { parseEvent, ServerSentEvent } from "../parse-sse";
+import { logger } from "../../../../../logger";
+
+const log = logger.child({
+  module: "sse-transformer",
+  transformer: "openai-to-openai",
+});
+
+export const passthroughToOpenAI = (params: SSEResponseTransformArgs) => {
+  const { data } = params;
+
+  const rawEvent = parseEvent(data);
+  if (!rawEvent.data || rawEvent.data === "[DONE]") {
+    return { position: -1 };
+  }
+
+  const completionEvent = asCompletion(rawEvent);
+  if (!completionEvent) {
+    return { position: -1 };
+  }
+
+  return { position: -1, event: completionEvent };
+};
+
+function asCompletion(
+  event: ServerSentEvent
+): OpenAIChatCompletionStreamEvent | null {
+  try {
+    return JSON.parse(event.data);
+  } catch (error) {
+    log.warn({ error: error.stack, event }, "Received invalid event");
+  }
+  return null;
+}

src/proxy/mistral-ai.ts

@@ -0,0 +1,125 @@
+import { RequestHandler, Router } from "express";
+import { createProxyMiddleware } from "http-proxy-middleware";
+import { config } from "../config";
+import { keyPool } from "../shared/key-management";
+import {
+  getMistralAIModelFamily,
+  MistralAIModelFamily,
+  ModelFamily,
+} from "../shared/models";
+import { logger } from "../logger";
+import { createQueueMiddleware } from "./queue";
+import { ipLimiter } from "./rate-limit";
+import { handleProxyError } from "./middleware/common";
+import {
+  addKey,
+  createOnProxyReqHandler,
+  createPreprocessorMiddleware,
+  finalizeBody,
+} from "./middleware/request";
+import {
+  createOnProxyResHandler,
+  ProxyResHandlerWithBody,
+} from "./middleware/response";
+
+// https://docs.mistral.ai/platform/endpoints
+export const KNOWN_MISTRAL_AI_MODELS = [
+  // Mistral 7b (open weight, legacy)
+  "open-mistral-7b",
+  "mistral-tiny-2312",
+  // Mixtral 8x7b (open weight, legacy)
+  "open-mixtral-8x7b",
+  "mistral-small-2312",
+  // Mixtral Small (newer 8x7b, closed weight)
+  "mistral-small-latest",
+  "mistral-small-2402",
+  // Mistral Medium
+  "mistral-medium-latest",
+  "mistral-medium-2312",
+  // Mistral Large
+  "mistral-large-latest",
+  "mistral-large-2402",
+  // Deprecated identifiers (2024-05-01)
+  "mistral-tiny",
+  "mistral-small",
+  "mistral-medium",
+];
+
+let modelsCache: any = null;
+let modelsCacheTime = 0;
+
+export function generateModelList(models = KNOWN_MISTRAL_AI_MODELS) {
+  let available = new Set<MistralAIModelFamily>();
+  for (const key of keyPool.list()) {
+    if (key.isDisabled || key.service !== "mistral-ai") continue;
+    key.modelFamilies.forEach((family) =>
+      available.add(family as MistralAIModelFamily)
+    );
+  }
+  const allowed = new Set<ModelFamily>(config.allowedModelFamilies);
+  available = new Set([...available].filter((x) => allowed.has(x)));
+
+  return models
+    .map((id) => ({
+      id,
+      object: "model",
+      created: new Date().getTime(),
+      owned_by: "mistral-ai",
+    }))
+    .filter((model) => available.has(getMistralAIModelFamily(model.id)));
+}
+
+const handleModelRequest: RequestHandler = (_req, res) => {
+  if (new Date().getTime() - modelsCacheTime < 1000 * 60){
+    return res.status(200).json(modelsCache);
+  }
+  const result = generateModelList();
+  modelsCache = { object: "list", data: result };
+  modelsCacheTime = new Date().getTime();
+  res.status(200).json(modelsCache);
+};
+
+const mistralAIResponseHandler: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  res,
+  body
+) => {
+  if (typeof body !== "object") {
+    throw new Error("Expected body to be an object");
+  }
+
+  res.status(200).json({ ...body, proxy: body.proxy });
+};
+
+const mistralAIProxy = createQueueMiddleware({
+  proxyMiddleware: createProxyMiddleware({
+    target: "https://api.mistral.ai",
+    changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
+    on: {
+      proxyReq: createOnProxyReqHandler({
+        pipeline: [addKey, finalizeBody],
+      }),
+      proxyRes: createOnProxyResHandler([mistralAIResponseHandler]),
+      error: handleProxyError,
+    },
+  }),
+});
+
+const mistralAIRouter = Router();
+mistralAIRouter.get("/v1/models", handleModelRequest);
+// General chat completion endpoint.
+mistralAIRouter.post(
+  "/v1/chat/completions",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "mistral-ai",
+    outApi: "mistral-ai",
+    service: "mistral-ai",
+  }),
+  mistralAIProxy
+);
+
+export const mistralAI = mistralAIRouter;

src/proxy/openai-image.ts

@@ -0,0 +1,136 @@
+import { RequestHandler, Router, Request } from "express";
+import { createProxyMiddleware } from "http-proxy-middleware";
+import { config } from "../config";
+import { logger } from "../logger";
+import { createQueueMiddleware } from "./queue";
+import { ipLimiter } from "./rate-limit";
+import { handleProxyError } from "./middleware/common";
+import {
+  addKey,
+  createPreprocessorMiddleware,
+  finalizeBody,
+  createOnProxyReqHandler,
+} from "./middleware/request";
+import {
+  createOnProxyResHandler,
+  ProxyResHandlerWithBody,
+} from "./middleware/response";
+import { generateModelList } from "./openai";
+import { OpenAIImageGenerationResult } from "../shared/file-storage/mirror-generated-image";
+
+const KNOWN_MODELS = ["dall-e-2", "dall-e-3"];
+
+let modelListCache: any = null;
+let modelListValid = 0;
+const handleModelRequest: RequestHandler = (_req, res) => {
+  if (new Date().getTime() - modelListValid < 1000 * 60) {
+    return res.status(200).json(modelListCache);
+  }
+  const result = generateModelList(KNOWN_MODELS);
+  modelListCache = { object: "list", data: result };
+  modelListValid = new Date().getTime();
+  res.status(200).json(modelListCache);
+};
+
+const openaiImagesResponseHandler: ProxyResHandlerWithBody = async (
+  _proxyRes,
+  req,
+  res,
+  body
+) => {
+  if (typeof body !== "object") {
+    throw new Error("Expected body to be an object");
+  }
+
+  let newBody = body;
+  if (req.inboundApi === "openai") {
+    req.log.info("Transforming OpenAI image response to OpenAI chat format");
+    newBody = transformResponseForChat(
+      body as OpenAIImageGenerationResult,
+      req
+    );
+  }
+
+  res.status(200).json({ ...newBody, proxy: body.proxy });
+};
+
+/**
+ * Transforms a DALL-E image generation response into a chat response, simply
+ * embedding the image URL into the chat message as a Markdown image.
+ */
+function transformResponseForChat(
+  imageBody: OpenAIImageGenerationResult,
+  req: Request
+): Record<string, any> {
+  const prompt = imageBody.data[0].revised_prompt ?? req.body.prompt;
+  const content = imageBody.data
+    .map((item) => {
+      const { url, b64_json } = item;
+      if (b64_json) {
+        return `![${prompt}](data:image/png;base64,${b64_json})`;
+      } else {
+        return `![${prompt}](${url})`;
+      }
+    })
+    .join("\n\n");
+
+  return {
+    id: "dalle-" + req.id,
+    object: "chat.completion",
+    created: Date.now(),
+    model: req.body.model,
+    usage: {
+      prompt_tokens: 0,
+      completion_tokens: req.outputTokens,
+      total_tokens: req.outputTokens,
+    },
+    choices: [
+      {
+        message: { role: "assistant", content },
+        finish_reason: "stop",
+        index: 0,
+      },
+    ],
+  };
+}
+
+const openaiImagesProxy = createQueueMiddleware({
+  proxyMiddleware: createProxyMiddleware({
+    target: "https://api.openai.com",
+    changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
+    pathRewrite: {
+      "^/v1/chat/completions": "/v1/images/generations",
+    },
+    on: {
+      proxyReq: createOnProxyReqHandler({ pipeline: [addKey, finalizeBody] }),
+      proxyRes: createOnProxyResHandler([openaiImagesResponseHandler]),
+      error: handleProxyError,
+    },
+  }),
+});
+
+const openaiImagesRouter = Router();
+openaiImagesRouter.get("/v1/models", handleModelRequest);
+openaiImagesRouter.post(
+  "/v1/images/generations",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "openai-image",
+    outApi: "openai-image",
+    service: "openai",
+  }),
+  openaiImagesProxy
+);
+openaiImagesRouter.post(
+  "/v1/chat/completions",
+  ipLimiter,
+  createPreprocessorMiddleware({
+    inApi: "openai",
+    outApi: "openai-image",
+    service: "openai",
+  }),
+  openaiImagesProxy
+);
+export const openaiImage = openaiImagesRouter;

src/proxy/openai.ts

@@ -1,69 +1,74 @@
-import { RequestHandler, Request, Router } from "express";
+import { RequestHandler, Router } from "express";
-import * as http from "http";
 import { createProxyMiddleware } from "http-proxy-middleware";
 import { config } from "../config";
-import { keyPool } from "../shared/key-management";
+import { keyPool, OpenAIKey } from "../shared/key-management";
 import {
+  getOpenAIModelFamily,
   ModelFamily,
   OpenAIModelFamily,
-  getOpenAIModelFamily,
 } from "../shared/models";
 import { logger } from "../logger";
 import { createQueueMiddleware } from "./queue";
 import { ipLimiter } from "./rate-limit";
 import { handleProxyError } from "./middleware/common";
 import {
-  RequestPreprocessor,
   addKey,
-  applyQuotaLimits,
+  addKeyForEmbeddingsRequest,
-  blockZoomerOrigins,
+  createEmbeddingsPreprocessorMiddleware,
+  createOnProxyReqHandler,
   createPreprocessorMiddleware,
   finalizeBody,
-  languageFilter,
+  forceModel,
-  limitCompletions,
+  RequestPreprocessor,
-  removeOriginHeaders,
 } from "./middleware/request";
 import {
   createOnProxyResHandler,
   ProxyResHandlerWithBody,
 } from "./middleware/response";
 
+// https://platform.openai.com/docs/models/overview
+export const KNOWN_OPENAI_MODELS = [
+  "gpt-4-turbo-preview",
+  "gpt-4-0125-preview",
+  "gpt-4-1106-preview",
+  "gpt-4-vision-preview",
+  "gpt-4",
+  "gpt-4-0613",
+  "gpt-4-0314", // EOL 2024-06-13
+  "gpt-4-32k",
+  "gpt-4-32k-0314", // EOL 2024-06-13
+  "gpt-4-32k-0613",
+  "gpt-3.5-turbo",
+  "gpt-3.5-turbo-0301", // EOL 2024-06-13
+  "gpt-3.5-turbo-0613",
+  "gpt-3.5-turbo-16k",
+  "gpt-3.5-turbo-16k-0613",
+  "gpt-3.5-turbo-instruct",
+  "gpt-3.5-turbo-instruct-0914",
+  "text-embedding-ada-002",
+];
+
 let modelsCache: any = null;
 let modelsCacheTime = 0;
 
