FastAPI cookbook

10 recipes · 66 steps · about 49 minutes of reading

Validate a request body with a Pydantic model
I wrote the route but I'm still hand-checking every field myself, and I know FastAPI is supposed to do this for me.
BeginnerRead 4 minDoing: half an hour, with your project open6 steps
Turn FastAPI's bare auto-generated OpenAPI docs into ones consumers can use
My frontend teammate keeps pinging me to ask what a field in my API actually means.
BeginnerRead 5 minDoing: an hour7 steps
Every API error looks different right now
Half my endpoints raise HTTPException. The other half just return a raw dict, and nothing matches.
Beginner to intermediateRead 5 minDoing: an hour, with your project open7 steps
Split a single main.py into routers organized by domain
main.py is nine hundred lines now and I can't find anything in it anymore.
Beginner to intermediateRead 6 minDoing: an afternoon8 steps
A CORS error blocks your frontend from calling this brand new API
Why does my React app get a CORS error the moment it tries to call my FastAPI backend?
IntermediateRead 5 minDoing: under an hour6 steps
One shared dependency instead of a check copied into every route
Copied into every route, again.
IntermediateRead 5 minDoing: an hour, with your project open7 steps
Limit how many rows a list endpoint returns at once
One test account has ten items and the list endpoint already returns all of them at once.
IntermediateRead 4 minDoing: under an hour, with your project open6 steps
Email new signups without blocking your response
The signup endpoint takes three seconds because it waits for the welcome email to send before it replies.
Intermediate to advancedRead 5 minDoing: an hour, with your project open7 steps
No shared ID across the log lines for one request
Same bug, two users, and no way to tell whose log lines are whose.
Intermediate to advancedRead 4 minDoing: about an hour, with your project open5 steps
Push live updates to a browser with a WebSocket instead of polling
My dashboard polls every couple of seconds and it still feels a beat behind.
Intermediate to advancedRead 6 minDoing: an afternoon, with your project open7 steps

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In these roadmaps

Backend Developerstep 5 of 15

FastAPI cookbook

Validate a request body with a Pydantic model

Turn FastAPI's bare auto-generated OpenAPI docs into ones consumers can use

Every API error looks different right now

Split a single main.py into routers organized by domain

A CORS error blocks your frontend from calling this brand new API

One shared dependency instead of a check copied into every route

Limit how many rows a list endpoint returns at once

Email new signups without blocking your response

No shared ID across the log lines for one request

Push live updates to a browser with a WebSocket instead of polling

In these roadmaps

FastAPI cookbook

Validate a request body with a Pydantic model

Turn FastAPI's bare auto-generated OpenAPI docs into ones consumers can use

Every API error looks different right now

Split a single main.py into routers organized by domain

A CORS error blocks your frontend from calling this brand new API

One shared dependency instead of a check copied into every route

Limit how many rows a list endpoint returns at once

Email new signups without blocking your response

No shared ID across the log lines for one request

Push live updates to a browser with a WebSocket instead of polling

In these roadmaps