How to gracefully stop FastAPI app ?

Hi All,

I just learn FastAPI and here is a very basic question raised here: How to gracefully stop FastAPI app ? We know “graceful stop” is a very critical concept in the modern web application. “Graceful stop” could help us avoid losing any request/data on the fly if we restart or stop apps, especially in rolling update. Many other frameworks, such as Go and Springboot consists of the solution to support “graceful stop”. But I searched around the Forum and Google but I didn’t find in detail how to do it in FastAPI app. I just notice there is a parameter “graceful_timeout” in “gunicorn” from https://github.com/tiangolo/uvicorn-gunicorn-fastapi-docker#graceful_timeout . But I am starting FastAPI by the following “uvicorn” instead of “gunicorn” command in my own docker (not official uvicorn-gunicorn-fastapi-docker):

uvicorn.run("app:app",host='0.0.0.0', port=8000, reload=True, debug=True, workers=3)

So I am not sure whether graceful stop is also supported in “uvicorn”. Is there a general solution we could gracefully stop FastAPI APP ?

Thank you !

Issue Analytics

State:
Created 3 years ago
Reactions:5
Comments:9 (5 by maintainers)

Top GitHub Comments

3reactions

raphaelauvcommented, Apr 17, 2021

Nobody put --reload on production ( dockerize or not ) deployment . Since it’s not a fastAPI issue, I propose that you close the issue.

3reactions

Halkcyoncommented, Mar 12, 2021

It might be helpful to point out that uvicorn recommends using gunicorn with a uvicorn worker in a production deployment (aka, not localhost)

https://www.uvicorn.org/deployment/#gunicorn

$ gunicorn -w 4 -k uvicorn.workers.UvicornWorker

I personally use a gunicorn configuration file instead of the cli (note: 20.1.x is not on pypi yet, so I’ve pinned this doc to its latest release)

https://docs.gunicorn.org/en/20.0.4/configure.html#configuration-file

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