License Management System

A comprehensive full-stack application for managing licenses, subscriptions, and customers. Built with React (TypeScript + Vite) frontend and Node.js/Express backend with PostgreSQL database.

🚀 Features

Admin Features

• Dashboard: System overview with metrics and recent activities
• Customer Management: CRUD operations for customer accounts
• Subscription Pack Management: Create and manage subscription plans
• Subscription Management: Approve/reject requests, assign/unassign subscriptions
• JWT Authentication: Secure admin authentication

Customer Features

• Registration & Login: Account creation and authentication
• Dashboard: Personal subscription overview
• Subscription Management: Request new subscriptions, view current plan
• Profile Management: View and manage account information
• Subscription History: Track past subscriptions

SDK APIs

• API Key Authentication: Separate authentication for mobile/desktop SDKs
• Subscription Operations: Get current subscription, request new, deactivate
• History Access: Retrieve subscription history with pagination

🏗️ Architecture

Tech Stack

• Frontend: React 18, TypeScript, Vite, TailwindCSS, React Query, React Router
• Backend: Node.js, Express.js, TypeScript, Sequelize ORM
• Database: PostgreSQL
• Authentication: JWT for frontend, API Keys for SDK
• Development: Docker, Docker Compose

Project Structure

├── backend/                 # Express.js API server
│   ├── src/
│   │   ├── config/         # Database and logger configuration
│   │   ├── models/         # Sequelize models
│   │   ├── routes/         # API route handlers
│   │   ├── middleware/     # Authentication and validation middleware
│   │   ├── scripts/        # Database seeding scripts
│   │   └── server.ts       # Main server file
│   ├── Dockerfile
│   ├── docker-compose.yml
│   └── package.json
├── frontend/               # React application
│   ├── src/
│   │   ├── components/     # Reusable components
│   │   ├── pages/          # Page components
│   │   ├── contexts/       # React contexts
│   │   ├── api/           # API client functions
│   │   ├── lib/           # Utilities and helpers
│   │   └── types/         # TypeScript type definitions
│   ├── package.json
│   └── vite.config.ts
└── PROJECT_README.md       # This file

🛠️ Setup Instructions

Prerequisites

• Node.js 18+ and npm
• PostgreSQL 15+
• Docker and Docker Compose (optional)

Option 1: Docker Setup (Recommended)

1. Clone the repository

   git clone <repository-url>
   cd license-management-system

2. Start with Docker Compose

   cd backend
   docker-compose up -d

3. Seed the database

   docker-compose exec api npm run seed

4. Setup frontend

   cd ../frontend
   npm install
   cp env.example .env
   npm run dev

The application will be available at:

• Frontend: http://localhost:3000
• Backend API: http://localhost:8080
• Health Check: http://localhost:8080/health

Option 2: Manual Setup

Backend Setup

1. Install dependencies

   cd backend
   npm install

2. Setup PostgreSQL database

   # Create database
   createdb license_management

3. Configure environment

   cp env.example .env
   # Edit .env with your database credentials

4. Build and start server

   npm run build
   npm start
   
   # For development with auto-reload
   npm run dev

5. Seed database with sample data

   npm run seed

Frontend Setup

1. Install dependencies

   cd frontend
   npm install

2. Configure environment

   cp env.example .env
   # Edit .env with your API URL

3. Start development server

   npm run dev

🔐 Sample Login Credentials

After running the seed script, you can use these credentials:

Admin

• Email: admin@example.com
• Password: admin123

Customers

• Email: john@example.com / Password: customer123
• Email: jane@example.com / Password: customer123
• Email: bob@example.com / Password: customer123

📋 Completed Customer Flow

Customer Login → View Profile → Request Subscription

1. Customer Registration/Login

   • Navigate to http://localhost:3000/signup (new users) or http://localhost:3000/login
   • Use customer credentials from above
   • JWT token stored securely for session management

