Live Coding Arena

A real-time collaborative coding platform built with Spring Boot and MySQL.

Features

• User Authentication: Secure login/register for students, mentors, and administrators
• Real-time Collaboration: Multiple users can edit code simultaneously using WebSocket
• Problem Bank: Coding problems categorized by difficulty and topic
• Code Evaluation: Automatic code compilation and testing
• Leaderboard: Performance tracking and rankings
• Responsive Design: Works on desktop and mobile devices

Technology Stack

• Backend: Java 17, Spring Boot 3.2, Spring Security, Spring Data JPA
• Database: MySQL 8.0
• Frontend: HTML5, CSS3, JavaScript, Thymeleaf
• Real-time: WebSocket with STOMP protocol
• Code Editor: CodeMirror integration

Prerequisites

• Java 17 or higher
• Maven 3.6+
• MySQL 8.0+
• Git

Setup Instructions

1. Clone the Repository

git clone <repository-url>
cd java_project3

2. Database Setup

1. Install MySQL and start the service
2. Create a database (optional - application will create it automatically):

CREATE DATABASE livecoding_arena;

3. Update database credentials in src/main/resources/application.yml:

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/livecoding_arena?createDatabaseIfNotExist=true
    username: root
    password: your_password

3. Build and Run

# Build the project
mvn clean install

# Run the application
mvn spring-boot:run

4. Access the Application

• Open your browser and go to: http://localhost:8080
• Register a new account or use the sample data

Default Users

The application initializes with sample problems. You can register new users with different roles:

• Student: Can solve problems and view leaderboard
• Mentor: Can solve problems and access mentor features
• Admin: Full access to all features

API Endpoints

Authentication

• POST /api/auth/register - User registration
• POST /api/auth/login - User login

Problems

• GET /api/problems - Get all problems
• GET /api/problems/{id} - Get specific problem
• GET /api/problems/category/{category} - Filter by category
• GET /api/problems/difficulty/{difficulty} - Filter by difficulty

Submissions

• POST /api/submissions/submit - Submit code for evaluation

Leaderboard

• GET /api/leaderboard - Get user rankings

WebSocket Endpoints

• /ws - WebSocket connection endpoint
• /app/code.update - Send code updates
• /topic/code - Subscribe to code changes
• /app/cursor.update - Send cursor position
• /topic/cursor - Subscribe to cursor updates

Project Structure

src/
├── main/
│   ├── java/com/livecoding/arena/
│   │   ├── config/          # Configuration classes
│   │   ├── controller/      # REST controllers
│   │   ├── dto/            # Data Transfer Objects
│   │   ├── entity/         # JPA entities
│   │   ├── repository/     # Data repositories
│   │   ├── service/        # Business logic
│   │   ├── websocket/      # WebSocket handlers
│   │   └── LiveCodingArenaApplication.java
│   └── resources/
│       ├── static/         # CSS, JS, images
│       ├── templates/      # Thymeleaf templates
│       └── application.yml # Configuration
└── test/                   # Test classes

Usage

1. Register/Login: Create an account or login with existing credentials
2. Browse Problems: View available coding problems with filters
3. Code Editor: Select a problem and start coding
4. Real-time Collaboration: Share session with others for collaborative coding
5. Submit Solutions: Test and submit your code for evaluation
6. View Leaderboard: Check your ranking and progress

Development

Adding New Problems

Problems are initialized in ProblemService.initializeSampleProblems(). To add more:

createProblem(
    "Problem Title",
    "Problem description...",
    Problem.Difficulty.MEDIUM,
    "Category",
    "Test input",
    "Expected output"
);

Extending Code Evaluation

The CodeEvaluationService currently uses simplified evaluation. For production:

• Implement Docker containers for secure code execution
• Add support for multiple programming languages
• Integrate with online judges or testing frameworks

Security Notes

• Passwords are encrypted using BCrypt
• JWT tokens can be implemented for stateless authentication
• Input validation is applied to prevent SQL injection
• For production, implement proper code sandboxing

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

License

This project is licensed under the MIT License.

Java_LiveCodingArena