CodeRunner - Online Compiler

A modern online compiler supporting C++, Python, and Java with Docker containerization.

🚀 Quick Start

Prerequisites

• Node.js 18+
• Docker Desktop
• Git

Installation

1. Clone and install dependencies:

npm install

2. Build Docker images:

npm run docker:build

3. Start the application:

# Start both frontend and backend
npm run final

# Or start separately:
npm run dev          # Frontend (Next.js)
npm run dev:server   # Backend API

🐳 Docker Setup

The application uses separate Docker containers for each language:

• C++: GCC 12 with compilation and execution
• Python: Python 3.11 with standard library
• Java: OpenJDK 17 with compilation and execution

Building Docker Images

cd docker
chmod +x build-images.sh
./build-images.sh

🔧 Architecture

┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
│   Frontend      │    │   Backend API   │    │   Docker        │
│   (Next.js)     │───▶│   (Express.js)  │───▶│   Containers    │
│   Port 3000     │    │   Port 3001     │    │   Isolated      │
└─────────────────┘    └─────────────────┘    └─────────────────┘

API Endpoints

• POST /api/compile - Compile and execute code
• GET /api/health - Health check

Request Format

{
  "language": "cpp|python|java",
  "code": "source code string",
  "input": "optional input string"
}

Response Format

{
  "output": "execution output",
  "success": true,
  "exitCode": 0,
  "executionTime": 1.23,
  "language": "cpp"
}

🔒 Security Features

• Container Isolation: Each execution runs in a separate Docker container
• Resource Limits: Memory (128MB) and CPU (50%) restrictions
• Time Limits: 10s compilation, 5s execution timeout
• Network Isolation: Containers have no network access
• Read-only Mounts: Source code mounted as read-only
• Auto Cleanup: Containers and temp files automatically removed

🛠️ Development

Frontend Development

npm run dev

Backend Development

npm run dev:server

Full Stack Development

npm run final

📁 Project Structure

├── app/                 # Next.js frontend
│   ├── api/            # API routes
│   ├── components/     # React components
│   └── globals.css     # Global styles
├── server/             # Express.js backend
│   └── index.js        # Main server file
├── docker/             # Docker configurations
│   ├── cpp/           # C++ runtime
│   ├── python/        # Python runtime
│   ├── java/          # Java runtime
│   └── build-images.sh # Build script
└── components/         # Shared UI components

🚀 Deployment

For production deployment:

1. Build Docker images on your server
2. Configure environment variables
3. Set up reverse proxy (nginx)
4. Enable HTTPS
5. Configure rate limiting

🔧 Environment Variables

PORT=3001
DOCKER_HOST=unix:///var/run/docker.sock
MAX_EXECUTION_TIME=15000
MAX_MEMORY=128

📝 Supported Languages

Language	Version	Compiler/Runtime
C++	GCC 12	g++
Python	3.11	python
Java	17	javac + java

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test with Docker containers
5. Submit a pull request

📄 License

MIT License - see LICENSE file for details.