2. Dashboard Overview

   • View current subscription status
   • See account statistics
   • Quick access to subscription management

3. Profile Management

   • View personal information
   • Account activity statistics
   • Edit profile (placeholder)

4. Subscription Request Flow

   • Browse available subscription plans
   • Select desired plan
   • Submit subscription request
   • Request sent to admin for approval

5. Subscription Management

   • View current active subscription
   • Deactivate subscription if needed
   • Access subscription history

🔧 API Documentation

The API follows the OpenAPI 3.0 specification provided in openapi.yaml. Key endpoints include:

Frontend APIs (JWT Authentication)

• POST /api/admin/login - Admin authentication
• POST /api/customer/login - Customer authentication
• POST /api/customer/signup - Customer registration
• GET /api/v1/admin/dashboard - Admin dashboard data
• GET /api/v1/customer/subscription - Customer's current subscription

SDK APIs (API Key Authentication)

• POST /sdk/auth/login - SDK authentication (returns API key)
• GET /sdk/v1/subscription - Current subscription via SDK
• POST /sdk/v1/subscription - Request subscription via SDK
• DELETE /sdk/v1/subscription - Deactivate subscription via SDK

🧪 Testing

Backend Tests

cd backend
npm test

Frontend Tests

cd frontend
npm test

🚀 Production Deployment

Backend

1. Build the application: npm run build
2. Set production environment variables
3. Deploy using Docker or process manager (PM2)
4. Configure reverse proxy (nginx)
5. Setup SSL certificates

Frontend

1. Build for production: npm run build
2. Deploy static files to CDN or web server
3. Configure environment variables for production API

🌟 Key Features Implemented

Authentication & Security

• ✅ JWT authentication for frontend APIs
• ✅ API key authentication for SDK APIs
• ✅ Role-based access control (Admin/Customer)
• ✅ Route guards and protected routes
• ✅ Password hashing with bcrypt
• ✅ Input validation and sanitization

Business Logic

• ✅ Single active subscription per customer rule
• ✅ Subscription lifecycle management (requested → approved → active → inactive/expired)
• ✅ Soft delete for customers and subscription packs
• ✅ Automatic subscription expiry calculation

User Experience

• ✅ Responsive design with TailwindCSS
• ✅ Toast notifications for user feedback
• ✅ Loading states and error handling
• ✅ Intuitive navigation and routing
• ✅ Form validation with helpful error messages

API Integration

• ✅ Axios interceptors for token management
• ✅ React Query for efficient data fetching and caching
• ✅ Consistent error handling across the application
• ✅ Pagination support for list endpoints

📚 Additional Features for Production

While this implementation provides a solid foundation, consider these enhancements for production:

1. Enhanced Security

   • Rate limiting per user
   • CSRF protection
   • Input sanitization
   • API versioning

2. Advanced Features

   • Email notifications
   • Payment integration
   • Advanced analytics
   • Audit logging

3. Monitoring & DevOps

   • Application monitoring
   • Log aggregation
   • Performance metrics
   • CI/CD pipeline

4. Scalability

   • Database optimization
   • Caching layer (Redis)
   • Load balancing
   • Microservices architecture

🐛 Troubleshooting

Common Issues

1. Database Connection Error

   • Ensure PostgreSQL is running
   • Check database credentials in .env file
   • Verify database exists

2. Frontend API Calls Failing

   • Check backend server is running on port 8080
   • Verify CORS configuration
   • Check network proxy settings

3. Authentication Issues

   • Clear browser localStorage
   • Check JWT_SECRET in backend .env
   • Verify token expiration settings

Logs

• Backend logs: backend/logs/
• Browser console for frontend errors
• Docker logs: docker-compose logs api

📞 Support

For questions or issues, please refer to:

• API documentation in openapi.yaml
• System design in README.md
• Code comments and TypeScript types

---

License Management System - A modern, scalable solution for subscription and license management.