-function getModelsResponse() {
+export function generateModelList(models = KNOWN_OPENAI_MODELS) {
-  if (new Date().getTime() - modelsCacheTime < 1000 * 60) {
+  // Get available families and snapshots
-    return modelsCache;
+  let availableFamilies = new Set<OpenAIModelFamily>();
-  }
+  const availableSnapshots = new Set<string>();
-
-  // https://platform.openai.com/docs/models/overview
-  const knownModels = [
-    "gpt-4",
-    "gpt-4-0613",
-    "gpt-4-0314", // EOL 2024-06-13
-    "gpt-4-32k",
-    "gpt-4-32k-0613",
-    "gpt-4-32k-0314", // EOL 2024-06-13
-    "gpt-3.5-turbo",
-    "gpt-3.5-turbo-0301", // EOL 2024-06-13
-    "gpt-3.5-turbo-0613",
-    "gpt-3.5-turbo-16k",
-    "gpt-3.5-turbo-16k-0613",
-    "gpt-3.5-turbo-instruct",
-    "gpt-3.5-turbo-instruct-0914",
-  ];
-
-  let available = new Set<OpenAIModelFamily>();
   for (const key of keyPool.list()) {
     if (key.isDisabled || key.service !== "openai") continue;
-    key.modelFamilies.forEach((family) =>
+    const asOpenAIKey = key as OpenAIKey;
-      available.add(family as OpenAIModelFamily)
+    asOpenAIKey.modelFamilies.forEach((f) => availableFamilies.add(f));
-    );
+    asOpenAIKey.modelSnapshots.forEach((s) => availableSnapshots.add(s));
   }
-  const allowed = new Set<ModelFamily>(config.allowedModelFamilies);
-  available = new Set([...available].filter((x) => allowed.has(x)));
 
-  const models = knownModels
+  // Remove disabled families
+  const allowed = new Set<ModelFamily>(config.allowedModelFamilies);
+  availableFamilies = new Set(
+    [...availableFamilies].filter((x) => allowed.has(x))
+  );
+
+  return models
     .map((id) => ({
       id,
       object: "model",
@@ -82,16 +87,26 @@ function getModelsResponse() {
       root: id,
       parent: null,
     }))
-    .filter((model) => available.has(getOpenAIModelFamily(model.id)));
+    .filter((model) => {
+      // First check if the family is available
+      const hasFamily = availableFamilies.has(getOpenAIModelFamily(model.id));
+      if (!hasFamily) return false;
 
-  modelsCache = { object: "list", data: models };
+      // Then for snapshots, ensure the specific snapshot is available
-  modelsCacheTime = new Date().getTime();
+      const isSnapshot = model.id.match(/-\d{4}(-preview)?$/);
-
+      if (!isSnapshot) return true;
-  return modelsCache;
+      return availableSnapshots.has(model.id);
+    });
 }
 
 const handleModelRequest: RequestHandler = (_req, res) => {
-  res.status(200).json(getModelsResponse());
+  if (new Date().getTime() - modelsCacheTime < 1000 * 60) {
+    return res.status(200).json(modelsCache);
+  }
+  const result = generateModelList();
+  modelsCache = { object: "list", data: result };
+  modelsCacheTime = new Date().getTime();
+  res.status(200).json(modelsCache);
 };
 
 /** Handles some turbo-instruct special cases. */
@@ -113,31 +128,6 @@ const rewriteForTurboInstruct: RequestPreprocessor = (req) => {
   req.url = "/v1/completions";
 };
 
-const rewriteRequest = (
-  proxyReq: http.ClientRequest,
-  req: Request,
-  res: http.ServerResponse
-) => {
-  const rewriterPipeline = [
-    applyQuotaLimits,
-    addKey,
-    languageFilter,
-    limitCompletions,
-    blockZoomerOrigins,
-    removeOriginHeaders,
-    finalizeBody,
-  ];
-
-  try {
-    for (const rewriter of rewriterPipeline) {
-      rewriter(proxyReq, req, res, {});
-    }
-  } catch (error) {
-    req.log.error(error, "Error while executing proxy rewriter");
-    proxyReq.destroy(error as Error);
-  }
-};
-
 const openaiResponseHandler: ProxyResHandlerWithBody = async (
   _proxyRes,
   req,
@@ -148,22 +138,13 @@ const openaiResponseHandler: ProxyResHandlerWithBody = async (
     throw new Error("Expected body to be an object");
   }
 
-  if (config.promptLogging) {
+  let newBody = body;
-    const host = req.get("host");
-    body.proxy_note = `Prompts are logged on this proxy instance. See ${host} for more information.`;
-  }
-
   if (req.outboundApi === "openai-text" && req.inboundApi === "openai") {
     req.log.info("Transforming Turbo-Instruct response to Chat format");
-    body = transformTurboInstructResponse(body);
+    newBody = transformTurboInstructResponse(body);
   }
 
-  // TODO: Remove once tokenization is stable
+  res.status(200).json({ ...newBody, proxy: body.proxy });
-  if (req.debug) {
-    body.proxy_tokenizer_debug_info = req.debug;
-  }
-
-  res.status(200).json(body);
 };
 
 /** Only used for non-streaming responses. */
@@ -184,67 +165,76 @@ function transformTurboInstructResponse(
   return transformed;
 }
 
-const openaiProxy = createQueueMiddleware(
+const openaiProxy = createQueueMiddleware({
-  createProxyMiddleware({
+  proxyMiddleware: createProxyMiddleware({
     target: "https://api.openai.com",
     changeOrigin: true,
+    selfHandleResponse: true,
+    logger,
     on: {
-      proxyReq: rewriteRequest,
+      proxyReq: createOnProxyReqHandler({ pipeline: [addKey, finalizeBody] }),
       proxyRes: createOnProxyResHandler([openaiResponseHandler]),
       error: handleProxyError,
     },
-    selfHandleResponse: true,
+  }),
-    logger,
+});
-  })
+
-);
+const openaiEmbeddingsProxy = createProxyMiddleware({
+  target: "https://api.openai.com",
+  changeOrigin: true,
+  selfHandleResponse: false,
+  logger,
+  on: {
+    proxyReq: createOnProxyReqHandler({
+      pipeline: [addKeyForEmbeddingsRequest, finalizeBody],
+    }),
+    error: handleProxyError,
+  },
+});
 
 const openaiRouter = Router();
-// Fix paths because clients don't consistently use the /v1 prefix.
-openaiRouter.use((req, _res, next) => {
-  if (!req.path.startsWith("/v1/")) {
-    req.url = `/v1${req.url}`;
-  }
-  next();
-});
 openaiRouter.get("/v1/models", handleModelRequest);
-
 // Native text completion endpoint, only for turbo-instruct.
 openaiRouter.post(
   "/v1/completions",
   ipLimiter,
-  createPreprocessorMiddleware({ inApi: "openai-text", outApi: "openai-text" }),
+  createPreprocessorMiddleware({
+    inApi: "openai-text",
+    outApi: "openai-text",
+    service: "openai",
+  }),
   openaiProxy
 );
-
 // turbo-instruct compatibility endpoint, accepts either prompt or messages
 openaiRouter.post(
-  /\/v1\/turbo\-instruct\/(v1\/)?chat\/completions/,
+  /\/v1\/turbo-instruct\/(v1\/)?chat\/completions/,
   ipLimiter,
-  createPreprocessorMiddleware({ inApi: "openai", outApi: "openai-text" }, [
+  createPreprocessorMiddleware(
-    rewriteForTurboInstruct,
+    { inApi: "openai", outApi: "openai-text", service: "openai" },
-  ]),
+    {
+      beforeTransform: [rewriteForTurboInstruct],
+      afterTransform: [forceModel("gpt-3.5-turbo-instruct")],
+    }
+  ),
   openaiProxy
 );
-
 // General chat completion endpoint. Turbo-instruct is not supported here.
 openaiRouter.post(
   "/v1/chat/completions",
   ipLimiter,
-  createPreprocessorMiddleware({ inApi: "openai", outApi: "openai" }),
+  createPreprocessorMiddleware({
+    inApi: "openai",
+    outApi: "openai",
+    service: "openai",
+  }),
   openaiProxy
 );
-// Redirect browser requests to the homepage.
+// Embeddings endpoint.
-openaiRouter.get("*", (req, res, next) => {
+openaiRouter.post(
-  const isBrowser = req.headers["user-agent"]?.includes("Mozilla");
+  "/v1/embeddings",
-  if (isBrowser) {
+  ipLimiter,
-    res.redirect("/");
+  createEmbeddingsPreprocessorMiddleware(),
-  } else {
+  openaiEmbeddingsProxy
-    next();
+);
-  }
-});
-openaiRouter.use((req, res) => {
-  req.log.warn(`Blocked openai proxy request: ${req.method} ${req.path}`);
-  res.status(404).json({ error: "Not found" });
-});
 
 export const openai = openaiRouter;

