fastapi

Structure routing and dependency injection in FastAPI by using modular routers for endpoint composition and injecting typed dependencies to handle shared logic. This pattern ensures your API remains scalable, testable, and cleanly organized across large codebases.

Validate data models and schemas in FastAPI by defining Pydantic models with strict type hints. This approach automatically handles request validation, serialization, and documentation, ensuring robust APIs with clear data contracts.

FastAPI supports WebSockets and background tasks for asynchronous operations, enabling real-time communication and deferred processing. These features allow you to handle long-running tasks without blocking main application threads.

Test FastAPI routing and dependency wiring by using built-in testing templates that validate endpoint behavior and injected dependencies. This ensures your application logic is verified before executing production deployment configurations.

These FastAPI patterns support building large-scale production APIs by providing battle-tested templates for modular routers, typed schemas, and asynchronous support. They meet requirements for scalable, high-performance web services.

Use dependency injection patterns in FastAPI when you need to share database sessions, enforce authentication, or reuse business logic across endpoints. This approach keeps your code modular, maintainable, and highly testable.