FinTrack Backend Service

A modular, production-ready Node.js & Express REST API architecture for FinTrack.

📁 Directory Structure

Backend/
├── .env                  # Local environment variables
├── .env.example          # Environment variables template
├── .gitignore            # Git ignore configuration
├── package.json          # Dependencies & npm scripts
├── Readme.md             # Project documentation
└── src/
    ├── app.js            # Express app configuration & middleware setup
    ├── server.js         # Entry point & server bootstrapping
    ├── config/           # Environment and DB configuration
    │   ├── db.js
    │   └── env.js
    ├── controllers/      # Request handlers / Controllers
    │   ├── auth.controller.js
    │   ├── health.controller.js
    │   └── transaction.controller.js
    ├── middlewares/      # Express custom middlewares (Auth, Errors, Validation)
    │   ├── auth.middleware.js
    │   └── error.middleware.js
    ├── models/           # Data models (Database schemas - Mongoose/Prisma)
    ├── routes/           # Express Route Definitions
    │   ├── index.js
    │   ├── auth.routes.js
    │   ├── health.routes.js
    │   └── transaction.routes.js
    ├── services/         # Business logic layer
    └── utils/            # Shared utilities & response helpers
        ├── apiResponse.js
        └── logger.js

🚀 Quick Start

1. Install Dependencies

   npm install

2. Configure Environment

   cp .env.example .env

3. Run Development Server

   npm run dev

4. Run Production Server

   npm start

🔌 API Routes (Base Endpoint: /api/v1)

Method	Endpoint	Description	Auth Required
GET	/api/v1/health	Service health check	No
POST	/api/v1/auth/register	Register user	No
POST	/api/v1/auth/login	User login	No
GET	/api/v1/auth/profile	Get current user profile	Yes
GET	/api/v1/transactions	List all transactions	Yes
POST	/api/v1/transactions	Create new transaction	Yes

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🧪 Development / Quality Checks

Install dependencies

npm install

Run linting

npm run lint

ESLint performs static analysis on the source code to catch bugs, enforce consistent style, and flag potential issues before they reach runtime. The configuration lives in eslint.config.js and targets all files under src/.

Run tests

npm test

Jest is the test runner. Tests live in the tests/ directory and follow the *.test.js naming convention.

Supertest is used alongside Jest to make real HTTP requests against the Express app without starting a live server. It imports src/app.js directly, keeping tests fast and self-contained.

Test structure

tests/
└── health.test.js   # Integration test for GET /api/v1/health

Note: Because the project uses ES Modules ("type": "module"), Jest is run with the --experimental-vm-modules flag automatically via the npm test script. No Babel configuration is needed.