0x03-user_authentication_service

0x03-user_authentication_service

This repository contains a Flask-based user authentication service with SQLAlchemy as the ORM and bcrypt for password hashing. Below is an overview of each task implemented:

User Authentication Service - Project Overview

Project Structure

alx-backend-user-data/
└── 0x03-user_authentication_service/
    ├── app.py               # Flask application with all routes
    ├── auth.py              # Auth class with core authentication logic
    ├── db.py                # Database interaction class
    ├── user.py              # User model definition
    ├── main.py              # Integration test script
    └── README.md            # Project documentation

Key Features

1. User Management

   • Secure user registration with email/password
   • Password hashing using bcrypt
   • Unique email validation

2. Session Management

   • Session creation with UUID tokens
   • Session validation middleware
   • Secure logout functionality

3. Authentication Flow

   • Login with email/password
   • Protected routes requiring valid sessions
   • Profile access control

4. Password Recovery

   • Reset token generation
   • Secure password update flow
   • Token invalidation after use

5. Database Integration

   • SQLAlchemy ORM for database operations
   • SQLite database (can be configured for other DBMS)
   • User model with all required fields

Technical Stack

• Backend Framework: Flask
• Database ORM: SQLAlchemy
• Password Hashing: bcrypt
• Session Management: UUID tokens
• Testing: Python unittest via integration tests

API Endpoints

Endpoint	Method	Description
/	GET	Welcome message
/users	POST	Register new user
/sessions	POST	User login
/sessions	DELETE	User logout
/profile	GET	Get user profile
/reset_password	POST	Request password reset token
/reset_password	PUT	Update password with reset token

Security Features

• All passwords are hashed with bcrypt before storage
• Session tokens are randomly generated UUIDs
• No sensitive data exposed in API responses
• Proper error handling for invalid requests
• CSRF protection via session tokens

How to Use

1. Setup:

   pip install -r requirements.txt

2. Run the server:

   python app.py

3. Run tests:

   python main.py

Example Usage

1. Register a user:

   curl -XPOST localhost:5000/users -d 'email=test@example.com' -d 'password=secure123'

2. Login:

   curl -XPOST localhost:5000/sessions -d 'email=test@example.com' -d 'password=secure123' -v

3. Access profile:

   curl -XGET localhost:5000/profile -b "session_id=<your_session_id>"

4. Reset password:

   # Request token
   curl -XPOST localhost:5000/reset_password -d 'email=test@example.com'
   
   # Update password
   curl -XPUT localhost:5000/reset_password -d 'email=test@example.com' -d 'reset_token=<token>' -d 'new_password=newsecure123'

This service provides a complete authentication solution that can be integrated into larger applications or used as a reference implementation for Flask-based authentication systems.

Task 0: User Model

• Created a SQLAlchemy model named User for a database table named users
• Attributes:
  • id: integer primary key
  • email: non-nullable string
  • hashed_password: non-nullable string
  • session_id: nullable string
  • reset_token: nullable string

Task 1: Create User

• Implemented add_user method in DB class
• Takes email and hashed_password as arguments
• Saves user to database and returns User object

Task 2: Find User

• Implemented find_user_by method in DB class
• Takes arbitrary keyword arguments to filter users
• Raises NoResultFound if no user found
• Raises InvalidRequestError for invalid query arguments

Task 3: Update User

• Implemented update_user method in DB class
• Takes user_id and arbitrary keyword arguments for updates
• Raises ValueError if invalid user attribute is passed

Task 4: Hash Password

• Implemented _hash_password method
• Takes password string, returns salted hash as bytes
• Uses bcrypt.hashpw for hashing

Task 5: Register User

• Implemented register_user in Auth class
• Takes email and password, hashes password
• Raises ValueError if user already exists
• Returns created User object

Task 6: Basic Flask App

• Created basic Flask app with single GET route "/"
• Returns JSON: {"message": "Bienvenue"}

Task 7: Register User Endpoint

• Implemented POST /users route
• Registers new user with email and password
• Returns 400 if email already registered

Task 8: Credentials Validation

• Implemented valid_login method in Auth class
• Checks email and password against database
• Returns True if valid, False otherwise

Task 9: Generate UUIDs

• Implemented _generate_uuid helper function
• Returns string representation of new UUID

Task 10: Get Session ID

• Implemented create_session method in Auth class
• Generates session ID for user and stores in database
• Returns session ID string

Task 11: Login Endpoint

• Implemented POST /sessions route
• Validates login credentials
• Sets session_id cookie on successful login
• Returns 401 for invalid credentials

Task 12: Find User by Session

• Implemented get_user_from_session_id method
• Returns User object for valid session ID
• Returns None for invalid/expired sessions

Task 13: Destroy Session

• Implemented destroy_session method
• Updates user's session_id to None

Task 14: Logout Endpoint

• Implemented DELETE /sessions route
• Destroys session based on session_id cookie
• Redirects to home page or returns 403

Task 15: Profile Endpoint

• Implemented GET /profile route
• Returns user email for valid session
• Returns 403 for invalid session

Task 16: Reset Password Token

• Implemented get_reset_password_token method
• Generates and stores reset token for user
• Raises ValueError for invalid email

Task 17: Reset Token Endpoint

• Implemented POST /reset_password route
• Generates reset token for valid email
• Returns 403 for invalid email

Task 18: Update Password

• Implemented update_password method
• Updates password using reset token
• Raises ValueError for invalid token

Task 19: Update Password Endpoint

• Implemented PUT /reset_password route
• Updates password with email, token and new password
• Returns 403 for invalid token

Task 20: End-to-end Integration Test

• Created test script that exercises all endpoints
• Tests registration, login, profile access, logout, and password reset
• Uses assertions to validate responses

The service provides a complete authentication flow with user registration, session management, and password reset functionality.