Open CodeRabbit Server

A powerful TypeScript backend server that provides AI-powered code review services for VSCode extensions. CodeRabbit analyzes code changes, generates intelligent comments, and provides comprehensive review summaries using advanced AI models.

DISCLAIMER: This project is NOT affiliated with, endorsed by, or connected to CodeRabbit AI or any of its services.

🚀 Features

• AI-Powered Code Reviews: Intelligent analysis using Google Gemini, OpenAI GPT models
• Real-time Communication: WebSocket-based real-time updates via tRPC
• Multi-Provider AI Support: Flexible AI provider configuration (Google, OpenAI )
• Comprehensive Analysis:
  • Code review comments with categorization (issues, suggestions, nitpicks)
  • PR title generation
  • Review summaries and objectives
  • Code walkthrough generation
• Robust Infrastructure:
  • Rate limiting and request validation
  • File size and count limits
  • Comprehensive logging and monitoring
  • Retry mechanisms with exponential backoff
  • SSL support for secure connections
• Production Ready: Docker support, health checks, and metrics endpoints

📋 Prerequisites

• Node.js 20+
• npm or yarn
• AI Provider API Key (Google Generative AI, OpenAI)

🛠️ Installation

1. Clone the repository

   git clone https://github.com/creding/open-coderabbit-server
   cd open-coderabbit-server

2. Install dependencies

   npm install

3. Configure environment variables

   cp .env.example .env

   Edit .env with your configuration:

   # Server Configuration
   PORT=5353
   HOST=localhost
   SSL=false
   
   # AI Provider Configuration
   AI_PROVIDER=google  # google, openai
   GOOGLE_GENERATIVE_AI_API_KEY=your_google_api_key
   OPENAI_API_KEY=your_openai_api_key
   
   # AI Models
   GOOGLE_AI_MODEL=models/gemini-2.5-flash
   OPENAI_AI_MODEL=gpt-4o-mini
   
   # File Validation
   MAX_FILE_SIZE=10485760          # 10MB per file
   MAX_FILES_PER_REVIEW=50         # Max files per review
   MAX_TOTAL_SIZE=52428800         # 50MB total
   
   # Rate Limiting
   RATE_LIMIT_REQUESTS=10          # Requests per window
   RATE_LIMIT_WINDOW_MS=60000      # 1 minute window
   
   # Performance
   REVIEW_TIMEOUT_MS=300000        # 5 minute timeout
   
   # Logging
   LOG_LEVEL=info                  # error, warn, info, debug
   LOG_TO_FILE=false

🚀 Usage

Development Mode

npm run dev

Production Build

npm run build
npm start

🔌 Connecting VSCode Extension

To use your self-hosted Open CodeRabbit server with the CodeRabbit VSCode extension, follow these steps:

Prerequisites

1. CodeRabbit VSCode Extension: Install the CodeRabbit extension (version 0.12.1 or higher)
2. Running Server: Ensure your Open CodeRabbit server is running and accessible
3. Network Access: Make sure the server URL is reachable and WebSocket connections are allowed

Connection Steps

1. Open VSCode and navigate to the CodeRabbit extension

2. Logout if previously logged in to CodeRabbit cloud service

3. Click "Self hosting CodeRabbit?" button (located below the "Use CodeRabbit for free" button)

4. Enter your server URL when prompted:

   http://localhost:5353
   

   Or if running on a different host:

   http://your-server-ip:5353
   

5. Select your Git provider:

   • GitHub
   • GitHub Enterprise
   • GitLab
   • Self-Hosted GitLab

6. Provide authentication (if using GitHub/GitHub Enterprise):

   • Enter your GitHub Personal Access Token
   • Required permissions: repo, read:user

Verification

Once connected, you should see:

• ✅ Connection status indicator in the extension
• Access to code review features in VSCode
• Real-time AI-powered code analysis

Troubleshooting Connection Issues

Extension can't connect to server:

# Check if server is running
docker ps
# or
curl http://localhost:5353/health

WebSocket connection failed:

• Ensure firewall allows connections on port 5353
• Check that server is binding to 0.0.0.0 (not just localhost)
• Verify no proxy is blocking WebSocket connections

Server URL not reachable:

• Test server accessibility: curl http://your-server:5353/health
• Check network connectivity between VSCode and server
• Ensure Docker port mapping is correct: 0.0.0.0:5353->5353/tcp

Using Docker

The Open CodeRabbit server is fully containerized and production-ready with Docker support.

Quick Start

Using the Docker Management Script (Recommended)

# Start development environment with hot reload
./scripts/docker.sh dev

# Start production environment
./scripts/docker.sh start

# Stop all containers
./scripts/docker.sh stop

# View logs
./scripts/docker.sh logs

# Check health
./scripts/docker.sh health

Manual Docker Commands

Build the image:

docker build -t open-coderabbit-server .

