to build something cool quickly and go to production in some hours

🧠 From a basic to advanced thinking only register user

Area	Focus
Edge cases	Re-registering with same email, missing fields
Security	Rate limiting, CAPTCHA, timing attacks
Scalability	Async DB writes, background tasks for emails
Maintainability	Is your logic testable and reusable?
Clean architecture	Are you separating layers (API, service, DB)?
Error handling	Are you raising proper exceptions with status codes?
Auditing	Should you log registrations? Add metrics?

│ │ ├── init.py │ │ └── v1/ # API version 1 │ │ ├── init.py │ │ └── user.py # User endpoints (register, login, profile) │ ├── core/ # Core functionality and utilities │ │ ├── init.py │ │ ├── config.py # Configuration settings │ │ ├── security.py # JWT tokens, password hashing │ │ └── validate.py # Input validation utilities │ ├── models/ # Database models (Beanie ODM) │ │ ├── init.py │ │ └── user.py # User document model │ ├── schemas/ # Pydantic schemas (request/response) │ │ ├── init.py │ │ ├── auth.py # Authentication schemas │ │ └── user.py # User request/response schemas │ └── services/ # Business logic layer │ ├── init.py │ └── user_service.py # User business logic ├── tests/ # Test suite │ ├── init.py │ ├── test_api.py # API endpoint tests │ ├── test_models.py # Database model tests │ ├── test_schemas.py # Schema validation tests │ └── test_validate.py # Validation utility tests ├── docker-compose.yml # Docker services configuration ├── Dockerfile # Application container ├── requirements.txt # Python dependencies ├── pytest.ini # Test configuration ├── .env.example # Environment variables template └── README.md # This file

## 🚀 Quick Start

### Prerequisites

- Python 3.8+
- MongoDB 4.4+
- Docker & Docker Compose (optional)

