JWT API Authentication

Overview

JWT (JSON Web Token) is a standard for securing API endpoints and managing user authentication and authorization. JWTs are compact tokens that encode claims and are cryptographically signed to ensure integrity and authenticity.

How JWT Authentication Works

1. User Registration: User provides credentials (username, email, password, role).
2. User Login: User logs in; backend generates and returns a JWT token.
3. Token Usage: Client stores the JWT and includes it in the Authorization header as a Bearer token for API requests.
4. Backend Authorization: Backend validates the JWT on each request, granting or denying access based on token validity.

Example JWT Authentication Flow

1. Register:

   POST /api/register
   {
     "username": "user1",
     "password": "password123"
   }
   

2. Login:

   POST /api/login
   {
     "username": "user1",
     "password": "password123"
   }
   // Response:
   {
     "token": "<JWT_TOKEN>"
   }
   

3. Access Protected Endpoints:

   • Use the JWT token in the Authorization header for subsequent API requests.

Benefits of JWT Authentication

• Stateless and scalable (no server-side session storage)
• Secure (signed and optionally encrypted tokens)
• Flexible (supports custom claims)
• Interoperable across platforms and services