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Notes

API​

Documentation​

FastAPI is carefully built around the OpenAPI Specification (formerly known as swagger) standards. In FastAPI, by coding your endpoints, you are automatically writing your API documentation. Under the hood, FastAPI maps your endpoint details to a JSON Schema document.

The generated documentation can (if given enough detail) display:

  • Path operations
  • Parameters
  • Body requests
  • Security details such as required headers

Validation​

Under the hood, FastAPI uses Pydantic for data validation. With Pydantic along with type hints, you get a nice editor experience with autocompletion. You also get data validation, serialization and deserialization (for building an API), and automatic documentation (via JSON Schema and OpenAPI).