Posts tagged: fastapi

Great list of 4 tips for running fastapi applications. Keep routes small # Fat routers with all of the logic built in makes them hard to test, hard to refactor, causes lots of duplication, and makes it hard to reuse the business logic code later in something like a cli application. Deploy Early # I really like this advice! He reccommends deploying as early as you can get a healthcheck live in your application. I’ve found too many times developers build something that is really hard, or impossible to deploy, when if they had tried to deploy early they would have spotted some easy to fix issues. This is less important if you are building out of a template that your team commonly deploys from, but very important with new patterns. https://youtu.be/XlnmN4BfCxw?si=ks1wvmgDyoQLgrv2&t=1093

Add a healthcheck to your FastAPI app | Nic Payne I'm building a few FastAPI apps to throw in docker and run on my homelab... I wanted to add healthchecks and here's a simple way to do it Make sure to pype.dev Nice example of adding a healthcheck to fastapi, and integrating it with docker. Don’t forget to include curl in the install, nice touch.

FastHX - FastHX volfpeter.github.io Very interesting approach to htmx and fast api. It uses separate decorators for returning template partials and json that can be stacked to include both options on a single route. The templates are explicitly set in the decorator. Separate decorators are used for full page and partial pages. I don’t see an example of full and partial pages being combined. I think the demo app must be behaving in a spa like fashion where it does not get all of the data when it calls index and index will ask for user-list. Definitely going to keep my eye on this project and ponder on it.

FastHX - FastHX volfpeter.github.io Very interesting approach to htmx and fast api. It uses separate decorators for returning template partials and json that can be stacked to include both options on a single route. The templates are explicitly set in the decorator. Separate decorators are used for full page and partial pages. I don’t see an example of full and partial pages being combined. I think the demo app must be behaving in a spa like fashion where it does not get all of the data when it calls index and index will ask for user-list. Definitely going to keep my eye on this project and ponder on it.

Background Tasks - FastAPI FastAPI framework, high performance, easy to learn, fast to code, ready for production fastapi.tiangolo.com fastapi comes with a concept of background tasks which are functions that can be ran in the background after a function has been ran. This is handy for longer running functions that may take some time and you want to have fast response times. Here is an example from the docs

Fields Pydantic Docs · docs.pydantic.dev and is a good pydantic combination for secret attributes such as user passwords, or hashed passwords. exclude keeps it out of model_dumps, and repr keeps it out of the logs.

Handling Errors - FastAPI FastAPI framework, high performance, easy to learn, fast to code, ready for production fastapi.tiangolo.com This page shows how to customize your fastapi errors. I found this very useful to setup common templates so that I can return the same 404’s both programatically and by default, so it all looks the same to the end user. This post sat in draft for months. I stumbled upon it again and found great success returning good error messages based on user preferences. the default remains json, but if a user requests it will be an html response, and text for or

![[None]] I’ve been using these decorators to modify the behavior of specific routes. It will do things like 404 admin only routes in a way that looks just like fastapi ’s default, or only allow certain roles into the route, or redirect unauthenticated users to login. After listening to yesterday’s syntaxfm I’m now really thinking about middleware and the benefits it might have. middleware would make it easy to apply things like admin to an entire admin router, so you wont forget it on any one admin route. It will look cleaner as the admin checker is only applied once per router, not once per route.

![[None]] jinja’s in fastapi does not account for https by default, there is probably a better way, but this is a way that allows me to configure when I use http vs https.

External Link stackoverflow.com After struggling to get dependencies inside of middleware I learned that you can make global dependencies at the app level. I used this to set the user on every single route of the application without needing Depend on getting the user on each route.

Handling Errors - FastAPI FastAPI framework, high performance, easy to learn, fast to code, ready for production fastapi.tiangolo.com This page shows how to customize your fastapi errors. I found this very useful to setup common templates so that I can return the same 404’s both programatically and by default, so it all looks the same to the end user.

logs with FastAPI and Uvicorn · Issue #1508 · fastapi/fastapi Hello, Thanks for FastAPI, easy to use in my Python projects! However, I have an issue with logs. In my Python project, I use: app = FastAPI() uvicorn.run(app, host="0.0.0.0", port=8000) And when... GitHub · github.com Setting an additional log handler to the uvicorn logger for access logs in fastapi was not straightforward, but This post was very helpful.

External Link stackoverflow.com Here is a full example from the post.

Path Operation Advanced Configuration - FastAPI FastAPI framework, high performance, easy to learn, fast to code, ready for production fastapi.tiangolo.com From the Docs # trailing slash # I’ve had better luck just routing both naked and trailing slash routes in fastapi. I’ve had api’s deployed as a subroute to a site rather than a subdomain, and the automatic redirect betweens them tended to always get messed up. This is pretty easy fix for the pain is causes just give vim a yyp, and if you don’t want deuplicates in your docs, ignore one. favicon.ico # Now you do not need to deploy favicons to your api in any way, it is nice to have it in your browser tab, but more importantly to me I hate having console errors that are meaningless, this gives the browser something to automatically grab and not log errors.

Protect API docs behind authentication? · Issue #364 · fastapi/fastapi Basic Question Does FastAPI provide a method for implementing authentication middleware or similar on the docs themselves (e.g. to protect access to /docs and /redoc)? Additional context My company... GitHub · github.com You can protect your fastapi docs behind auth so that not only can certain roles not run certain routes, but they cannot even see the docs at all. This way no one that shouldn’t be poking around can even discover routes they shouldn’t be using. Here is the soluteion provided by @kennylajara

Sebastián Ramírez (@tiangolo) on X Now @FastAPI has 65k+ GitHub stars! ✨🎉 Since today, FastAPI has a few more GitHub stars than Flask. 🤯 Now FastAPI is the second most starred Python web framework, right after Django. 🥈 X (formerly Twitter) · twitter.com Fastapi passes flask in GitHub stars!

GitHub - florimondmanca/arel: Lightweight browser hot reload for Python ASGI web apps Lightweight browser hot reload for Python ASGI web apps - florimondmanca/arel GitHub · github.com arel is a “Lightweight browser hot reload for Python ASGI web apps” I just implemented this on my thoughts website using fastapi, and it’s incredibly fast and lightweight. There just two lines of js that make a web socket connection back to the backend that watches for changes. When in development mode, this snippet gets injected directly on the page and does a refresh when arel detects a change.

main.py python I just discovered arel for hot reloading python applications when content changes from this snippet that implements it for fatapi. On app startup add the routes if in DEBUG mode. install and make sure you have for websocket support. In the template, load the script when in debug mode.

Bigger Applications - Multiple Files - FastAPI FastAPI framework, high performance, easy to learn, fast to code, ready for production fastapi.tiangolo.com Fastapi lets you tag your ’s so that the swagger docs are grouped according to the router. Now all routes in will appear in the router group in the swagger docs.

Create Models with a Many-to-Many Link - SQLModel SQLModel, SQL databases in Python, designed for simplicity, compatibility, and robustness. sqlmodel.tiangolo.com Creating many to many relationships with sqlmodel requires a LinkTable Model. The link model will keep track of the linked id’s between each of the models.