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description: FastAPI best practices and patterns for building modern Python web APIs globs: /*.py, app//.py, api/**/.py

FastAPI Best Practices

Project Structure

• Use proper directory structure
• Implement proper module organization
• Use proper dependency injection
• Keep routes organized by domain
• Implement proper middleware
• Use proper configuration management

API Design

• Use proper HTTP methods
• Implement proper status codes
• Use proper request/response models
• Implement proper validation
• Use proper error handling
• Document APIs with OpenAPI

Models

• Use Pydantic models
• Implement proper validation
• Use proper type hints
• Keep models organized
• Use proper inheritance
• Implement proper serialization

Database

• Use proper ORM (SQLAlchemy)
• Implement proper migrations
• Use proper connection pooling
• Implement proper transactions
• Use proper query optimization
• Handle database errors properly

Authentication

• Implement proper JWT authentication
• Use proper password hashing
• Implement proper role-based access
• Use proper session management
• Implement proper OAuth2
• Handle authentication errors properly

Security

• Implement proper CORS
• Use proper rate limiting
• Implement proper input validation
• Use proper security headers
• Handle security errors properly
• Implement proper logging

Performance

• Use proper caching
• Implement proper async operations
• Use proper background tasks
• Implement proper connection pooling
• Use proper query optimization
• Monitor performance metrics

Testing

• Write proper unit tests
• Implement proper integration tests
• Use proper test fixtures
• Implement proper mocking
• Test error scenarios
• Use proper test coverage

Deployment

• Use proper Docker configuration
• Implement proper CI/CD
• Use proper environment variables
• Implement proper logging
• Use proper monitoring
• Handle deployment errors properly

Documentation

• Use proper docstrings
• Implement proper API documentation
• Use proper type hints
• Keep documentation updated
• Document error scenarios
• Use proper versioning