Meeting Booking System

A modern, full-stack meeting room booking application built with Next.js, Express.js, and Prisma ORM. Features advanced booking management with race condition protection, soft-delete functionality, and admin capabilities.

🚀 Features

Core Functionality

• User Authentication: Secure user registration and login with JWT tokens
• Room Management: Create, view, and manage meeting rooms
• Booking System: Reserve rooms with time slot management
• Booking Cancellation: Cancel future bookings with soft-delete functionality
• Admin Dashboard: Advanced administrative controls

Advanced Features

• Race Condition Protection: Transaction-based booking with FOR UPDATE locking
• Unique Constraints: Prevents double-booking of rooms using database constraints
• Soft Delete: Bookings are marked as deleted but preserved in database
• Admin Controls: Room deletion with cascade handling, user promotion
• Role-Based Access: User and Admin roles with different permissions

🛠️ Tech Stack

Backend

• Framework: Express.js with TypeScript
• Database: PostgreSQL
• ORM: Prisma 6.18.0
• Authentication: JWT (jsonwebtoken)
• Security: bcryptjs for password hashing

Frontend

• Framework: Next.js 15 with App Router
• Language: TypeScript
• Styling: Tailwind CSS
• HTTP Client: Axios
• State Management: React Hooks

📋 Prerequisites

• Node.js 18+ and npm
• PostgreSQL database
• Docker and Docker Compose (optional, for containerized setup)

⚙️ Installation

1. Clone the repository

git clone https://github.com/Facelles/last_task.git
cd meeting-booking

2. Backend Setup

cd backend

# Install dependencies
npm install

# Create .env file
cat > .env << EOF
DATABASE_URL="postgresql://user:password@localhost:5432/meeting_booking"
JWT_SECRET="your_jwt_secret_key"
PORT=5050
NODE_ENV=development
EOF

# Run database migrations
npx prisma migrate dev --name init

# Start the backend server
npm run dev

3. Frontend Setup

cd ../frontend

# Install dependencies
npm install

# Create .env.local file (optional, uses default API URL)
cat > .env.local << EOF
NEXT_PUBLIC_API_URL="http://localhost:5050/api"
EOF

# Start the development server
npm run dev

The frontend will be available at http://localhost:3000

🐳 Docker Setup

cd backend

# Build and start services
docker-compose up -d

# Run migrations
docker-compose exec backend npx prisma migrate dev

📁 Project Structure

meeting-booking/
├── backend/
│   ├── src/
│   │   ├── config/          # Database configuration
│   │   ├── middleware/      # Authentication middleware
│   │   ├── models/          # Prisma models
│   │   ├── routes/          # API routes
│   │   ├── services/        # Business logic
│   │   ├── types/           # TypeScript type definitions
│   │   └── index.ts         # Server entry point
│   ├── prisma/
│   │   └── schema.prisma    # Database schema
│   └── package.json
│
├── frontend/
│   ├── src/
│   │   ├── app/
│   │   │   ├── api/         # API route handlers
│   │   │   ├── auth/        # Authentication pages
│   │   │   ├── bookings/    # Booking management
│   │   │   ├── rooms/       # Room management
│   │   │   ├── dashboard/   # User dashboard
│   │   │   └── layout.tsx   # Root layout
│   │   ├── hook/            # Custom React hooks
│   │   └── services/        # API service layer
│   └── package.json
└── README.md

🔐 Authentication

User Roles

• User: Can create bookings, cancel own bookings, view own bookings
• Admin: Full access including room management and user promotion

First User Benefits

The first user to register automatically becomes an admin.

Login Credentials (Example)

Username: admin
Email: admin@test.com
Password: password123

🔄 API Endpoints

Authentication

• POST /api/auth/register - Register new user
• POST /api/auth/login - Login user
• POST /api/auth/logout - Logout user
• GET /api/auth/me - Get current user profile
• POST /api/auth/promote - Promote user to admin

Rooms

• GET /api/rooms - Get all rooms
• GET /api/rooms/:id - Get room details
• POST /api/rooms - Create new room (authenticated)
• DELETE /api/rooms/:id - Delete room (admin only)

Bookings

• GET /api/bookings - Get user's bookings
• POST /api/bookings - Create new booking
• GET /api/bookings/:id - Get booking details
• DELETE /api/bookings/:id - Cancel booking (soft-delete)
• POST /api/bookings/check-availability - Check room availability

🔒 Race Condition Protection

The booking system uses transaction-based locking to prevent race conditions:

// Bookings are created within a transaction with FOR UPDATE lock
// This ensures only one booking can be created for the same time slot
SELECT ... FROM bookings ... WHERE room_id = ? FOR UPDATE;

💾 Database Schema Highlights

Soft Delete Pattern

model Booking {
  // ...
  deletedAt DateTime?  // Null = active, Set = soft-deleted
}

Unique Constraint

@@unique([userId, roomId, startTime, endTime])
// Prevents duplicate bookings for same user, room, and time

🧪 Testing

Run Backend Tests

cd backend
npm run test

Manual API Testing

# Login
curl -X POST http://localhost:5050/api/auth/login \
  -H "Content-Type: application/json" \
  -d '{"username":"admin","email":"admin@test.com","password":"password123"}'

# Create booking
curl -X POST http://localhost:5050/api/bookings \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"room_id":1,"start_time":"2025-11-20T10:00:00Z","end_time":"2025-11-20T11:00:00Z"}'

🚀 Deployment

Backend Deployment

cd backend

# Build
npm run build

# Set environment variables on production server
export DATABASE_URL="your_production_db_url"
export JWT_SECRET="your_production_secret"
export NODE_ENV="production"

# Start
npm run start

Frontend Deployment

cd frontend

# Build
npm run build

# Start
npm run start

📝 Environment Variables

Backend (.env)

DATABASE_URL=postgresql://user:password@localhost:5432/db_name
JWT_SECRET=your_secret_key
PORT=5050
NODE_ENV=development

Frontend (.env.local)

NEXT_PUBLIC_API_URL=http://localhost:5050/api

🐛 Troubleshooting

"Cannot find module 'prisma'"

npm install
npx prisma generate

Database connection errors

• Ensure PostgreSQL is running
• Check DATABASE_URL environment variable
• Verify database exists and credentials are correct

Port already in use

# Change PORT in backend .env file
# Or kill process using port:
lsof -ti:5050 | xargs kill -9

📚 Documentation

• Prisma Documentation
• Next.js Documentation
• Express.js Guide
• PostgreSQL Docs

📄 License

This project is open source and available under the MIT License.

👤 Author

Created by Facelles

🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.