FastAPI

Overview

FastAPI is built on Starlette (ASGI) and Pydantic v2. Path operation functions declare their inputs with type hints (path, query, header, body); FastAPI validates them, returns 422 with details on bad input, serialises the return value through response_model, and serves interactive docs at /docs (Swagger UI) and /redoc plus the schema at /openapi.json. The code below was run with fastapi 0.162.0, Starlette 1.10, Pydantic 2.14 and pytest 9.

Instructions

1. Install and layout

python -m venv .venv && source .venv/bin/activate
pip install "fastapi[standard]"      # adds the fastapi CLI, uvicorn, httpx, email-validator