src/proxy/palm.ts

@@ -1,207 +0,0 @@
-import { Request, RequestHandler, Router } from "express";
-import * as http from "http";
-import { createProxyMiddleware } from "http-proxy-middleware";
-import { config } from "../config";
-import { logger } from "../logger";
-import { createQueueMiddleware } from "./queue";
-import { ipLimiter } from "./rate-limit";
-import { handleProxyError } from "./middleware/common";
-import {
-  addKey,
-  applyQuotaLimits,
-  blockZoomerOrigins,
-  createPreprocessorMiddleware,
-  finalizeBody,
-  languageFilter,
-  removeOriginHeaders,
-} from "./middleware/request";
-import {
-  ProxyResHandlerWithBody,
-  createOnProxyResHandler,
-} from "./middleware/response";
-import { v4 } from "uuid";
-
-let modelsCache: any = null;
-let modelsCacheTime = 0;
-
-const getModelsResponse = () => {
-  if (new Date().getTime() - modelsCacheTime < 1000 * 60) {
-    return modelsCache;
-  }
-
-  if (!config.googlePalmKey) return { object: "list", data: [] };
-
-  const bisonVariants = ["text-bison-001"];
-
-  const models = bisonVariants.map((id) => ({
-    id,
-    object: "model",
-    created: new Date().getTime(),
-    owned_by: "google",
-    permission: [],
-    root: "palm",
-    parent: null,
-  }));
-
-  modelsCache = { object: "list", data: models };
-  modelsCacheTime = new Date().getTime();
-
-  return modelsCache;
-};
-
-const handleModelRequest: RequestHandler = (_req, res) => {
-  res.status(200).json(getModelsResponse());
-};
-
-const rewritePalmRequest = (
-  proxyReq: http.ClientRequest,
-  req: Request,
-  res: http.ServerResponse
-) => {
-  if (req.body.stream) {
-    throw new Error("Google PaLM API doesn't support streaming requests");
-  }
-
-  // PaLM API specifies the model in the URL path, not the request body. This
-  // doesn't work well with our rewriter architecture, so we need to manually
-  // fix it here.
-
-  // POST https://generativelanguage.googleapis.com/v1beta2/{model=models/*}:generateText
-  // POST https://generativelanguage.googleapis.com/v1beta2/{model=models/*}:generateMessage
-
-  // The chat api (generateMessage) is not very useful at this time as it has
-  // few params and no adjustable safety settings.
-
-  const newProxyReqPath = proxyReq.path.replace(
-    /^\/v1\/chat\/completions/,
-    `/v1beta2/models/${req.body.model}:generateText`
-  );
-  proxyReq.path = newProxyReqPath;
-
-  const rewriterPipeline = [
-    applyQuotaLimits,
-    addKey,
-    languageFilter,
-    blockZoomerOrigins,
-    removeOriginHeaders,
-    finalizeBody,
-  ];
-
-  try {
-    for (const rewriter of rewriterPipeline) {
-      rewriter(proxyReq, req, res, {});
-    }
-  } catch (error) {
-    req.log.error(error, "Error while executing proxy rewriter");
-    proxyReq.destroy(error as Error);
-  }
-};
-
-/** Only used for non-streaming requests. */
-const palmResponseHandler: ProxyResHandlerWithBody = async (
-  _proxyRes,
-  req,
-  res,
-  body
-) => {
-  if (typeof body !== "object") {
-    throw new Error("Expected body to be an object");
-  }
-
-  if (config.promptLogging) {
-    const host = req.get("host");
-    body.proxy_note = `Prompts are logged on this proxy instance. See ${host} for more information.`;
-  }
-
-  if (req.inboundApi === "openai") {
-    req.log.info("Transforming Google PaLM response to OpenAI format");
-    body = transformPalmResponse(body, req);
-  }
-
-  // TODO: Remove once tokenization is stable
-  if (req.debug) {
-    body.proxy_tokenizer_debug_info = req.debug;
-  }
-
-  // TODO: PaLM has no streaming capability which will pose a problem here if
-  // requests wait in the queue for too long.  Probably need to fake streaming
-  // and return the entire completion in one stream event using the other
-  // response handler.
-  res.status(200).json(body);
-};
-
-/**
- * Transforms a model response from the Anthropic API to match those from the
- * OpenAI API, for users using Claude via the OpenAI-compatible endpoint. This
- * is only used for non-streaming requests as streaming requests are handled
- * on-the-fly.
- */
-function transformPalmResponse(
-  palmRespBody: Record<string, any>,
-  req: Request
-): Record<string, any> {
-  const totalTokens = (req.promptTokens ?? 0) + (req.outputTokens ?? 0);
-  return {
-    id: "plm-" + v4(),
-    object: "chat.completion",
-    created: Date.now(),
-    model: req.body.model,
-    usage: {
-      prompt_tokens: req.promptTokens,
-      completion_tokens: req.outputTokens,
-      total_tokens: totalTokens,
-    },
-    choices: [
-      {
-        message: {
-          role: "assistant",
-          content: palmRespBody.candidates[0].output,
-        },
-        finish_reason: null, // palm doesn't return this
-        index: 0,
-      },
-    ],
-  };
-}
-
-const googlePalmProxy = createQueueMiddleware(
-  createProxyMiddleware({
-    target: "https://generativelanguage.googleapis.com",
-    changeOrigin: true,
-    on: {
-      proxyReq: rewritePalmRequest,
-      proxyRes: createOnProxyResHandler([palmResponseHandler]),
-      error: handleProxyError,
-    },
-    selfHandleResponse: true,
-    logger,
-  })
-);
-
-const palmRouter = Router();
-// Fix paths because clients don't consistently use the /v1 prefix.
-palmRouter.use((req, _res, next) => {
-  if (!req.path.startsWith("/v1/")) {
-    req.url = `/v1${req.url}`;
-  }
-  next();
-});
-palmRouter.get("/v1/models", handleModelRequest);
-// OpenAI-to-Google PaLM compatibility endpoint.
-palmRouter.post(
-  "/v1/chat/completions",
-  ipLimiter,
-  createPreprocessorMiddleware({ inApi: "openai", outApi: "google-palm" }),
-  googlePalmProxy
-);
-// Redirect browser requests to the homepage.
-palmRouter.get("*", (req, res, next) => {
-  const isBrowser = req.headers["user-agent"]?.includes("Mozilla");
-  if (isBrowser) {
-    res.redirect("/");
-  } else {
-    next();
-  }
-});
-
-export const googlePalm = palmRouter;

src/proxy/queue.ts

@@ -4,10 +4,6 @@
  * a given key has generated, so our queue will simply retry requests that fail
  * with a non-billing related 429 over and over again until they succeed.
  *
- * Dequeueing can operate in one of two modes:
- * - 'fair': requests are dequeued in the order they were enqueued.
- * - 'random': requests are dequeued randomly, not really a queue at all.
- *
  * When a request to a proxied endpoint is received, we create a closure around
  * the call to http-proxy-middleware and attach it to the request. This allows
  * us to pause the request until we have a key available. Further, if the
@@ -15,114 +11,118 @@
  * back in the queue and it will be retried later using the same closure.
  */
 
+import crypto from "crypto";
 import type { Handler, Request } from "express";
-import { keyPool, SupportedModel } from "../shared/key-management";
+import { BadRequestError, TooManyRequestsError } from "../shared/errors";
+import { keyPool } from "../shared/key-management";
 import {
-  getClaudeModelFamily,
+  getModelFamilyForRequest,
-  getGooglePalmModelFamily,
+  MODEL_FAMILIES,
-  getOpenAIModelFamily,
   ModelFamily,
 } from "../shared/models";
+import { initializeSseStream } from "../shared/streaming";
 import { logger } from "../logger";
-import { AGNAI_DOT_CHAT_IP } from "./rate-limit";
+import { getUniqueIps, SHARED_IP_ADDRESSES } from "./rate-limit";
-import { buildFakeSseMessage } from "./middleware/common";
+import { RequestPreprocessor } from "./middleware/request";
-import { assertNever } from "../shared/utils";
+import { handleProxyError } from "./middleware/common";
+import { sendErrorToClient } from "./middleware/response/error-generator";
 
 const queue: Request[] = [];
 const log = logger.child({ module: "request-queue" });
 
 /** Maximum number of queue slots for Agnai.chat requests. */
-const AGNAI_CONCURRENCY_LIMIT = 15;
+const AGNAI_CONCURRENCY_LIMIT = 5;
 /** Maximum number of queue slots for individual users. */
 const USER_CONCURRENCY_LIMIT = 1;
+const MIN_HEARTBEAT_SIZE = parseInt(process.env.MIN_HEARTBEAT_SIZE_B ?? "512");
+const MAX_HEARTBEAT_SIZE =
+  1024 * parseInt(process.env.MAX_HEARTBEAT_SIZE_KB ?? "1024");
+const HEARTBEAT_INTERVAL =
+  1000 * parseInt(process.env.HEARTBEAT_INTERVAL_SEC ?? "5");
+const LOAD_THRESHOLD = parseFloat(process.env.LOAD_THRESHOLD ?? "50");
+const PAYLOAD_SCALE_FACTOR = parseFloat(
+  process.env.PAYLOAD_SCALE_FACTOR ?? "6"
+);
+const QUEUE_JOIN_TIMEOUT = 5000;
 
 /**
- * Returns a unique identifier for a request. This is used to determine if a
+ * Returns an identifier for a request. This is used to determine if a
  * request is already in the queue.
+ *
  * This can be (in order of preference):
  * - user token assigned by the proxy operator
  * - x-risu-tk header, if the request is from RisuAI.xyz
+ * - 'shared-ip' if the request is from a shared IP address like Agnai.chat
  * - IP address
  */
 function getIdentifier(req: Request) {
-  if (req.user) {
+  if (req.user) return req.user.token;
-    return req.user.token;
+  if (req.risuToken) return req.risuToken;
-  }
+  if (isFromSharedIp(req)) return "shared-ip";
-  if (req.risuToken) {
-    return req.risuToken;
-  }
   return req.ip;
 }
 
-const sameUserPredicate = (incoming: Request) => (queued: Request) => {
+const sharesIdentifierWith = (incoming: Request) => (queued: Request) =>
-  const queuedId = getIdentifier(queued);
+  getIdentifier(queued) === getIdentifier(incoming);
-  const incomingId = getIdentifier(incoming);
-  return queuedId === incomingId;
-};
 
-export function enqueue(req: Request) {
+const isFromSharedIp = (req: Request) => SHARED_IP_ADDRESSES.has(req.ip);
-  const enqueuedRequestCount = queue.filter(sameUserPredicate(req)).length;
+
+export async function enqueue(req: Request) {
+  const enqueuedRequestCount = queue.filter(sharesIdentifierWith(req)).length;
   let isGuest = req.user?.token === undefined;
 
-  // All Agnai.chat requests come from the same IP, so we allow them to have
+  // Requests from shared IP addresses such as Agnai.chat are exempt from IP-
-  // more spots in the queue. Can't make it unlimited because people will
+  // based rate limiting but can only occupy a certain number of slots in the
-  // intentionally abuse it.
+  // queue. Authenticated users always get a single spot in the queue.
-  // Authenticated users always get a single spot in the queue.
+  const isSharedIp = isFromSharedIp(req);
   const maxConcurrentQueuedRequests =
-    isGuest && req.ip === AGNAI_DOT_CHAT_IP
+    isGuest && isSharedIp ? AGNAI_CONCURRENCY_LIMIT : USER_CONCURRENCY_LIMIT;
-      ? AGNAI_CONCURRENCY_LIMIT
-      : USER_CONCURRENCY_LIMIT;
   if (enqueuedRequestCount >= maxConcurrentQueuedRequests) {
-    if (req.ip === AGNAI_DOT_CHAT_IP) {
+    if (isSharedIp) {
       // Re-enqueued requests are not counted towards the limit since they
       // already made it through the queue once.
       if (req.retryCount === 0) {
-        throw new Error("Too many agnai.chat requests are already queued");
+        throw new TooManyRequestsError(
+          "Too many agnai.chat requests are already queued"
+        );
       }
     } else {
-      throw new Error("Your IP or token already has a request in the queue");
+      throw new TooManyRequestsError(
+        "Your IP or user token already has another request in the queue."
+      );
     }
   }
 
-  queue.push(req);
-  req.queueOutTime = 0;
-
   // shitty hack to remove hpm's event listeners on retried requests
   removeProxyMiddlewareEventListeners(req);
 
   // If the request opted into streaming, we need to register a heartbeat
   // handler to keep the connection alive while it waits in the queue. We
   // deregister the handler when the request is dequeued.
-  if (req.body.stream === "true" || req.body.stream === true) {
+  const { stream } = req.body;
+  if (stream === "true" || stream === true || req.isStreaming) {
     const res = req.res!;
     if (!res.headersSent) {
-      initStreaming(req);
+      await initStreaming(req);
     }
-    req.heartbeatInterval = setInterval(() => {
+    registerHeartbeat(req);
-      if (process.env.NODE_ENV === "production") {
+  } else if (getProxyLoad() > LOAD_THRESHOLD) {
-        if (!req.query.badSseParser) req.res!.write(": queue heartbeat\n\n");
+    throw new BadRequestError(
-      } else {
+      "Due to heavy traffic on this proxy, you must enable streaming in your chat client to use this endpoint."
-        req.log.info(`Sending heartbeat to request in queue.`);
+    );
-        const partition = getPartitionForRequest(req);
-        const avgWait = Math.round(getEstimatedWaitTime(partition) / 1000);
-        const currentDuration = Math.round((Date.now() - req.startTime) / 1000);
-        const debugMsg = `queue length: ${queue.length}; elapsed time: ${currentDuration}s; avg wait: ${avgWait}s`;
-        req.res!.write(buildFakeSseMessage("heartbeat", debugMsg, req));
-      }
-    }, 10000);
   }
 
