Mini LeetCode

A coding practice platform with containerized code execution, test cases, and leaderboard functionality.

Table of Contents

• About
• Features
• Tech Stack
• Screenshots
• Installation
• API Endpoints
• Containerized Code Execution
• Database Models
• Future Enhancements
• Contributing
• License

About

Mini LeetCode is a web-based coding practice platform designed to help developers improve their programming skills by solving coding challenges. The platform provides a secure environment for code execution using containerization technology, supports multiple programming languages, and includes features like user authentication, problem solving, and leaderboards.

Features

• User Authentication: Secure registration and login system with JWT tokens
• Coding Problems: Problems categorized by difficulty levels (Easy, Medium, Hard)
• Multi-language Support: Write solutions in JavaScript, Python, Java, or C++
• Secure Code Execution: Containerized execution environment for safety
• Test Case Validation: Automated testing of user submissions against predefined test cases
• Leaderboard System: Track and compare your progress with other users
• Submission History: View and review your previous submissions
• Modern UI: Clean and responsive interface built with React and Material-UI

Tech Stack

Backend

• Node.js with Express.js - Fast, unopinionated web framework
• MongoDB with Mongoose - Flexible NoSQL database
• Docker - Containerization for secure code execution
• JWT - Secure authentication mechanism

Frontend

• React.js - Component-based UI library
• Material-UI - Modern React UI framework
• Monaco Editor - Code editor with syntax highlighting
• React Router - Declarative routing for React

Screenshots

(Add screenshots of your application here)

Installation

Prerequisites

• Node.js (v14 or higher)
• MongoDB (local or cloud instance)
• Docker Desktop
• npm or yarn

Steps

1. Clone the repository:

   git clone https://github.com/itsaahsan/Mini-LeetCode.git
   cd Mini-LeetCode

2. Install backend dependencies:

   npm install

3. Install frontend dependencies:

   cd client && npm install

4. Set up environment variables:

   • Create a .env file in the root directory
   • Add your MONGO_URI and JWT_SECRET

5. Start Docker Desktop and ensure it's running

6. Run the development server:

   cd .. && npm run dev

7. Open your browser and navigate to http://localhost:3000

API Endpoints

Authentication

• POST /api/auth/register - Register a new user
• POST /api/auth/login - Login user
• GET /api/auth/profile - Get user profile (protected)

Problems

• GET /api/problems - Get all problems
• GET /api/problems/:id - Get problem by ID
• POST /api/problems - Create a new problem (protected)

Submissions

• POST /api/submissions - Submit code for a problem (protected)
• GET /api/submissions - Get user submissions (protected)
• GET /api/submissions/:id - Get submission by ID (protected)

Leaderboard

• GET /api/leaderboard - Get leaderboard

Code Execution

• POST /api/code/execute - Execute code with test cases (protected)

Containerized Code Execution

The application uses Docker to execute user code in isolated containers for security. This approach provides:

• Isolation: Each code execution runs in its own container
• Resource Limits: Memory and CPU usage are controlled
• Security: Network access is disabled to prevent malicious code
• Multi-language Support: Supports JavaScript (Node.js), Python, Java, and C++

Each code execution is limited by:

• Memory: 100MB
• Network: Disabled
• Time: Docker default timeout

Database Models

User

• username
• email
• password (hashed)
• score
• problemsSolved
• createdAt

Problem

• title
• description
• difficulty (Easy, Medium, Hard)
• points
• testCases (array)
• constraints
• examples
• tags
• createdAt

Submission

• userId (reference to User)
• problemId (reference to Problem)
• code
• language
• status (Pending, Accepted, Wrong Answer, etc.)
• executionTime
• memoryUsage
• testCasesPassed
• totalTestCases
• submittedAt

Future Enhancements

• Real-time code execution with timeouts
• More sophisticated test case validation
• Syntax highlighting in code editor
• Discussion forums for problems
• Company-specific interview questions
• Progress tracking and statistics
• Dark mode support
• Mobile-responsive design

Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository
2. Create a new branch (git checkout -b feature/YourFeature)
3. Commit your changes (git commit -m 'Add some feature')
4. Push to the branch (git push origin feature/YourFeature)
5. Open a pull request

License

This project is licensed under the MIT License - see the LICENSE file for details.

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Built with ❤️ by [Ahsan]