### Installation

1. **Clone the repository**
   ```bash
   git clone <repository-url>
   cd python-fastapi-service

2. Create virtual environment

   python -m venv venv
   source venv/bin/activate  # On Windows: venv\Scripts\activate

3. Install dependencies

   pip install -r requirements.txt

4. Set up environment variables

   cp .env.example .env
   # Edit .env with your configuration

5. Start MongoDB (if not using Docker)

   # Using Docker
   docker run -d -p 27017:27017 --name mongodb mongo:latest
   
   # Or install MongoDB locally
   # https://docs.mongodb.com/manual/installation/

6. Run the application

   uvicorn app.main:app --reload --host 0.0.0.0 --port 8000

Using Docker Compose

# Start all services (app + MongoDB)
docker-compose up -d

# View logs
docker-compose logs -f

# Stop services
docker-compose down

📖 API Documentation

Once the server is running, visit:

• Swagger UI: http://localhost:8000/docs
• ReDoc: http://localhost:8000/redoc
• OpenAPI JSON: http://localhost:8000/openapi.json

🔗 API Endpoints

Authentication

Method	Endpoint	Description	Auth Required
POST	/users/register	Register new user	❌
POST	/users/login	User login	❌
GET	/users/me	Get current user profile	✅
GET	/users/	List users (admin only)	✅

Example Requests

Register User

curl -X POST "http://localhost:8000/users/register" \
  -H "Content-Type: application/json" \
  -d '{
    "username": "john_doe",
    "email": "[email protected]",
    "password": "SecurePass123!"
  }'

Login User

curl -X POST "http://localhost:8000/users/login" \
  -H "Content-Type: application/json" \
  -d '{
    "email": "[email protected]",
    "password": "SecurePass123!"
  }'

🧪 Testing

Run All Tests

pytest

Run Specific Test Categories

# Unit tests only
pytest tests/test_validate.py -v

# API tests only
pytest tests/test_api.py -v

# With coverage
pytest --cov=app tests/

Test Structure

• test_validate.py: Validation utility tests
• test_schemas.py: Pydantic schema tests
• test_models.py: Database model tests
• test_api.py: API endpoint integration tests

⚙️ Configuration

Environment Variables

Create a .env file with the following variables:

# Database
MONGO_URL=mongodb://localhost:27017
DATABASE_NAME=fastapi_service

# Security
SECRET_KEY=your-super-secret-key-here
ALGORITHM=HS256
ACCESS_TOKEN_EXPIRE_MINUTES=30

# Application
APP_NAME=FastAPI Service
APP_VERSION=1.0.0
DEBUG=false

# CORS
ALLOWED_ORIGINS=["http://localhost:3000", "http://localhost:8080"]

🔒 Security Features

Password Requirements

• Minimum 8 characters
• At least one uppercase letter
• At least one lowercase letter
• At least one number
• At least one special character
• No common weak patterns

Account Security

• Account locking after 5 failed login attempts
• JWT token-based authentication
• Password hashing with bcrypt
• Email validation with deliverability checks

Input Validation

• Comprehensive Pydantic schemas
• Custom validation functions
• SQL injection prevention
• XSS protection

🏗️ Architecture

Clean Architecture Principles

1. Separation of Concerns: Clear separation between API, business logic, and data layers
2. Dependency Inversion: High-level modules don't depend on low-level modules
3. Single Responsibility: Each module has a single, well-defined purpose
4. Open/Closed Principle: Open for extension, closed for modification

Layer Responsibilities

• API Layer (app/api/): HTTP request/response handling, routing
• Schema Layer (app/schemas/): Data validation and serialization
• Service Layer (app/services/): Business logic and orchestration
• Model Layer (app/models/): Data persistence and database operations
• Core Layer (app/core/): Shared utilities and configuration

📊 Database Schema

User Document

{
  "_id": ObjectId,
  "name": str,
  "email": str,  # Unique, indexed
  "hashed_password": str,
  "active": bool,
  "role": str,
  "created_at": datetime,
  "updated_at": datetime,
  "last_login": datetime,
  "login_attempts": int,
  "locked_until": datetime,
  "phone": str,
  "address": str,
  "profile_picture_url": str,
  "cover_picture_url": str
}

Indexes

• email: Unique index for fast user lookup
• active: Index for filtering active users
• role: Index for role-based queries
• created_at: Index for sorting by creation date

🚀 Deployment

Production Checklist

• Set strong SECRET_KEY in production
• Configure proper MongoDB connection string
• Set DEBUG=false
• Configure CORS origins
• Set up SSL/TLS certificates
• Configure logging levels
• Set up monitoring and health checks
• Configure backup strategy

Docker Production Deployment

# Build production image
docker build -t fastapi-service:latest .

# Run with production settings
docker run -d \
  --name fastapi-service \
  -p 8000:8000 \
  --env-file .env.production \
  fastapi-service:latest

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Make your changes
4. Add tests for new functionality
5. Ensure all tests pass (pytest)
6. Commit your changes (git commit -m 'Add amazing feature')
7. Push to the branch (git push origin feature/amazing-feature)
8. Open a Pull Request

Code Style

• Follow PEP 8 guidelines
• Use type hints
• Write docstrings for functions and classes
• Maintain test coverage above 90%
• Use meaningful variable and function names

📝 Development Notes

Adding New Endpoints

1. Create schema in app/schemas/
2. Add business logic in app/services/
3. Create API endpoint in app/api/v1/
4. Write tests in tests/
5. Update documentation

Database Migrations

For schema changes:

1. Update model in app/models/
2. Create migration script if needed
3. Test with sample data
4. Update tests

🐛 Troubleshooting

Common Issues

MongoDB Connection Issues

# Check if MongoDB is running
docker ps | grep mongo

# Check connection
mongo mongodb://localhost:27017

Import Errors

# Ensure you're in the virtual environment
source venv/bin/activate

# Install dependencies
pip install -r requirements.txt

Test Failures

# Run tests with verbose output
pytest -v

# Run specific test
pytest tests/test_api.py::TestUserRegistrationAPI::test_successful_registration -v

📚 Additional Resources

• FastAPI Documentation
• Beanie ODM Documentation
• Pydantic Documentation
• MongoDB Documentation
• pytest Documentation

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

👥 Authors

• Your Name - Initial work - YourGitHub

🙏 Acknowledgments

• FastAPI team for the amazing framework
• MongoDB team for the robust database
• Python community for excellent libraries

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Built with ❤️ using FastAPI, MongoDB, and Python