-  // Register a handler to remove the request from the queue if the connection
+  queue.push(req);
-  // is aborted or closed before it is dequeued.
+  req.queueOutTime = 0;
+
   const removeFromQueue = () => {
     req.log.info(`Removing aborted request from queue.`);
     const index = queue.indexOf(req);
     if (index !== -1) {
       queue.splice(index, 1);
     }
-    if (req.heartbeatInterval) {
+    if (req.heartbeatInterval) clearInterval(req.heartbeatInterval);
-      clearInterval(req.heartbeatInterval);
+    if (req.monitorInterval) clearInterval(req.monitorInterval);
-    }
   };
   req.onAborted = removeFromQueue;
   req.res!.once("close", removeFromQueue);
@@ -130,31 +130,26 @@ export function enqueue(req: Request) {
   if (req.retryCount ?? 0 > 0) {
     req.log.info({ retries: req.retryCount }, `Enqueued request for retry.`);
   } else {
-    req.log.info(`Enqueued new request.`);
+    const size = req.socket.bytesRead;
-  }
+    const endpoint = req.url?.split("?")[0];
-}
+    req.log.info({ size, endpoint }, `Enqueued new request.`);
-
-function getPartitionForRequest(req: Request): ModelFamily {
-  // There is a single request queue, but it is partitioned by model family.
-  // Model families are typically separated on cost/rate limit boundaries so
-  // they should be treated as separate queues.
-  const provider = req.outboundApi;
-  const model = (req.body.model as SupportedModel) ?? "gpt-3.5-turbo";
-  switch (provider) {
-    case "anthropic":
-      return getClaudeModelFamily(model);
-    case "openai":
-    case "openai-text":
-      return getOpenAIModelFamily(model);
-    case "google-palm":
-      return getGooglePalmModelFamily(model);
-    default:
-      assertNever(provider);
   }
 }
 
 function getQueueForPartition(partition: ModelFamily): Request[] {
-  return queue.filter((req) => getPartitionForRequest(req) === partition);
+  return queue
+    .filter((req) => getModelFamilyForRequest(req) === partition)
+    .sort((a, b) => {
+      // Certain requests are exempted from IP-based rate limiting because they
+      // come from a shared IP address. To prevent these requests from starving
+      // out other requests during periods of high traffic, we sort them to the
+      // end of the queue.
+      const aIsExempted = isFromSharedIp(a);
+      const bIsExempted = isFromSharedIp(b);
+      if (aIsExempted && !bIsExempted) return 1;
+      if (!aIsExempted && bIsExempted) return -1;
+      return 0;
+    });
 }
 
 export function dequeue(partition: ModelFamily): Request | undefined {
@@ -174,9 +169,8 @@ export function dequeue(partition: ModelFamily): Request | undefined {
     req.onAborted = undefined;
   }
 
-  if (req.heartbeatInterval) {
+  if (req.heartbeatInterval) clearInterval(req.heartbeatInterval);
-    clearInterval(req.heartbeatInterval);
+  if (req.monitorInterval) clearInterval(req.monitorInterval);
-  }
 
   // Track the time leaving the queue now, but don't add it to the wait times
   // yet because we don't know if the request will succeed or fail. We track
@@ -195,36 +189,23 @@ export function dequeue(partition: ModelFamily): Request | undefined {
 function processQueue() {
   // This isn't completely correct, because a key can service multiple models.
   // Currently if a key is locked out on one model it will also stop servicing
-  // the others, because we only track one rate limit per key.
+  // the others, because we only track rate limits for the key as a whole.
-
-  // TODO: `getLockoutPeriod` uses model names instead of model families
-  // TODO: genericize this
-  const gpt432kLockout = keyPool.getLockoutPeriod("gpt-4-32k");
-  const gpt4Lockout = keyPool.getLockoutPeriod("gpt-4");
-  const turboLockout = keyPool.getLockoutPeriod("gpt-3.5-turbo");
-  const claudeLockout = keyPool.getLockoutPeriod("claude-v1");
-  const palmLockout = keyPool.getLockoutPeriod("text-bison-001");
 
   const reqs: (Request | undefined)[] = [];
-  if (gpt432kLockout === 0) {
+  MODEL_FAMILIES.forEach((modelFamily) => {
-    reqs.push(dequeue("gpt4-32k"));
+    const lockout = keyPool.getLockoutPeriod(modelFamily);
-  }
+    if (lockout === 0) {
-  if (gpt4Lockout === 0) {
+      reqs.push(dequeue(modelFamily));
-    reqs.push(dequeue("gpt4"));
+    }
-  }
+  });
-  if (turboLockout === 0) {
-    reqs.push(dequeue("turbo"));
-  }
-  if (claudeLockout === 0) {
-    reqs.push(dequeue("claude"));
-  }
-  if (palmLockout === 0) {
-    reqs.push(dequeue("bison"));
-  }
 
   reqs.filter(Boolean).forEach((req) => {
     if (req?.proceed) {
-      req.log.info({ retries: req.retryCount }, `Dequeuing request.`);
+      const modelFamily = getModelFamilyForRequest(req!);
+      req.log.info(
+        { retries: req.retryCount, partition: modelFamily },
+        `Dequeuing request.`
+      );
       req.proceed();
     }
   });
@@ -257,38 +238,93 @@ function cleanQueue() {
 }
 
 export function start() {
+  MODEL_FAMILIES.forEach((modelFamily) => {
+    historicalEmas.set(modelFamily, 0);
+    currentEmas.set(modelFamily, 0);
+    estimates.set(modelFamily, 0);
+  });
   processQueue();
   cleanQueue();
   log.info(`Started request queue.`);
 }
 
-let waitTimes: { partition: ModelFamily; start: number; end: number }[] = [];
+let waitTimes: {
+  partition: ModelFamily;
+  start: number;
+  end: number;
+  isDeprioritized: boolean;
+}[] = [];
 
 /** Adds a successful request to the list of wait times. */
 export function trackWaitTime(req: Request) {
   waitTimes.push({
-    partition: getPartitionForRequest(req),
+    partition: getModelFamilyForRequest(req),
     start: req.startTime!,
     end: req.queueOutTime ?? Date.now(),
+    isDeprioritized: isFromSharedIp(req),
   });
 }
 
-/** Returns average wait time in milliseconds. */
+const WAIT_TIME_INTERVAL = 3000;
-export function getEstimatedWaitTime(partition: ModelFamily) {
+const ALPHA_HISTORICAL = 0.2;
-  const now = Date.now();
+const ALPHA_CURRENT = 0.3;
-  const recentWaits = waitTimes.filter(
+const historicalEmas: Map<ModelFamily, number> = new Map();
-    (wt) => wt.partition === partition && now - wt.end < 300 * 1000
+const currentEmas: Map<ModelFamily, number> = new Map();
-  );
+const estimates: Map<ModelFamily, number> = new Map();
-  if (recentWaits.length === 0) {
-    return 0;
-  }
 
-  return (
+export function getEstimatedWaitTime(partition: ModelFamily) {
-    recentWaits.reduce((sum, wt) => sum + wt.end - wt.start, 0) /
+  return estimates.get(partition) ?? 0;
-    recentWaits.length
-  );
 }
 
+/**
+ * Returns estimated wait time for the given queue partition in milliseconds.
+ * Requests which are deprioritized are not included in the calculation as they
+ * would skew the results due to their longer wait times.
+ */
+function calculateWaitTime(partition: ModelFamily) {
+  const now = Date.now();
+  const recentWaits = waitTimes
+    .filter((wait) => {
+      const isSamePartition = wait.partition === partition;
+      const isRecent = now - wait.end < 300 * 1000;
+      const isNormalPriority = !wait.isDeprioritized;
+      return isSamePartition && isRecent && isNormalPriority;
+    })
+    .map((wait) => wait.end - wait.start);
+  const recentAverage = recentWaits.length
+    ? recentWaits.reduce((sum, wait) => sum + wait, 0) / recentWaits.length
+    : 0;
+
+  const historicalEma = historicalEmas.get(partition) ?? 0;
+  historicalEmas.set(
+    partition,
+    ALPHA_HISTORICAL * recentAverage + (1 - ALPHA_HISTORICAL) * historicalEma
+  );
+
+  const currentWaits = queue
+    .filter((req) => {
+      const isSamePartition = getModelFamilyForRequest(req) === partition;
+      const isNormalPriority = !isFromSharedIp(req);
+      return isSamePartition && isNormalPriority;
+    })
+    .map((req) => now - req.startTime!);
+  const longestCurrentWait = Math.max(...currentWaits, 0);
+
+  const currentEma = currentEmas.get(partition) ?? 0;
+  currentEmas.set(
+    partition,
+    ALPHA_CURRENT * longestCurrentWait + (1 - ALPHA_CURRENT) * currentEma
+  );
+
+  return (historicalEma + currentEma) / 2;
+}
+
+setInterval(() => {
+  MODEL_FAMILIES.forEach((modelFamily) => {
+    estimates.set(modelFamily, calculateWaitTime(modelFamily));
+  });
+}, WAIT_TIME_INTERVAL);
+
 export function getQueueLength(partition: ModelFamily | "all" = "all") {
   if (partition === "all") {
     return queue.length;
@@ -297,20 +333,47 @@ export function getQueueLength(partition: ModelFamily | "all" = "all") {
   return modelQueue.length;
 }
 
-export function createQueueMiddleware(proxyMiddleware: Handler): Handler {
+export function createQueueMiddleware({
-  return (req, res, next) => {
+  beforeProxy,
-    req.proceed = () => {
+  proxyMiddleware,
+}: {
+  beforeProxy?: RequestPreprocessor;
+  proxyMiddleware: Handler;
+}): Handler {
+  return async (req, res, next) => {
+    req.proceed = async () => {
+      if (beforeProxy) {
+        try {
+          // Hack to let us run asynchronous middleware before the
+          // http-proxy-middleware handler. This is used to sign AWS requests
+          // before they are proxied, as the signing is asynchronous.
+          // Unlike RequestPreprocessors, this runs every time the request is
+          // dequeued, not just the first time.
+          await beforeProxy(req);
+        } catch (err) {
+          return handleProxyError(err, req, res);
+        }
+      }
       proxyMiddleware(req, res, next);
     };
 
     try {
-      enqueue(req);
+      await enqueue(req);
     } catch (err: any) {
-      req.res!.status(429).json({
+      const title =
-        type: "proxy_error",
+        err.status === 429
-        message: err.message,
+          ? "Proxy queue error (too many concurrent requests)"
-        stack: err.stack,
+          : "Proxy queue error (streaming required)";
-        proxy_note: `Only one request can be queued at a time. If you don't have another request queued, your IP or user token might be in use by another request.`,
+      sendErrorToClient({
+        options: {
+          title,
+          message: err.message,
+          format: req.inboundApi,
+          reqId: req.id,
+          model: req.body?.model,
+        },
+        req,
+        res,
       });
     }
   };
@@ -319,46 +382,61 @@ export function createQueueMiddleware(proxyMiddleware: Handler): Handler {
 function killQueuedRequest(req: Request) {
   if (!req.res || req.res.writableEnded) {
     req.log.warn(`Attempted to terminate request that has already ended.`);
+    queue.splice(queue.indexOf(req), 1);
     return;
   }
   const res = req.res;
   try {
-    const message = `Your request has been terminated by the proxy because it has been in the queue for more than 5 minutes. The queue is currently ${queue.length} requests long.`;
+    const message = `Your request has been terminated by the proxy because it has been in the queue for more than 5 minutes.`;
-    if (res.headersSent) {
+    sendErrorToClient({
-      const fakeErrorEvent = buildFakeSseMessage(
+      options: {
-        "proxy queue error",
+        title: "Proxy queue error (request killed)",
         message,
-        req
+        format: req.inboundApi,
-      );
+        reqId: req.id,
-      res.write(fakeErrorEvent);
+        model: req.body?.model,
-      res.end();
+      },
-    } else {
+      req,
-      res.status(500).json({ error: message });
+      res,
-    }
+    });
   } catch (e) {
     req.log.error(e, `Error killing stalled request.`);
   }
 }
 
-function initStreaming(req: Request) {
+async function initStreaming(req: Request) {
-  req.log.info(`Initiating streaming for new queued request.`);
   const res = req.res!;
-  res.statusCode = 200;
+  initializeSseStream(res);
-  res.setHeader("Content-Type", "text/event-stream");
-  res.setHeader("Cache-Control", "no-cache");
-  res.setHeader("Connection", "keep-alive");
-  res.setHeader("X-Accel-Buffering", "no"); // nginx-specific fix
-  res.flushHeaders();
 
