Transfer App Backend

This project is a secure, production-ready backend for a digital wallet and money transfer platform, built with NestJS and TypeScript.

Features

• User registration, login, and JWT authentication
• Password and PIN reset via email
• Wallet management (balance, funding)
• Money transfers between users
• Payment API integration (e.g., Paystack)
• Modular, scalable architecture
• Input validation and security best practices
• API documentation with Swagger
• Unit and e2e testing

Getting Started

Prerequisites

• Node.js (v16+ recommended)
• Yarn
• PostgreSQL

Installation

yarn install

Environment Setup

Create a .env file in the project root with the following variables:

PORT=3000
DATABASE_URL=postgres://user:password@localhost:5432/transfer_app
JWT_SECRET=your_jwt_secret
PAYSTACK_SECRET_KEY=your_paystack_secret_key

Running the App

# development
yarn start

# watch mode
yarn start:dev

# production
yarn start:prod

Testing

# unit tests
yarn test

# e2e tests
yarn test:e2e

# test coverage
yarn test:cov

API Endpoints

Auth

• POST /auth/register — Register a new user
• POST /auth/login — Login and receive JWT
• POST /auth/forgot-password — Request password reset
• POST /auth/reset-password — Reset password

Users

• GET /users/:id — Get user by ID (JWT required)

Wallet

• GET /wallet/balance — Get wallet balance (JWT required)
• POST /wallet/fund — Fund wallet (JWT required)

Transactions

• POST /transactions/transfer — Transfer funds to another user (JWT required)

Payment

• POST /payment — Initiate payment via provider (JWT required)

API Docs

• Swagger UI: http://localhost:3000/api

Security & Best Practices

• Input validation with DTOs and class-validator
• JWT authentication and guards
• Helmet for HTTP security headers
• Environment-based configuration
• Error handling and logging
• Rate limiting (recommended for production)

Contributing

Pull requests are welcome! Please open an issue first to discuss major changes.

License

MIT