Uvicorn can not start FastAPI APP

See original GitHub issue

import uvicorn
from fastapi import FastAPI
app = FastAPI(title='MADS API')
uvicorn.run(app, host='0.0.0.0', port=8127, workers=2)
WARNING:  You must pass the application as an import string to enable 'reload' or 'workers'.

(Than it quits with System Code 1)

Versions:

$ pip3 list |grep "uvicorn\|fastapi"
fastapi                          0.55.1       
uvicorn                          0.11.5

Ubuntu 20.04; python 3.8.2

Issue Analytics

State:
Created 3 years ago
Comments:5 (1 by maintainers)

Top GitHub Comments

9reactions

dhendocommented, Jun 1, 2020

It’ll depend on the file name - if for example it was called server.py then the string you should use is "server:app"

2reactions

dhendocommented, May 29, 2020

I think you need to pass the app as a string, rather than directly, as you’ve passed the workers argument.

uvicorn.run("your_module_name:app", host='0.0.0.0', port=8127, workers=2)

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