-  if (req.query.badSseParser) {
+  const joinMsg = `: joining queue at position ${
-    // Some clients have a broken SSE parser that doesn't handle comments
+    queue.length
-    // correctly. These clients can pass ?badSseParser=true to
+  }\n\n${getHeartbeatPayload()}`;
-    // disable comments in the SSE stream.
-    return;
-  }
 
-  res.write("\n");
+  let drainTimeout: NodeJS.Timeout;
-  res.write(": joining queue\n\n");
+  const welcome = new Promise<void>((resolve, reject) => {
+    const onDrain = () => {
+      clearTimeout(drainTimeout);
+      req.log.debug(`Client finished consuming join message.`);
+      res.off("drain", onDrain);
+      resolve();
+    };
+
+    drainTimeout = setTimeout(() => {
+      res.off("drain", onDrain);
+      res.destroy();
+      reject(new Error("Unreponsive streaming client; killing connection"));
+    }, QUEUE_JOIN_TIMEOUT);
+
+    if (!res.write(joinMsg)) {
+      req.log.warn("Kernel buffer is full; holding client request.");
+      res.once("drain", onDrain);
+    } else {
+      clearTimeout(drainTimeout);
+      resolve();
+    }
+  });
+
+  await welcome;
 }
 
 /**
@@ -414,3 +492,85 @@ function removeProxyMiddlewareEventListeners(req: Request) {
     req.removeListener("error", reqOnError as any);
   }
 }
+
+export function registerHeartbeat(req: Request) {
+  const res = req.res!;
+
+  let isBufferFull = false;
+  let bufferFullCount = 0;
+  req.heartbeatInterval = setInterval(() => {
+    if (isBufferFull) {
+      bufferFullCount++;
+      if (bufferFullCount >= 3) {
+        req.log.error("Heartbeat skipped too many times; killing connection.");
+        res.destroy();
+      } else {
+        req.log.warn({ bufferFullCount }, "Heartbeat skipped; buffer is full.");
+      }
+      return;
+    }
+
+    const data = getHeartbeatPayload();
+    if (!res.write(data)) {
+      isBufferFull = true;
+      res.once("drain", () => (isBufferFull = false));
+    }
+  }, HEARTBEAT_INTERVAL);
+  monitorHeartbeat(req);
+}
+
+function monitorHeartbeat(req: Request) {
+  const res = req.res!;
+
+  let lastBytesSent = 0;
+  req.monitorInterval = setInterval(() => {
+    const bytesSent = res.socket?.bytesWritten ?? 0;
+    const bytesSinceLast = bytesSent - lastBytesSent;
+    req.log.debug(
+      {
+        previousBytesSent: lastBytesSent,
+        currentBytesSent: bytesSent,
+      },
+      "Heartbeat monitor check."
+    );
+    lastBytesSent = bytesSent;
+
+    const minBytes = Math.floor(getHeartbeatSize() / 2);
+    if (bytesSinceLast < minBytes) {
+      req.log.warn(
+        { minBytes, bytesSinceLast },
+        "Queued request is not processing heartbeats enough data or server is overloaded; killing connection."
+      );
+      res.destroy();
+    }
+  }, HEARTBEAT_INTERVAL * 2);
+}
+
+/** Sends larger heartbeats when the queue is overloaded */
+function getHeartbeatSize() {
+  const load = getProxyLoad();
+
+  if (load <= LOAD_THRESHOLD) {
+    return MIN_HEARTBEAT_SIZE;
+  } else {
+    const excessLoad = load - LOAD_THRESHOLD;
+    const size =
+      MIN_HEARTBEAT_SIZE + Math.pow(excessLoad * PAYLOAD_SCALE_FACTOR, 2);
+    if (size > MAX_HEARTBEAT_SIZE) return MAX_HEARTBEAT_SIZE;
+    return size;
+  }
+}
+
+function getHeartbeatPayload() {
+  const size = getHeartbeatSize();
+  const data =
+    process.env.NODE_ENV === "production"
+      ? crypto.randomBytes(size).toString("base64")
+      : `payload size: ${size}`;
+
+  return `: queue heartbeat ${data}\n\n`;
+}
+
+function getProxyLoad() {
+  return Math.max(getUniqueIps(), queue.length);
+}

src/proxy/rate-limit.ts

@@ -1,23 +1,34 @@
 import { Request, Response, NextFunction } from "express";
 import { config } from "../config";
 
-export const AGNAI_DOT_CHAT_IP = "157.230.249.32";
+export const SHARED_IP_ADDRESSES = new Set([
+  // Agnai.chat
+  "157.230.249.32", // old
+  "157.245.148.56",
+  "174.138.29.50",
+  "209.97.162.44",
+]);
 
-const RATE_LIMIT_ENABLED = Boolean(config.modelRateLimit);
-const RATE_LIMIT = Math.max(1, config.modelRateLimit);
 const ONE_MINUTE_MS = 60 * 1000;
 
-const lastAttempts = new Map<string, number[]>();
+type Timestamp = number;
+/** Tracks time of last attempts from each IP address or token. */
+const lastAttempts = new Map<string, Timestamp[]>();
+/** Tracks time of exempted attempts from shared IPs like Agnai.chat. */
+const exemptedRequests: Timestamp[] = [];
 
-const expireOldAttempts = (now: number) => (attempt: number) =>
+const isRecentAttempt = (now: Timestamp) => (attempt: Timestamp) =>
   attempt > now - ONE_MINUTE_MS;
 
-const getTryAgainInMs = (ip: string) => {
+const getTryAgainInMs = (ip: string, type: "text" | "image") => {
   const now = Date.now();
   const attempts = lastAttempts.get(ip) || [];
-  const validAttempts = attempts.filter(expireOldAttempts(now));
+  const validAttempts = attempts.filter(isRecentAttempt(now));
 
-  if (validAttempts.length >= RATE_LIMIT) {
+  const limit =
+    type === "text" ? config.textModelRateLimit : config.imageModelRateLimit;
+
+  if (validAttempts.length >= limit) {
     return validAttempts[0] - now + ONE_MINUTE_MS;
   } else {
     lastAttempts.set(ip, [...validAttempts, now]);
@@ -25,21 +36,25 @@ const getTryAgainInMs = (ip: string) => {
   }
 };
 
-const getStatus = (ip: string) => {
+const getStatus = (ip: string, type: "text" | "image") => {
   const now = Date.now();
   const attempts = lastAttempts.get(ip) || [];
-  const validAttempts = attempts.filter(expireOldAttempts(now));
+  const validAttempts = attempts.filter(isRecentAttempt(now));
+
+  const limit =
+    type === "text" ? config.textModelRateLimit : config.imageModelRateLimit;
+
   return {
-    remaining: Math.max(0, RATE_LIMIT - validAttempts.length),
+    remaining: Math.max(0, limit - validAttempts.length),
     reset: validAttempts.length > 0 ? validAttempts[0] + ONE_MINUTE_MS : now,
   };
 };
 
-/** Prunes attempts and IPs that are no longer relevant after one minutes. */
+/** Prunes attempts and IPs that are no longer relevant after one minute. */
 const clearOldAttempts = () => {
   const now = Date.now();
   for (const [ip, attempts] of lastAttempts.entries()) {
-    const validAttempts = attempts.filter(expireOldAttempts(now));
+    const validAttempts = attempts.filter(isRecentAttempt(now));
     if (validAttempts.length === 0) {
       lastAttempts.delete(ip);
     } else {
@@ -49,8 +64,25 @@ const clearOldAttempts = () => {
 };
 setInterval(clearOldAttempts, 10 * 1000);
 
-export const getUniqueIps = () => {
+/** Prunes exempted requests which are older than one minute. */
-  return lastAttempts.size;
+const clearOldExemptions = () => {
+  const now = Date.now();
+  const validExemptions = exemptedRequests.filter(isRecentAttempt(now));
+  exemptedRequests.splice(0, exemptedRequests.length, ...validExemptions);
+};
+setInterval(clearOldExemptions, 10 * 1000);
+
+export const getUniqueIps = () => lastAttempts.size;
+
+/**
+ * Can be used to manually remove the most recent attempt from an IP address,
+ * ie. in case a prompt triggered OpenAI's content filter and therefore did not
+ * result in a generation.
+ */
+export const refundLastAttempt = (req: Request) => {
+  const key = req.user?.token || req.risuToken || req.ip;
+  const attempts = lastAttempts.get(key) || [];
+  attempts.pop();
 };
 
 export const ipLimiter = async (
@@ -58,37 +90,46 @@ export const ipLimiter = async (
   res: Response,
   next: NextFunction
 ) => {
-  if (!RATE_LIMIT_ENABLED) {
+  const imageLimit = config.imageModelRateLimit;
-    next();
+  const textLimit = config.textModelRateLimit;
-    return;
+
+  if (!textLimit && !imageLimit) return next();
+  if (req.user?.type === "special") return next();
+
+  // Exempts Agnai.chat from IP-based rate limiting because its IPs are shared
+  // by many users. Instead, the request queue will limit the number of such
+  // requests that may wait in the queue at a time, and sorts them to the end to
+  // let individual users go first.
+  if (SHARED_IP_ADDRESSES.has(req.ip)) {
+    exemptedRequests.push(Date.now());
+    req.log.info(
+      { ip: req.ip, recentExemptions: exemptedRequests.length },
+      "Exempting Agnai request from rate limiting."
+    );
+    return next();
   }
 
-  // Exempt Agnai.chat from rate limiting since it's shared between a lot of
+  const type = (req.baseUrl + req.path).includes("openai-image")
-  // users. Dunno how to prevent this from being abused without some sort of
+    ? "image"
-  // identifier sent from Agnaistic to identify specific users.
+    : "text";
-  if (req.ip === AGNAI_DOT_CHAT_IP) {
+  const limit = type === "image" ? imageLimit : textLimit;
-    next();
-    return;
-  }
 
   // If user is authenticated, key rate limiting by their token. Otherwise, key
   // rate limiting by their IP address. Mitigates key sharing.
   const rateLimitKey = req.user?.token || req.risuToken || req.ip;
 
-  const { remaining, reset } = getStatus(rateLimitKey);
+  const { remaining, reset } = getStatus(rateLimitKey, type);
-  res.set("X-RateLimit-Limit", config.modelRateLimit.toString());
+  res.set("X-RateLimit-Limit", limit.toString());
   res.set("X-RateLimit-Remaining", remaining.toString());
   res.set("X-RateLimit-Reset", reset.toString());
 
