Tutorial: FastAPI

This tutorial is AI-generated! To learn more, check out AI Codebase Knowledge Builder

FastAPI^{View Repo} is a modern, high-performance web framework for building APIs with Python. It’s designed to be easy to use, fast to code, and ready for production. Key features include automatic data validation (using Pydantic), dependency injection, and automatic interactive API documentation (OpenAPI and Swagger UI).

flowchart TD
    A0["FastAPI Application & Routing"]
    A1["Path Operations & Parameter Declaration"]
    A2["Data Validation & Serialization (Pydantic)"]
    A3["Dependency Injection"]
    A4["OpenAPI & Automatic Docs"]
    A5["Error Handling"]
    A6["Security Utilities"]
    A7["Background Tasks"]
    A0 -- "Defines Routes for" --> A1
    A1 -- "Uses for parameter/body val..." --> A2
    A1 -- "Uses Depends() for dependen..." --> A3
    A0 -- "Generates API spec for" --> A4
    A0 -- "Manages global" --> A5
    A3 -- "Injects BackgroundTasks object" --> A7
    A6 -- "Uses Depends mechanism (Sec..." --> A3
    A6 -- "Raises HTTPException on fai..." --> A5
    A4 -- "Reads definitions from" --> A1
    A4 -- "Reads Pydantic models for s..." --> A2
    A4 -- "Reads security scheme defin..." --> A6
    A5 -- "Handles RequestValidationEr..." --> A2

---

Table of contents

• FastAPI Application & Routing
• Path Operations & Parameter Declaration
• Data Validation & Serialization (Pydantic)
• OpenAPI & Automatic Docs
• Dependency Injection
• Error Handling
• Security Utilities
• Background Tasks