Learning FastAPI from Scratch: Quickly Understanding the Core Concepts of API Development

API serves as a bridge for communication between different software systems. As a Python web framework, FastAPI has gained popularity due to its advantages such as simplicity, high performance, automatic API documentation generation, type hint support, and async-friendliness. Quick Start: After installing FastAPI and Uvicorn, write a main.py to define routes (e.g., @app.get("/")), then run Uvicorn to access the interface and return JSON data. Core concepts include: routes (URLs mapped to handler functions), HTTP request methods (GET for data retrieval, POST for data submission), three data handling methods (path parameters, query parameters, request bodies), and data validation (auto-validation via Pydantic models). Interactive documentation is automatically generated via Swagger UI (/docs) and ReDoc (/redoc). After mastering the basics, advanced learning can focus on asynchronous development, middleware, and database integration.