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Real-World Examples

User Authentication System

Build a complete authentication flow with registration, login, logout, token refresh, and password reset.

What You'll Build

Authentication Features

  • • User registration with validation
  • • Email/password login
  • • JWT token-based authentication
  • • Access & refresh token flow
  • • Logout functionality
  • • Password reset via email
  • • Email verification
  • • Session management

What You'll Learn

  • • JWT token generation & validation
  • • Secure password storage (hashing)
  • • Token refresh patterns
  • • Authentication middleware
  • • Password reset flows
  • • Email verification patterns
  • • Security best practices
  • • Error handling for auth

Time Required

⏱️ Approximately 60-90 minutes

Step 1: Create Auth API Project

Set Up Authentication Project
1

Create New Project

Project Name: Auth API
2

Note Project Slug

Copy your project slug (e.g., proj_auth_xyz123)

Step 2: Define User Schema

User Data Structure

Create a /users endpoint with this schema:

json

⚠️ Note: In production, you'd never expose the password hash. This is a mock API for frontend development.

Step 3: User Registration

POSTRegister New User

Endpoint:

POST /api/proj_auth_xyz/auth/register

Request Body

json

Validation Rules

  • • Email must be valid and unique
  • • Password minimum 8 characters, include uppercase, lowercase, number, special char
  • • Username 3-20 characters, alphanumeric and underscore only
  • • First name and last name required

Success Response (201 Created)

json

Error Response (422 Validation Error)

json

Step 4: User Login

POSTLogin Endpoint

Endpoint:

POST /api/proj_auth_xyz/auth/login

Request Body

json

Success Response (200 OK)

json

Error Response (401 Unauthorized)

json

Token Types

  • Access Token: Short-lived (15-60 min), used for API requests
  • Refresh Token: Long-lived (7-30 days), used to get new access tokens

Step 5: Token Refresh

Refresh Access Token

Endpoint:

POST /api/proj_auth_xyz/auth/refresh

Request Body

json

Success Response (200 OK)

json

Error Response (401 Unauthorized)

json

When to Refresh

Automatically refresh the access token before it expires, or when you receive a 401 response. This keeps the user logged in seamlessly.

Step 6: Get Current User

GETGet Authenticated User Profile

Endpoint:

GET /api/proj_auth_xyz/auth/me

Request Headers

plaintext

Success Response (200 OK)

json

Error Response (401 Unauthorized)

json

Step 7: User Logout

POSTLogout User

Endpoint:

POST /api/proj_auth_xyz/auth/logout

Request Headers

plaintext

Request Body (Optional)

json

Success Response (200 OK)

json

Client-side: Also clear tokens from local storage/cookies and redirect to login page.

Step 8: Password Reset Flow

Request Password Reset

Endpoint:

POST /api/proj_auth_xyz/auth/forgot-password

Request Body

json

Success Response (200 OK)

json

Security: Always return success even if email doesn't exist (prevents email enumeration attacks).

Reset Password with Token

Endpoint:

POST /api/proj_auth_xyz/auth/reset-password

Request Body

json

Success Response (200 OK)

json

Error Response (400 Bad Request)

json

Step 9: Email Verification

Send Verification Email

Endpoint:

POST /api/proj_auth_xyz/auth/send-verification

Request Headers

plaintext

Success Response (200 OK)

json
Verify Email with Token

Endpoint:

POST /api/proj_auth_xyz/auth/verify-email

Request Body

json

Success Response (200 OK)

json

Step 10: Frontend Integration

React Authentication Hook
javascript

Usage Examples

Login Component
javascript
Registration Component
javascript

Security Best Practices

Important Security Considerations
Store tokens securely: Use httpOnly cookies in production, not localStorage
Always use HTTPS: Never send tokens over unencrypted connections
Implement rate limiting: Prevent brute force attacks on login/register
Hash passwords: Use bcrypt/argon2, never store plain text
Validate input: Sanitize and validate all user input
Use short token expiry: 15-60 min for access tokens
Implement CSRF protection: For cookie-based authentication
Log security events: Monitor failed login attempts
Add 2FA: Multi-factor authentication for enhanced security
Environment variables: Never hardcode secrets or API keys
Congratulations! 🎉

You've built a complete authentication system with:

User registration with validation
Email/password login
JWT token authentication
Access & refresh token flow
Password reset functionality
Email verification
Logout capability
React integration with hooks

This forms the foundation for secure user management in your applications!

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