-  const tryAgainInMs = getTryAgainInMs(rateLimitKey);
+  const tryAgainInMs = getTryAgainInMs(rateLimitKey, type);
   if (tryAgainInMs > 0) {
     res.set("Retry-After", tryAgainInMs.toString());
     res.status(429).json({
       error: {
         type: "proxy_rate_limited",
-        message: `This proxy is rate limited to ${
+        message: `This model type is rate limited to ${limit} prompts per minute. Please try again in ${Math.ceil(
-          config.modelRateLimit
-        } prompts per minute. Please try again in ${Math.ceil(
           tryAgainInMs / 1000
         )} seconds.`,
       },

src/proxy/routes.ts

@@ -1,20 +1,27 @@
-/* Accepts incoming requests at either the /kobold or /openai routes and then
+import express, { Request, Response, NextFunction } from "express";
-routes them to the appropriate handler to be forwarded to the OpenAI API.
-Incoming OpenAI requests are more or less 1:1 with the OpenAI API, but only a
-subset of the API is supported. Kobold requests must be transformed into
-equivalent OpenAI requests. */
-
-import * as express from "express";
 import { gatekeeper } from "./gatekeeper";
 import { checkRisuToken } from "./check-risu-token";
 import { openai } from "./openai";
+import { openaiImage } from "./openai-image";
 import { anthropic } from "./anthropic";
-import { googlePalm } from "./palm";
+import { googleAI } from "./google-ai";
+import { mistralAI } from "./mistral-ai";
+import { aws } from "./aws";
+import { azure } from "./azure";
+import { sendErrorToClient } from "./middleware/response/error-generator";
 
 const proxyRouter = express.Router();
+proxyRouter.use((req, _res, next) => {
+  if (req.headers.expect) {
+    // node-http-proxy does not like it when clients send `expect: 100-continue`
+    // and will stall. none of the upstream APIs use this header anyway.
+    delete req.headers.expect;
+  }
+  next();
+});
 proxyRouter.use(
-  express.json({ limit: "1536kb" }),
+  express.json({ limit: "100mb" }),
-  express.urlencoded({ extended: true, limit: "1536kb" })
+  express.urlencoded({ extended: true, limit: "100mb" })
 );
 proxyRouter.use(gatekeeper);
 proxyRouter.use(checkRisuToken);
@@ -23,7 +30,48 @@ proxyRouter.use((req, _res, next) => {
   req.retryCount = 0;
   next();
 });
-proxyRouter.use("/openai", openai);
+proxyRouter.use("/openai", addV1, openai);
-proxyRouter.use("/anthropic", anthropic);
+proxyRouter.use("/openai-image", addV1, openaiImage);
-proxyRouter.use("/google-palm", googlePalm);
+proxyRouter.use("/anthropic", addV1, anthropic);
+proxyRouter.use("/google-ai", addV1, googleAI);
+proxyRouter.use("/mistral-ai", addV1, mistralAI);
+proxyRouter.use("/aws/claude", addV1, aws);
+proxyRouter.use("/azure/openai", addV1, azure);
+// Redirect browser requests to the homepage.
+proxyRouter.get("*", (req, res, next) => {
+  const isBrowser = req.headers["user-agent"]?.includes("Mozilla");
+  if (isBrowser) {
+    res.redirect("/");
+  } else {
+    next();
+  }
+});
+// Handle 404s.
+proxyRouter.use((req, res) => {
+  sendErrorToClient({
+    req,
+    res,
+    options: {
+      title: "Proxy error (HTTP 404 Not Found)",
+      message: "The requested proxy endpoint does not exist.",
+      model: req.body?.model,
+      reqId: req.id,
+      format: "unknown",
+      obj: {
+        proxy_note:
+          "Your chat client is using the wrong endpoint. Check the Service Info page for the list of available endpoints.",
+        requested_url: req.originalUrl,
+      },
+    },
+  });
+});
+
 export { proxyRouter as proxyRouter };
+
+function addV1(req: Request, res: Response, next: NextFunction) {
+  // Clients don't consistently use the /v1 prefix so we'll add it for them.
+  if (!req.path.startsWith("/v1/")) {
+    req.url = `/v1${req.url}`;
+  }
+  next();
+}

src/server.ts

@@ -1,23 +1,29 @@
-import { assertConfigIsValid, config } from "./config";
+import { assertConfigIsValid, config, USER_ASSETS_DIR } from "./config";
 import "source-map-support/register";
+import checkDiskSpace from "check-disk-space";
 import express from "express";
 import cors from "cors";
 import path from "path";
 import pinoHttp from "pino-http";
+import os from "os";
 import childProcess from "child_process";
 import { logger } from "./logger";
+import { setupAssetsDir } from "./shared/file-storage/setup-assets-dir";
 import { keyPool } from "./shared/key-management";
 import { adminRouter } from "./admin/routes";
 import { proxyRouter } from "./proxy/routes";
-import { handleInfoPage } from "./info-page";
+import { infoPageRouter } from "./info-page";
+import { IMAGE_GEN_MODELS } from "./shared/models";
+import { userRouter } from "./user/routes";
 import { logQueue } from "./shared/prompt-logging";
 import { start as startRequestQueue } from "./proxy/queue";
 import { init as initUserStore } from "./shared/users/user-store";
 import { init as initTokenizers } from "./shared/tokenization";
 import { checkOrigin } from "./proxy/check-origin";
-import { userRouter } from "./user/routes";
+import { sendErrorToClient } from "./proxy/middleware/response/error-generator";
 
 const PORT = config.port;
+const BIND_ADDRESS = config.bindAddress;
 
 const app = express();
 // middleware
@@ -25,12 +31,7 @@ app.use(
   pinoHttp({
     quietReqLogger: true,
     logger,
-    autoLogging: {
+    autoLogging: { ignore: ({ url }) => ["/health"].includes(url as string) },
-      ignore: (req) => {
-        const ignored = ["/proxy/kobold/api/v1/model", "/health"];
-        return ignored.includes(req.url as string);
-      },
-    },
     redact: {
       paths: [
         "req.headers.cookie",
@@ -43,13 +44,15 @@ app.use(
       ],
       censor: "********",
     },
+    customProps: (req) => {
+      const user = (req as express.Request).user;
+      if (user) return { userToken: `...${user.token.slice(-5)}` };
+      return {};
+    },
   })
 );
 
-// TODO: Detect (or support manual configuration of) whether the app is behind
+app.set("trust proxy", Number(config.trustedProxies));
-// a load balancer/reverse proxy, which is necessary to determine request IP
-// addresses correctly.
-app.set("trust proxy", true);
 
 app.set("view engine", "ejs");
 app.set("views", [
@@ -58,32 +61,42 @@ app.set("views", [
   path.join(__dirname, "shared/views"),
 ]);
 
+app.use("/user_content", express.static(USER_ASSETS_DIR, { maxAge: "2h" }));
+
 app.get("/health", (_req, res) => res.sendStatus(200));
 app.use(cors());
 app.use(checkOrigin);
 
-// routes
-app.get("/", handleInfoPage);
 app.use("/admin", adminRouter);
-app.use("/proxy", proxyRouter);
+app.use(config.proxyEndpointRoute, proxyRouter);
 app.use("/user", userRouter);
+if (config.staticServiceInfo) {
+  app.get("/", (_req, res) => res.sendStatus(200));
+} else {
+  app.use("/", infoPageRouter);
+}
 
-// 500 and 404
+app.use(
-app.use((err: any, _req: unknown, res: express.Response, _next: unknown) => {
+  (err: any, req: express.Request, res: express.Response, _next: unknown) => {
-  if (err.status) {
+    if (!err.status) {
-    res.status(err.status).json({ error: err.message });
+      logger.error(err, "Unhandled error in request");
-  } else {
+    }
-    logger.error(err);
+
-    res.status(500).json({
+    sendErrorToClient({
-      error: {
+      req,
-        type: "proxy_error",
+      res,
-        message: err.message,
+      options: {
-        stack: err.stack,
+        title: `Proxy error (HTTP ${err.status})`,
-        proxy_note: `Reverse proxy encountered an internal server error.`,
+        message:
+          "Reverse proxy encountered an unexpected error while processing your request.",
+        reqId: req.id,
+        statusCode: err.status,
+        obj: { error: err.message, stack: err.stack },
+        format: "unknown",
       },
     });
   }
-});
+);
 app.use((_req: unknown, res: express.Response) => {
   res.status(404).json({ error: "Not found" });
 });
@@ -99,25 +112,36 @@ async function start() {
 
   await initTokenizers();
 
+  if (config.allowedModelFamilies.some((f) => IMAGE_GEN_MODELS.includes(f))) {
+    await setupAssetsDir();
+  }
+
   if (config.gatekeeper === "user_token") {
     await initUserStore();
   }
 
   if (config.promptLogging) {
     logger.info("Starting prompt logging...");
-    logQueue.start();
+    await logQueue.start();
   }
 
   logger.info("Starting request queue...");
   startRequestQueue();
 
-  app.listen(PORT, async () => {
+  const diskSpace = await checkDiskSpace(
-    logger.info({ port: PORT }, "Now listening for connections.");
+    __dirname.startsWith("/app") ? "/app" : os.homedir()
+  );
+
+  app.listen(PORT, BIND_ADDRESS, () => {
+    logger.info(
+      { port: PORT, interface: BIND_ADDRESS },
+      "Now listening for connections."
+    );
     registerUncaughtExceptionHandler();
   });
 
   logger.info(
-    { build: process.env.BUILD_INFO, nodeEnv: process.env.NODE_ENV },
+    { build: process.env.BUILD_INFO, nodeEnv: process.env.NODE_ENV, diskSpace },
     "Startup complete."
   );
 }
@@ -145,7 +169,18 @@ function registerUncaughtExceptionHandler() {
  * didn't set it to something misleading.
  */
 async function setBuildInfo() {
-  // Render .dockerignore's the .git directory but provides info in the env
+  // For CI builds, use the env vars set during the build process
+  if (process.env.GITGUD_BRANCH) {
+    const sha = process.env.GITGUD_COMMIT?.slice(0, 7) || "unknown SHA";
+    const branch = process.env.GITGUD_BRANCH;
+    const repo = process.env.GITGUD_PROJECT;
+    const buildInfo = `[ci] ${sha} (${branch}@${repo})`;
+    process.env.BUILD_INFO = buildInfo;
+    logger.info({ build: buildInfo }, "Using build info from CI image.");
+    return;
+  }
+
+  // For render, the git directory is dockerignore'd so we use env vars
   if (process.env.RENDER) {
     const sha = process.env.RENDER_GIT_COMMIT?.slice(0, 7) || "unknown SHA";
     const branch = process.env.RENDER_GIT_BRANCH || "unknown branch";
@@ -156,10 +191,10 @@ async function setBuildInfo() {
     return;
   }
 
+  // For huggingface and bare metal deployments, we can get the info from git
   try {
-    // Ignore git's complaints about dubious directory ownership on Huggingface
-    // (which evidently runs dockerized Spaces on Windows with weird NTFS perms)
     if (process.env.SPACE_ID) {
+      // TODO: may not be necessary anymore with adjusted Huggingface dockerfile
       childProcess.execSync("git config --global --add safe.directory /app");
     }
 
@@ -179,7 +214,7 @@ async function setBuildInfo() {
 
     let [sha, branch, remote, status] = await Promise.all(promises);
 