Run production container:

docker run -d --name open-coderabbit -p 5353:5353 --env-file .env open-coderabbit-server

Using Docker Compose:

# Production
docker-compose up -d

# Development with hot reload
docker-compose -f docker-compose.dev.yml up -d

Docker Configuration

Multi-Stage Dockerfile

• Builder stage: Compiles TypeScript and installs all dependencies
• Production stage: Minimal runtime image with only production dependencies
• Base image: node:20-alpine for security and size optimization

Environment Variables

The container uses the same environment variables as the local setup. Ensure your .env file is properly configured:

# Copy example environment file
cp .env.example .env
# Edit with your API keys and configuration

Health Checks

Both Docker Compose configurations include health checks:

• Endpoint: GET /health
• Interval: 30 seconds
• Timeout: 10 seconds
• Retries: 3
• Start period: 40 seconds

Logging

Production containers are configured with log rotation:

• Max file size: 10MB
• Max files: 3
• Format: JSON

Development vs Production

Feature	Development	Production
File	docker-compose.dev.yml	docker-compose.yml
Hot Reload	✅ Volume mounted	❌ Built-in
Build Target	builder stage	Final stage
Dependencies	All (dev + prod)	Production only
Restart Policy	unless-stopped	unless-stopped
Health Checks	✅ Enabled	✅ Enabled

Docker Management Script

The scripts/docker.sh script provides convenient commands:

./scripts/docker.sh [COMMAND]

Commands:
  build       Build the Docker image
  dev         Start development environment with hot reload
  start       Start production container
  stop        Stop running containers
  restart     Restart containers
  logs        Show container logs
  shell       Open shell in running container
  clean       Remove containers and images
  health      Check container health
  help        Show this help message

Troubleshooting

Container won't start:

# Check logs
./scripts/docker.sh logs

# Or manually
docker-compose logs -f

Health check failing:

# Test health endpoint
curl http://localhost:5353/health

# Check container status
docker ps

Port already in use:

# Find process using port 5353
lsof -i :5353

# Or change port in docker-compose.yml
ports:
  - "5354:5353"  # Use different external port

📡 API Endpoints

Health Check

GET /health

Returns server health status:

• Healthy status: Returns plain text "OK" with HTTP 200 (VSCode extension compatible)
• Degraded/Unhealthy status: Returns detailed JSON with metrics and diagnostics

Example responses:

# Healthy server
curl http://localhost:5353/health
# Response: "OK" (Content-Type: text/plain)

Metrics

GET /metrics

Returns performance metrics and monitoring data.

tRPC WebSocket

WS /trpc

Real-time communication for code review requests and updates.

🏗️ Architecture

Core Components

• server.ts - Main HTTP/WebSocket server with SSL support
• router.ts - tRPC router handling review requests and subscriptions
• constants.ts - Environment configuration and validation

Services

• services/reviewService.ts - Core review orchestration logic
• services/ai/ - AI integration layer
  • index.ts - Unified AI provider interface
  • prompts.ts - AI prompt templates
  • schemas.ts - Zod validation schemas
  • types.ts - TypeScript type definitions

Utilities

• utils/config.ts - Configuration management
• utils/fileValidator.ts - File validation and limits
• utils/logger.ts - Structured logging
• utils/monitor.ts - Performance monitoring and metrics
• utils/rateLimiter.ts - Request rate limiting
• utils/retry.ts - Retry logic with exponential backoff

Types

• types.ts - Shared TypeScript definitions and Zod schemas

🧪 Testing

The project includes comprehensive test coverage with Vitest:

# Run all tests
npm test

# Run tests in watch mode
npm run test:watch

# Run tests with coverage
npm run test:coverage

Test Structure

• tests/services/ - Service layer tests
• tests/utils/ - Utility function tests
• tests/fixtures/ - Shared test data
• tests/helpers/ - Test utilities and helpers

🔧 Development

Code Quality

# Lint code
npm run lint

# Format code
npm run format

# Type checking
npx tsc --noEmit

Project Structure

src/
├── constants.ts          # Environment configuration
├── router.ts            # tRPC routes
├── server.ts            # Main server
├── types.ts             # Shared types
├── services/
│   ├── ai/              # AI provider integration
│   └── reviewService.ts # Core review logic
└── utils/               # Utility functions

tests/
├── fixtures/            # Test data
├── helpers/             # Test utilities
├── services/            # Service tests
└── utils/               # Utility tests

🚀 Deployment

Environment Variables

Variable	Description	Default
PORT	Server port	5353
HOST	Server host	localhost
SSL	Enable SSL	false
AI_PROVIDER	AI provider (google/openai)	google
GOOGLE_GENERATIVE_AI_API_KEY	Google AI API key	Required
OPENAI_API_KEY	OpenAI API key	Optional
MAX_FILE_SIZE	Max file size in bytes	10485760 (10MB)
MAX_FILES_PER_REVIEW	Max files per review	50
RATE_LIMIT_REQUESTS	Rate limit requests	10
RATE_LIMIT_WINDOW_MS	Rate limit window	60000 (1 min)
REVIEW_TIMEOUT_MS	Review timeout	300000 (5 min)
LOG_LEVEL	Logging level	info

Docker Deployment

The included Dockerfile uses multi-stage builds for optimized production images:

1. Builder stage: Installs dependencies and builds TypeScript
2. Production stage: Creates minimal runtime image

Health Monitoring

The server provides built-in health checks and metrics:

• Health endpoint (/health): Returns plain text "OK" for healthy status, detailed JSON for issues
• Metrics endpoint (/metrics): Provides comprehensive performance and system data
• Structured logging with configurable levels (error, warn, info, debug)
• Request monitoring and error tracking with retry mechanisms

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests for new functionality
5. Ensure all tests pass
6. Submit a pull request

📝 License

ISC License

🔗 Related Projects

This server is designed to work with the CodeRabbit VSCode extension for seamless code review integration.

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🚀 Ready to revolutionize your code reviews with AI!