🛠️ CodeRush Backend — Scalable API & Code Execution Engine

This is the backend service for CodeRush, a multi-language coding platform where users can solve randomized, topic-specific problems and track their coding progress. The backend is responsible for user authentication, question management, Docker-based code execution, and MongoDB data storage.

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🚀 Features

• 🧑‍💻 User Authentication (JWT)

  • Sign up, log in, and manage secure sessions using JSON Web Tokens.

• 📚 Topic-Based Question Generation

  • Serve random coding questions based on selected topics and programming languages.

• 🐳 Secure Code Execution

  • Run submitted code inside Docker containers for C++, Python, JavaScript, and Java.
  • Each container is isolated for safety and consistency.

• 📊 Progress & Submission Tracking

  • Store solved problems, user history, and growth insights for later retrieval.

• 🧩 REST API for Frontend Integration

  • Clean and modular API routes that power the frontend application.

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🧱 Tech Stack

Layer	Tech Used
Server	Node.js, Express.js
Auth	JWT (JSON Web Tokens)
DB	MongoDB + Mongoose
Execution	Docker (per-language images)
Utilities	Dockerode, fs, child_process

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📦 Project Structure

/coderush-backend
├── controllers/
├── routes/
├── services/           # Code execution logic
├── models/             # User & Question schemas
├── utils/              # Docker helpers, validators
├── .env
├── server.js
└── package.json

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⚙️ Setup & Installation

🔧 Prerequisites

• Node.js v18+
• Docker (installed and running)
• MongoDB (local or Atlas)

📥 Steps

# Clone the repo
git clone https://github.com/HYDRO2070/Code-Complier.git
cd Code-Complier

# Install dependencies
npm install

# Set up environment variables
cp .env.example .env

# Start the server
npm run dev

Ensure Docker is running locally and that .env is properly configured.

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🔐 Environment Variables

Create a .env file with the following:

PORT=5000
MONGO_URI=your_mongodb_uri
JWT_SECRET=your_jwt_secret
DOCKER_SOCKET=/var/run/docker.sock

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🔌 Available API Endpoints

Base URL: http://localhost:5000/api

Method	Endpoint	Description
POST	/auth/signup	Create a new user
POST	/auth/login	Authenticate user and return token
GET	/user/profile	Get logged-in user's profile
POST	/questions/random	Fetch a random question by topic
POST	/code/execute	Run submitted code via Docker
GET	/user/history	Get solved problems by user

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🧪 Code Execution via Docker

• Each submission is sent to a language-specific Docker container.
• Output, errors, or runtime exceptions are captured and returned to the client.
• Prevents direct code execution on the host machine for maximum security.

Supported languages:

• ✅ C++
• ✅ Python
• ✅ JavaScript
• ✅ Java

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🧼 Linting & Formatting

# Lint with ESLint
npm run lint

# Format with Prettier
npm run format

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📈 Future Enhancements

• ✅ Execution timeout safeguards
• 🔜 Container reuse with lifecycle management
• 🔜 Rate limiting & abuse protection
• 🔜 Caching frequently used questions
• 🔜 Unit & integration testing with Jest

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🤝 Contributing

We welcome contributions! Please open an issue or submit a pull request for improvements, bug fixes, or features.