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FastAPI Framework

This file provides comprehensive guidance on using FastAPI for building modern APIs.

What is FastAPI?​

FastAPI is a modern, fast web framework for building APIs with Python 3.7+ based on standard Python type hints.

Key Features​

  • Fast: Very high performance, on par with NodeJS and Go
  • Fast to code: Increase the speed of developing features by about 200% to 300%
  • Fewer bugs: Reduce about 40% of human induced errors
  • Intuitive: Great editor support with autocompletion
  • Easy: Designed to be easy to use and learn
  • Short: Minimize code duplication

Basic Example​

from fastapi import FastAPI

app = FastAPI()

@app.get("/")
async def read_root():
    return {"Hello": "World"}

@app.get("/items/{item_id}")
async def read_item(item_id: int, q: str = None):
    return {"item_id": item_id, "q": q}

Advanced Features​

  • Automatic API documentation (Swagger UI)
  • Data validation using Pydantic
  • Dependency injection system
  • Authentication and authorization
  • Background tasks
  • WebSocket support

Best Practices​

  • Use type hints consistently
  • Implement proper error handling
  • Structure your application with routers
  • Use dependency injection for shared logic
  • Implement comprehensive testing

Resources​