Transaction Microservice

A robust, scalable transaction management microservice built with NestJS, TypeScript, Prisma, PostgreSQL, Docker and Swagger. This service provides comprehensive transaction lifecycle management with real-time status tracking, validation, and API documentation.

🚀 Technologies Used

Core Framework

• NestJS - Progressive Node.js framework for building efficient and scalable server-side applications
• TypeScript - Strongly typed JavaScript for enhanced developer experience and code reliability

Database & ORM

• PostgreSQL - Robust, open-source relational database system
• Prisma - Next-generation ORM with type-safe database access and migrations
• pgAdmin - Web-based PostgreSQL administration and development platform

API & Documentation

• Swagger/OpenAPI - Interactive API documentation and testing interface
• class-validator - Decorator-based validation for DTOs

Development & Testing

• Jest - Comprehensive testing framework with coverage reporting
• ESLint - Code linting and formatting
• Prettier - Code formatting and style consistency
• Docker - Containerization for consistent development and deployment

📋 Features

• Transaction Management: Create, read, and manage transaction records
• Status Tracking: Real-time transaction status monitoring (PENDING, COMPLETED, FAILED)
• Data Validation: Comprehensive input validation using decorators
• API Documentation: Interactive Swagger UI for API exploration
• Database Migrations: Version-controlled database schema management
• Type Safety: Full TypeScript support with Prisma-generated types
• Testing Suite: Unit and E2E testing with Jest
• Docker Support: Containerized development and deployment

🏗️ Architecture

src/
├── main.ts                 # Application bootstrap and Swagger setup
├── prisma/
│   ├── prisma.module.ts   # Prisma module configuration
│   └── prisma.service.ts  # Database service wrapper
└── transaction/
    ├── dto/
    │   └── create-transaction.dto.ts  # Data transfer objects
    ├── entities/
    │   └── transaction.entity.ts      # Domain entities
    ├── transaction.controller.ts      # REST API endpoints
    ├── transaction.service.ts         # Business logic
    └── transaction.module.ts          # Module configuration

🚀 Quick Start

Prerequisites

• Node.js (v18 or higher)
• Docker and Docker Compose
• npm or yarn package manager

Installation

1. Clone the repository

   git clone `https://github.com/asabahebwa/transaction-microservice.git`
   cd transactionservice

2. Install dependencies

   npm install

3. Environment Setup Create a .env file in the root directory:

   # Database Configuration
   DATABASE_URL="postgresql://username:password@localhost:5432/transactiondb"
   POSTGRES_USER=username
   POSTGRES_PASSWORD=password
   POSTGRES_DB=transactiondb
   POSTGRES_PORT=5432
   
   # pgAdmin Configuration
   PGADMIN_DEFAULT_EMAIL=admin@example.com
   PGADMIN_DEFAULT_PASSWORD=admin
   PGADMIN_PORT=5050

4. Start the database

   docker-compose up -d

5. Run database migrations

   npx prisma migrate dev

6. Generate Prisma client

   npx prisma generate

Development

# Start development server with hot reload
npm run start:dev

# Start in debug mode
npm run start:debug

# Build for production
npm run build

# Start production server
npm run start:prod

📚 API Documentation

Once the application is running, access the interactive API documentation at:

• Swagger UI: http://localhost:3000/api
• pgAdmin: http://localhost:5050 (Database administration)

Available Endpoints

• POST /transaction - Create a new transaction
• GET /transaction - Retrieve all transactions
• GET /transaction/:id - Retrieve a specific transaction

🗄️ Database Schema

The service uses the following database schema:

model Transaction {
  id          Int      @id @default(autoincrement())
  status      Status
  accountId   String   @default(uuid())
  description String?
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt
}

enum Status {
  PENDING
  COMPLETED
  FAILED
}

🐳 Docker Deployment

The service includes Docker Compose configuration for easy deployment:

# Start all services
docker-compose up -d

# View logs
docker-compose logs -f

# Stop services
docker-compose down

🤝 Contributing

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

📄 License

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

🆘 Support

For support and questions:

• Create an issue in the repository
• Check the NestJS Documentation
• Visit the Prisma Documentation

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Built with ❤️ using NestJS, Prisma, and PostgreSQL