Backend Authentication Implementation

Backend Authentication Implementation

• The backend folder structure includes controllers, routes, models, utils, and connections for better organization.

authController.ts

• Functions for user registration, authentication, and logout are defined but incomplete.
• Exports three main functions: registerUser, authenticateUser, and logoutUser.

authRouter.ts

• Uses Express Router to handle specific routes.
• Includes POST routes for registration, login, and logout.
• Controllers are imported from authController.ts.

index.ts

• Sets up the Express application to listen on a specified port (defaults to 3000).
• Imports and uses authRouter to handle authentication-related endpoints.
• Initializes database connection with connectUserDB.

Dependency Installation

• Installs jsonwebtoken for handling JWT tokens and bcryptjs for password hashing.
• Installs type definitions for the above libraries via @types/bcryptjs and @types/jsonwebtoken.
• Uses mongoose for MongoDB operations.

User Model (User.ts)

• Defines IUser interface with properties: name, email, password, and a method to compare passwords.
• Implements a userSchema that includes validation and password hashing before saving to the database.

Auth Functions Implementation

• registerUser checks for existing users, creates a new user, and generates a JWT token on successful registration.
• authenticateUser verifies user credentials and generates a JWT if valid.
• logoutUser clears the JWT cookie from the client.

JWT Token Management (auth.ts)

• Functions: generateToken for creating JWT tokens and setting security cookies, and clearToken for clearing cookies upon logout.
• Tokens expire in one hour.

MongoDB Connection (userDB.ts)

• Connects to MongoDB and logs the connection status or errors encountered during the connection process.

Environment Variables

• .env file includes:
  • PORT for server port
  • JWT_SECRET for signing JWT
  • NODE_ENV for environment type
  • MONGODB_URI for MongoDB connection string.
• Uses dotenv to load environment variables into the application.

Middleware Integration

• Installs body-parser for parsing incoming JSON requests.
• Installs cors to manage cross-origin requests and sets up middleware for allowed origins.
• Adds helmet for enhancing API security through setting response headers.

Custom Middleware for Authentication

• Middleware checks token validity before allowing access to certain user-specific routes.
• Exposes user routes under /users, ensuring only authenticated requests proceed.

Security Enhancements

• Additional security packages like helmet are employed to enhance response security headers.
• Properly handles user data by requiring token verification prior to accessing user profiles.

Application Testing

• Use tools like Postman to test API functionalities.
• Troubleshoot CORS issues that may arise due to domain mismatches during frontend and backend interactions.