CHAPTER 01 / 08
Routing and HTTP methods
Create your first FastAPI app and run it locally. Python examples show path parameters, route ordering, and GET, POST, PUT, and DELETE.
Python reference
FastAPI
cheat sheet.
Routes, Pydantic validation, dependencies, database sessions, authentication, testing, and deployment with FastAPI.
28 topics53 code examplesUpdated
How FastAPI fits together
01Request arrivesA client chooses a URL and method.
02Data validatesTypes and Pydantic parse inputs.
03Function runsDependencies supply what it needs.
04Response returnsSchema filters output; JSON leaves.
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8 chapters · 28 topics
CHAPTER 02 / 08
Validation, dependencies, and responses
Validate FastAPI requests with Pydantic, inject dependencies with Depends, and return response models. Includes APIRouter and async handlers.
7 topics
CHAPTER 03 / 08
SQLAlchemy and database sessions
Use SQLAlchemy with FastAPI for models, session dependencies, queries, and transactions. Includes relationship loading and async sessions.
CHAPTER 04 / 08
Authentication and authorization
Add password hashing, bearer JWT authentication, and OAuth2 scopes to FastAPI. Examples explain roles, ownership checks, and token handling.
CHAPTER 05 / 08
Testing, middleware, and uploads
Test FastAPI routes with dependency overrides and async fixtures. Configure CORS and middleware, upload files, and return downloads.
CHAPTER 06 / 08
Lifespan, background tasks, and WebSockets
Manage FastAPI startup and shutdown with lifespan, schedule background tasks, and serve WebSockets or event streams. Includes OpenAPI examples.
CHAPTER 07 / 08
Deployment and performance
Deploy FastAPI behind a reverse proxy, size worker processes and database pools, and handle timeouts, health checks, and blocking work.
CHAPTER 08 / 08
Patterns, pitfalls, and reference
Look up FastAPI terms and common mistakes: blocking async handlers, leaking database sessions, response validation, and background jobs.
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