-    remote = remote.match(/.*[\/:]([\w-]+)\/([\w\-\.]+?)(?:\.git)?$/) || [];
+    remote = remote.match(/.*[\/:]([\w-]+)\/([\w\-.]+?)(?:\.git)?$/) || [];
     const repo = remote.slice(-2).join("/");
     status = status
       // ignore Dockerfile changes since that's how the user deploys the app

src/service-info.ts

@@ -0,0 +1,476 @@
+import { config, listConfig } from "./config";
+import {
+  AnthropicKey,
+  AwsBedrockKey,
+  AzureOpenAIKey,
+  GoogleAIKey,
+  keyPool,
+  OpenAIKey,
+} from "./shared/key-management";
+import {
+  AnthropicModelFamily,
+  assertIsKnownModelFamily,
+  AwsBedrockModelFamily,
+  AzureOpenAIModelFamily,
+  GoogleAIModelFamily,
+  LLM_SERVICES,
+  LLMService,
+  MistralAIModelFamily,
+  MODEL_FAMILY_SERVICE,
+  ModelFamily,
+  OpenAIModelFamily,
+} from "./shared/models";
+import { getCostSuffix, getTokenCostUsd, prettyTokens } from "./shared/stats";
+import { getUniqueIps } from "./proxy/rate-limit";
+import { assertNever } from "./shared/utils";
+import { getEstimatedWaitTime, getQueueLength } from "./proxy/queue";
+import { MistralAIKey } from "./shared/key-management/mistral-ai/provider";
+
+const CACHE_TTL = 2000;
+
+type KeyPoolKey = ReturnType<typeof keyPool.list>[0];
+const keyIsOpenAIKey = (k: KeyPoolKey): k is OpenAIKey =>
+  k.service === "openai";
+const keyIsAzureKey = (k: KeyPoolKey): k is AzureOpenAIKey =>
+  k.service === "azure";
+const keyIsAnthropicKey = (k: KeyPoolKey): k is AnthropicKey =>
+  k.service === "anthropic";
+const keyIsGoogleAIKey = (k: KeyPoolKey): k is GoogleAIKey =>
+  k.service === "google-ai";
+const keyIsMistralAIKey = (k: KeyPoolKey): k is MistralAIKey =>
+  k.service === "mistral-ai";
+const keyIsAwsKey = (k: KeyPoolKey): k is AwsBedrockKey => k.service === "aws";
+
+/** Stats aggregated across all keys for a given service. */
+type ServiceAggregate = "keys" | "uncheckedKeys" | "orgs";
+/** Stats aggregated across all keys for a given model family. */
+type ModelAggregates = {
+  active: number;
+  trial?: number;
+  revoked?: number;
+  overQuota?: number;
+  pozzed?: number;
+  awsLogged?: number;
+  awsSonnet?: number;
+  awsHaiku?: number;
+  queued: number;
+  queueTime: string;
+  tokens: number;
+};
+/** All possible combinations of model family and aggregate type. */
+type ModelAggregateKey = `${ModelFamily}__${keyof ModelAggregates}`;
+
+type AllStats = {
+  proompts: number;
+  tokens: number;
+  tokenCost: number;
+} & { [modelFamily in ModelFamily]?: ModelAggregates } & {
+  [service in LLMService as `${service}__${ServiceAggregate}`]?: number;
+};
+
+type BaseFamilyInfo = {
+  usage?: string;
+  activeKeys: number;
+  revokedKeys?: number;
+  proomptersInQueue?: number;
+  estimatedQueueTime?: string;
+};
+type OpenAIInfo = BaseFamilyInfo & {
+  trialKeys?: number;
+  overQuotaKeys?: number;
+};
+type AnthropicInfo = BaseFamilyInfo & {
+  prefilledKeys?: number;
+  overQuotaKeys?: number;
+};
+type AwsInfo = BaseFamilyInfo & {
+  privacy?: string;
+  sonnetKeys?: number;
+  haikuKeys?: number;
+};
+
+// prettier-ignore
+export type ServiceInfo = {
+  uptime: number;
+  endpoints: {
+    openai?: string;
+    openai2?: string;
+    anthropic?: string;
+    "anthropic-claude-3"?: string;
+    "google-ai"?: string;
+    "mistral-ai"?: string;
+    aws?: string;
+    azure?: string;
+    "openai-image"?: string;
+    "azure-image"?: string;
+  };
+  proompts?: number;
+  tookens?: string;
+  proomptersNow?: number;
+  status?: string;
+  config: ReturnType<typeof listConfig>;
+  build: string;
+} & { [f in OpenAIModelFamily]?: OpenAIInfo }
+  & { [f in AnthropicModelFamily]?: AnthropicInfo; }
+  & { [f in AwsBedrockModelFamily]?: AwsInfo }
+  & { [f in AzureOpenAIModelFamily]?: BaseFamilyInfo; }
+  & { [f in GoogleAIModelFamily]?: BaseFamilyInfo }
+  & { [f in MistralAIModelFamily]?: BaseFamilyInfo };
+
+// https://stackoverflow.com/a/66661477
+// type DeepKeyOf<T> = (
+//   [T] extends [never]
+//     ? ""
+//     : T extends object
+//     ? {
+//         [K in Exclude<keyof T, symbol>]: `${K}${DotPrefix<DeepKeyOf<T[K]>>}`;
+//       }[Exclude<keyof T, symbol>]
+//     : ""
+// ) extends infer D
+//   ? Extract<D, string>
+//   : never;
+// type DotPrefix<T extends string> = T extends "" ? "" : `.${T}`;
+// type ServiceInfoPath = `{${DeepKeyOf<ServiceInfo>}}`;
+
+const SERVICE_ENDPOINTS: { [s in LLMService]: Record<string, string> } = {
+  openai: {
+    openai: `%BASE%/openai`,
+    openai2: `%BASE%/openai/turbo-instruct`,
+    "openai-image": `%BASE%/openai-image`,
+  },
+  anthropic: {
+    anthropic: `%BASE%/anthropic`,
+    "anthropic-sonnet (⚠️Temporary: for Claude 3 Sonnet)": `%BASE%/anthropic/sonnet`,
+    "anthropic-opus (⚠️Temporary: for Claude 3 Opus)": `%BASE%/anthropic/opus`,
+  },
+  "google-ai": {
+    "google-ai": `%BASE%/google-ai`,
+  },
+  "mistral-ai": {
+    "mistral-ai": `%BASE%/mistral-ai`,
+  },
+  aws: {
+    aws: `%BASE%/aws/claude`,
+    "aws-sonnet (⚠️Temporary: for AWS Claude 3 Sonnet)": `%BASE%/aws/claude/sonnet`,
+  },
+  azure: {
+    azure: `%BASE%/azure/openai`,
+    "azure-image": `%BASE%/azure/openai`,
+  },
+};
+
+const modelStats = new Map<ModelAggregateKey, number>();
+const serviceStats = new Map<keyof AllStats, number>();
+
+let cachedInfo: ServiceInfo | undefined;
+let cacheTime = 0;
+
+export function buildInfo(baseUrl: string, forAdmin = false): ServiceInfo {
+  if (cacheTime + CACHE_TTL > Date.now()) return cachedInfo!;
+
+  const keys = keyPool.list();
+  const accessibleFamilies = new Set(
+    keys
+      .flatMap((k) => k.modelFamilies)
+      .filter((f) => config.allowedModelFamilies.includes(f))
+      .concat("turbo")
+  );
+
+  modelStats.clear();
+  serviceStats.clear();
+  keys.forEach(addKeyToAggregates);
+
+  const endpoints = getEndpoints(baseUrl, accessibleFamilies);
+  const trafficStats = getTrafficStats();
+  const { serviceInfo, modelFamilyInfo } =
+    getServiceModelStats(accessibleFamilies);
+  const status = getStatus();
+
+  if (config.staticServiceInfo && !forAdmin) {
+    delete trafficStats.proompts;
+    delete trafficStats.tookens;
+    delete trafficStats.proomptersNow;
+    for (const family of Object.keys(modelFamilyInfo)) {
+      assertIsKnownModelFamily(family);
+      delete modelFamilyInfo[family]?.proomptersInQueue;
+      delete modelFamilyInfo[family]?.estimatedQueueTime;
+      delete modelFamilyInfo[family]?.usage;
+    }
+  }
+
+  return (cachedInfo = {
+    uptime: Math.floor(process.uptime()),
+    endpoints,
+    ...trafficStats,
+    ...serviceInfo,
+    status,
+    ...modelFamilyInfo,
+    config: listConfig(),
+    build: process.env.BUILD_INFO || "dev",
+  });
+}
+
+function getStatus() {
+  if (!config.checkKeys) return "Key checking is disabled.";
+
+  let unchecked = 0;
+  for (const service of LLM_SERVICES) {
+    unchecked += serviceStats.get(`${service}__uncheckedKeys`) || 0;
+  }
+
+  return unchecked ? `Checking ${unchecked} keys...` : undefined;
+}
+
+function getEndpoints(baseUrl: string, accessibleFamilies: Set<ModelFamily>) {
+  const endpoints: Record<string, string> = {};
+  const keys = keyPool.list();
+  for (const service of LLM_SERVICES) {
+    if (!keys.some((k) => k.service === service)) {
+      continue;
+    }
+
+    for (const [name, url] of Object.entries(SERVICE_ENDPOINTS[service])) {
+      endpoints[name] = url.replace("%BASE%", baseUrl);
+    }
+
+    if (service === "openai" && !accessibleFamilies.has("dall-e")) {
+      delete endpoints["openai-image"];
+    }
+
+    if (service === "azure" && !accessibleFamilies.has("azure-dall-e")) {
+      delete endpoints["azure-image"];
+    }
+  }
+  return endpoints;
+}
+
+type TrafficStats = Pick<ServiceInfo, "proompts" | "tookens" | "proomptersNow">;
+
+function getTrafficStats(): TrafficStats {
+  const tokens = serviceStats.get("tokens") || 0;
+  const tokenCost = serviceStats.get("tokenCost") || 0;
+  return {
+    proompts: serviceStats.get("proompts") || 0,
+    tookens: `${prettyTokens(tokens)}${getCostSuffix(tokenCost)}`,
+    ...(config.textModelRateLimit ? { proomptersNow: getUniqueIps() } : {}),
+  };
+}
+
+function getServiceModelStats(accessibleFamilies: Set<ModelFamily>) {
+  const serviceInfo: {
+    [s in LLMService as `${s}${"Keys" | "Orgs"}`]?: number;
+  } = {};
+  const modelFamilyInfo: { [f in ModelFamily]?: BaseFamilyInfo } = {};
+
+  for (const service of LLM_SERVICES) {
+    const hasKeys = serviceStats.get(`${service}__keys`) || 0;
+    if (!hasKeys) continue;
+
+    serviceInfo[`${service}Keys`] = hasKeys;
+    accessibleFamilies.forEach((f) => {
+      if (MODEL_FAMILY_SERVICE[f] === service) {
+        modelFamilyInfo[f] = getInfoForFamily(f);
+      }
+    });
+
+    if (service === "openai" && config.checkKeys) {
+      serviceInfo.openaiOrgs = getUniqueOpenAIOrgs(keyPool.list());
+    }
+  }
+  return { serviceInfo, modelFamilyInfo };
+}
+
+function getUniqueOpenAIOrgs(keys: KeyPoolKey[]) {
+  const orgIds = new Set(
+    keys.filter((k) => k.service === "openai").map((k: any) => k.organizationId)
+  );
+  return orgIds.size;
+}
+
+function increment<T extends keyof AllStats | ModelAggregateKey>(
+  map: Map<T, number>,
+  key: T,
+  delta = 1
+) {
+  map.set(key, (map.get(key) || 0) + delta);
+}
+
+function addKeyToAggregates(k: KeyPoolKey) {
+  increment(serviceStats, "proompts", k.promptCount);
+  increment(serviceStats, "openai__keys", k.service === "openai" ? 1 : 0);
+  increment(serviceStats, "anthropic__keys", k.service === "anthropic" ? 1 : 0);
+  increment(serviceStats, "google-ai__keys", k.service === "google-ai" ? 1 : 0);
+  increment(
+    serviceStats,
+    "mistral-ai__keys",
+    k.service === "mistral-ai" ? 1 : 0
+  );
+  increment(serviceStats, "aws__keys", k.service === "aws" ? 1 : 0);
+  increment(serviceStats, "azure__keys", k.service === "azure" ? 1 : 0);
+
+  let sumTokens = 0;
+  let sumCost = 0;
+
+  switch (k.service) {
+    case "openai":
+      if (!keyIsOpenAIKey(k)) throw new Error("Invalid key type");
+      increment(
+        serviceStats,
+        "openai__uncheckedKeys",
+        Boolean(k.lastChecked) ? 0 : 1
+      );
+
+      k.modelFamilies.forEach((f) => {
+        const tokens = k[`${f}Tokens`];
+        sumTokens += tokens;
+        sumCost += getTokenCostUsd(f, tokens);
+        increment(modelStats, `${f}__tokens`, tokens);
+        increment(modelStats, `${f}__revoked`, k.isRevoked ? 1 : 0);
+        increment(modelStats, `${f}__active`, k.isDisabled ? 0 : 1);
+        increment(modelStats, `${f}__trial`, k.isTrial ? 1 : 0);
+        increment(modelStats, `${f}__overQuota`, k.isOverQuota ? 1 : 0);
+      });
+      break;
+    case "azure":
+      if (!keyIsAzureKey(k)) throw new Error("Invalid key type");
+      k.modelFamilies.forEach((f) => {
+        const tokens = k[`${f}Tokens`];
+        sumTokens += tokens;
+        sumCost += getTokenCostUsd(f, tokens);
+        increment(modelStats, `${f}__tokens`, tokens);
+        increment(modelStats, `${f}__active`, k.isDisabled ? 0 : 1);
+        increment(modelStats, `${f}__revoked`, k.isRevoked ? 1 : 0);
+      });
+      break;
+    case "anthropic": {
+      if (!keyIsAnthropicKey(k)) throw new Error("Invalid key type");
+      k.modelFamilies.forEach((f) => {
+        const tokens = k[`${f}Tokens`];
+        sumTokens += tokens;
+        sumCost += getTokenCostUsd(f, tokens);
+        increment(modelStats, `${f}__tokens`, tokens);
+        increment(modelStats, `${f}__revoked`, k.isRevoked ? 1 : 0);
+        increment(modelStats, `${f}__active`, k.isDisabled ? 0 : 1);
+        increment(modelStats, `${f}__overQuota`, k.isOverQuota ? 1 : 0);
+        increment(modelStats, `${f}__pozzed`, k.isPozzed ? 1 : 0);
+      });
+      increment(
+        serviceStats,
+        "anthropic__uncheckedKeys",
+        Boolean(k.lastChecked) ? 0 : 1
+      );
+      break;
+    }
+    case "google-ai": {
+      if (!keyIsGoogleAIKey(k)) throw new Error("Invalid key type");
+      const family = "gemini-pro";
+      sumTokens += k["gemini-proTokens"];
+      sumCost += getTokenCostUsd(family, k["gemini-proTokens"]);
+      increment(modelStats, `${family}__active`, k.isDisabled ? 0 : 1);
+      increment(modelStats, `${family}__revoked`, k.isRevoked ? 1 : 0);
+      increment(modelStats, `${family}__tokens`, k["gemini-proTokens"]);
+      break;
+    }
+    case "mistral-ai": {
+      if (!keyIsMistralAIKey(k)) throw new Error("Invalid key type");
+      k.modelFamilies.forEach((f) => {
+        const tokens = k[`${f}Tokens`];
+        sumTokens += tokens;
+        sumCost += getTokenCostUsd(f, tokens);
+        increment(modelStats, `${f}__tokens`, tokens);
+        increment(modelStats, `${f}__revoked`, k.isRevoked ? 1 : 0);
+        increment(modelStats, `${f}__active`, k.isDisabled ? 0 : 1);
+      });
+      break;
+    }
+    case "aws": {
+      if (!keyIsAwsKey(k)) throw new Error("Invalid key type");
+      const family = "aws-claude";
+      sumTokens += k["aws-claudeTokens"];
+      sumCost += getTokenCostUsd(family, k["aws-claudeTokens"]);
+      increment(modelStats, `${family}__active`, k.isDisabled ? 0 : 1);
+      increment(modelStats, `${family}__revoked`, k.isRevoked ? 1 : 0);
+      increment(modelStats, `${family}__tokens`, k["aws-claudeTokens"]);
+      increment(modelStats, `${family}__awsSonnet`, k.sonnetEnabled ? 1 : 0);
+      increment(modelStats, `${family}__awsHaiku`, k.haikuEnabled ? 1 : 0);
+
+      // Ignore revoked keys for aws logging stats, but include keys where the
+      // logging status is unknown.
+      const countAsLogged =
+        k.lastChecked && !k.isDisabled && k.awsLoggingStatus !== "disabled";
+      increment(modelStats, `${family}__awsLogged`, countAsLogged ? 1 : 0);
+
+      break;
+    }
+    default:
+      assertNever(k.service);
+  }
+
+  increment(serviceStats, "tokens", sumTokens);
+  increment(serviceStats, "tokenCost", sumCost);
+}
+
+function getInfoForFamily(family: ModelFamily): BaseFamilyInfo {
+  const tokens = modelStats.get(`${family}__tokens`) || 0;
+  const cost = getTokenCostUsd(family, tokens);
+  let info: BaseFamilyInfo & OpenAIInfo & AnthropicInfo & AwsInfo = {
+    usage: `${prettyTokens(tokens)} tokens${getCostSuffix(cost)}`,
+    activeKeys: modelStats.get(`${family}__active`) || 0,
+    revokedKeys: modelStats.get(`${family}__revoked`) || 0,
+  };
+
+  // Add service-specific stats to the info object.
+  if (config.checkKeys) {
+    const service = MODEL_FAMILY_SERVICE[family];
+    switch (service) {
+      case "openai":
+        info.overQuotaKeys = modelStats.get(`${family}__overQuota`) || 0;
+        info.trialKeys = modelStats.get(`${family}__trial`) || 0;
+
+        // Delete trial/revoked keys for non-turbo families.
+        // Trials are turbo 99% of the time, and if a key is invalid we don't
+        // know what models it might have had assigned to it.
+        if (family !== "turbo") {
+          delete info.trialKeys;
+          delete info.revokedKeys;
+        }
+        break;
+      case "anthropic":
+        info.overQuotaKeys = modelStats.get(`${family}__overQuota`) || 0;
+        info.prefilledKeys = modelStats.get(`${family}__pozzed`) || 0;
+        break;
+      case "aws":
+        info.sonnetKeys = modelStats.get(`${family}__awsSonnet`) || 0;
+        info.haikuKeys = modelStats.get(`${family}__awsHaiku`) || 0;
+        const logged = modelStats.get(`${family}__awsLogged`) || 0;
+        if (logged > 0) {
+          info.privacy = config.allowAwsLogging
+            ? `${logged} active keys are potentially logged.`
+            : `${logged} active keys are potentially logged and can't be used. Set ALLOW_AWS_LOGGING=true to override.`;
+        }
+        break;
+    }
+  }
+
+  // Add queue stats to the info object.
+  const queue = getQueueInformation(family);
+  info.proomptersInQueue = queue.proomptersInQueue;
+  info.estimatedQueueTime = queue.estimatedQueueTime;
+
+  return info;
+}
+
+/** Returns queue time in seconds, or minutes + seconds if over 60 seconds. */
+function getQueueInformation(partition: ModelFamily) {
+  const waitMs = getEstimatedWaitTime(partition);
+  const waitTime =
+    waitMs < 60000
+      ? `${Math.round(waitMs / 1000)}sec`
+      : `${Math.round(waitMs / 60000)}min, ${Math.round(
+          (waitMs % 60000) / 1000
+        )}sec`;
+  return {
+    proomptersInQueue: getQueueLength(partition),
+    estimatedQueueTime: waitMs > 2000 ? waitTime : "no wait",
+  };
+}

