💓 Lifeline API

A secure and scalable backend API for user authentication built using Node.js, Express.js, and MongoDB.

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🚀 Features

• User Registration & Login (JWT Auth)
• Passwords hashed with bcryptjs
• Token-based protected routes
• Input validation using express-validator
• Secure headers with helmet
• CORS enabled for frontend integration
• Logging with morgan
• Rate limiting to prevent brute-force attacks

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🛠️ Tech Stack

Technology	Purpose
Node.js	JavaScript runtime
Express.js	Web framework
MongoDB	NoSQL database
Mongoose	ODM for MongoDB
bcryptjs	Hash passwords securely
jsonwebtoken	JWT-based authentication
dotenv	Environment variable handling
helmet	Set secure HTTP headers
cors	Allow cross-origin requests
morgan	Request logging in dev mode
nodemon	Auto-restart during development

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📦 Installation

git clone https://github.com/your-username/lifeline-api.git
cd lifeline-api
npm install

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🔐 Environment Setup

Create a .env file:

PORT=5000
MONGODB_URI=your_mongodb_connection_string
JWT_SECRET=your_jwt_secret_key

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⚙️ Running the Server

# Development
npm run dev

# Production
npm start

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📌 API Endpoints

🔹 Register

POST /register
Body:

{
  "name": "Balaji",
  "email": "balaji@example.com",
  "password": "yourPassword"
}

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🔹 Login

POST /login
Body:

{
  "email": "balaji@example.com",
  "password": "yourPassword"
}

Response:

{
  "token": "your_jwt_token"
}

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✅ How It Works (Flow Diagram)

1. register() → Saves user with hashed password
2. login() → Verifies password → Sends back JWT
3. authMiddleware → Validates token → Grants access
4. Protected Routes → Read req.user from decoded token

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👨‍💻 Author

• Balaji
• GitHub

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🛡️ License

This project is licensed under the ISC License.

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