User Authentication System

A secure user authentication system built with Node.js, Express, MongoDB, and JWT (JSON Web Tokens).

Screenshots

Main Page - User Registration

Login Page

Features

• User registration and login
• Password hashing with bcrypt
• JWT-based authentication
• MongoDB database integration
• CORS support
• Environment variable configuration

Technologies Used

• Node.js - JavaScript runtime
• Express.js - Web application framework
• MongoDB - NoSQL database
• Mongoose - MongoDB object modeling
• JWT (jsonwebtoken) - Token-based authentication
• bcrypt - Password hashing
• dotenv - Environment variable management
• CORS - Cross-Origin Resource Sharing

Prerequisites

Before running this project, make sure you have:

• Node.js (v14 or higher)
• MongoDB installed and running
• npm or yarn package manager

Installation

1. Clone the repository:

git clone https://github.com/KUNDANIOS/user-auth-system-.git
cd user-auth-system-

2. Install dependencies:

npm install

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

JWT_SECRET=your-secret-key-change-in-production
JWT_EXPIRY=24h
MONGODB_URI=mongodb://localhost:27017/auth-system
PORT=5000

4. Update the configuration values:

   • Replace JWT_SECRET with a strong, unique secret key
   • Update MONGODB_URI with your MongoDB connection string
   • Adjust PORT if needed

5. Make sure MongoDB is running on your system

Running the Application

Start the server:

npm start

For development with auto-restart:

npm run dev

The server will start on http://localhost:5000 (or your specified PORT).

Testing the Application

Method 1: Using the HTML Interface

1. Open your browser and go to http://localhost:5000
2. You'll see the authentication interface
3. Try registering a new user and then logging in

Method 2: Using API Testing Tools (Postman, Thunder Client, or cURL)

Test Registration:

curl -X POST http://localhost:5000/api/auth/register \
  -H "Content-Type: application/json" \
  -d '{"username":"testuser","email":"test@example.com","password":"Test123456"}'

Test Login:

curl -X POST http://localhost:5000/api/auth/login \
  -H "Content-Type: application/json" \
  -d '{"email":"test@example.com","password":"Test123456"}'

Test Protected Route (use token from login response):

curl -X GET http://localhost:5000/api/auth/profile \
  -H "Authorization: Bearer YOUR_JWT_TOKEN_HERE"

Expected Responses

Successful Registration:

{
  "message": "User registered successfully",
  "userId": "507f1f77bcf86cd799439011"
}

Successful Login:

{
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",
  "user": {
    "id": "507f1f77bcf86cd799439011",
    "username": "testuser",
    "email": "test@example.com"
  }
}

API Endpoints

Authentication

Register User

POST /api/auth/register
Content-Type: application/json

{
  "username": "string",
  "email": "string",
  "password": "string"
}

Login User

POST /api/auth/login
Content-Type: application/json

{
  "email": "string",
  "password": "string"
}

Get User Profile (Protected)

GET /api/auth/profile
Authorization: Bearer <token>

Project Structure

user-auth-system/
├── node_modules/
├── .env
├── .gitignore
├── package.json
├── package-lock.json
├── server.js
├── index.html
└── README.md

Security Features

• Passwords are hashed using bcrypt with salt rounds
• JWT tokens for stateless authentication
• Environment variables for sensitive data
• CORS configuration for cross-origin requests

Environment Variables

Variable	Description	Default
JWT_SECRET	Secret key for JWT signing	Required
JWT_EXPIRY	Token expiration time	24h
MONGODB_URI	MongoDB connection string	Required
PORT	Server port number	5000

Contributing

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

License

This project is licensed under the MIT License.

Author

KUNDANIOS

Acknowledgments

• Express.js documentation
• MongoDB documentation
• JWT.io for token debugging
• bcrypt library for secure password hashing