src/shared/api-support/index.ts

@@ -0,0 +1,84 @@
+import type { Request, Response } from "express";
+import { z } from "zod";
+import { APIFormat } from "../key-management";
+import { AnthropicV1MessagesSchema } from "./kits/anthropic-chat/schema";
+import { AnthropicV1TextSchema } from "./kits/anthropic-text/schema";
+import { transformOpenAIToAnthropicText } from "./kits/anthropic-text/request-transformers";
+import {
+  transformAnthropicTextToAnthropicChat,
+  transformOpenAIToAnthropicChat,
+} from "./kits/anthropic-chat/request-transformers";
+import { GoogleAIV1GenerateContentSchema } from "./kits/google-ai/schema";
+import { transformOpenAIToGoogleAI } from "./kits/google-ai/request-transformers";
+import { MistralAIV1ChatCompletionsSchema } from "./kits/mistral-ai/schema";
+
+import { OpenAIV1ChatCompletionSchema } from "./kits/openai/schema";
+import { OpenAIV1ImagesGenerationSchema } from "./kits/openai-image/schema";
+import { transformOpenAIToOpenAIImage } from "./kits/openai-image/request-transformers";
+import { OpenAIV1TextCompletionSchema } from "./kits/openai-text/schema";
+import { transformOpenAIToOpenAIText } from "./kits/openai-text/request-transformers";
+
+export type APIRequestTransformer<Z extends z.ZodType<any, any>> = (
+  req: Request
+) => Promise<z.infer<Z>>;
+
+export type APIResponseTransformer<Z extends z.ZodType<any, any>> = (
+  res: Response
+) => Promise<z.infer<Z>>;
+
+/** Represents a transformation from one API format to another. */
+type APITransformation = `${APIFormat}->${APIFormat}`;
+
+type APIRequestTransformerMap = {
+  [key in APITransformation]?: APIRequestTransformer<any>;
+};
+
+type APIResponseTransformerMap = {
+  [key in APITransformation]?: APIResponseTransformer<any>;
+};
+
+export const API_REQUEST_TRANSFORMERS: APIRequestTransformerMap = {
+  "anthropic-text->anthropic-chat": transformAnthropicTextToAnthropicChat,
+  "openai->anthropic-chat": transformOpenAIToAnthropicChat,
+  "openai->anthropic-text": transformOpenAIToAnthropicText,
+  "openai->openai-text": transformOpenAIToOpenAIText,
+  "openai->openai-image": transformOpenAIToOpenAIImage,
+  "openai->google-ai": transformOpenAIToGoogleAI,
+};
+
+export const API_REQUEST_VALIDATORS: Record<APIFormat, z.ZodSchema<any>> = {
+  "anthropic-chat": AnthropicV1MessagesSchema,
+  "anthropic-text": AnthropicV1TextSchema,
+  openai: OpenAIV1ChatCompletionSchema,
+  "openai-text": OpenAIV1TextCompletionSchema,
+  "openai-image": OpenAIV1ImagesGenerationSchema,
+  "google-ai": GoogleAIV1GenerateContentSchema,
+  "mistral-ai": MistralAIV1ChatCompletionsSchema,
+};
+export { AnthropicChatMessage } from "./kits/anthropic-chat/schema";
+export { AnthropicV1MessagesSchema } from "./kits/anthropic-chat/schema";
+export { AnthropicV1TextSchema } from "./kits/anthropic-text/schema";
+
+export interface APIFormatKit<T extends APIFormat, P> {
+  name: T;
+  /** Zod schema for validating requests in this format. */
+  requestValidator: z.ZodSchema<any>;
+  /** Flattens non-sting prompts (such as message arrays) into a single string. */
+  promptStringifier: (prompt: P) => string;
+  /** Counts the number of tokens in a prompt. */
+  promptTokenCounter: (prompt: P, model: string) => Promise<number>;
+  /** Counts the number of tokens in a completion. */
+  completionTokenCounter: (
+    completion: string,
+    model: string
+  ) => Promise<number>;
+  /** Functions which transform requests from other formats into this format. */
+  requestTransformers: APIRequestTransformerMap;
+  /** Functions which transform responses from this format into other formats. */
+  responseTransformers: APIResponseTransformerMap;
+}
+export { GoogleAIChatMessage } from "./kits/google-ai";
+export { MistralAIChatMessage } from "./kits/mistral-ai";
+
+export { OpenAIChatMessage } from "./kits/openai/schema";
+export { flattenAnthropicMessages } from "./kits/anthropic-chat/stringifier";

src/shared/api-support/kits/README.md

@@ -0,0 +1,4 @@
+# API Kits
+This directory contains "kits" for each supported language model API. Each kit implements the `APIFormatKit` interface and provides functionality that the proxy application needs to be able to validate requests, transform prompts and responses, tokenize text, and so forth.
+
+## Structure