Error during execution of console_scripts in setup.cfg

Question

While running the console_script entry point defined in setup.cfg I am getting the below error. not sure why its complaining about the positional args.

start-prediction-engine
Traceback (most recent call last):
  File "/usr/local/bin/start-prediction-engine", line 8, in <module>
    sys.exit(app())
TypeError: __call__() missing 3 required positional arguments: 'scope', 'receive', and 'send'

here is the content in setup.cfg file

[options.entry_points]
console_scripts =
  start-prediction-engine = prediction_engine.prediction_engine:app

in the file prediction_engine.py

if __name__ == "__main__":
    uvicorn.run("prediction_engine:app", host="0.0.0.0", port=8888, reload=True, log_level="info")

Answer 1

I fell into this same trap.

The issue is you're trying to register a console script to the app object (which I'm assuming is a FastAPI app instance).

Console scripts must be registered to a function. See the introduction here for more information.

To remedy this, you can simply create a function that runs your app:

# prediction_engine.py
def main():
    uvicorn.run("prediction_engine:app", host="0.0.0.0", port=8888, reload=True, log_level="info")

if __name__ == "__main__":
    sys.exit(main())

Adding the if __name__ == "__main__": section is unnecessary if you will always run from your console script, but this also lets you run it by doing i.e.

python prediction_engine.py

Finally, you'll want to point your console_script entry in your setup.cfg to the main() function:

# setup.cfg
[options.entry_points]
console_scripts =
  start-prediction-engine = prediction_engine.prediction_engine:main

Incidentally, the error you're getting

TypeError: __call__() missing 3 required positional arguments: 'scope', 'receive', and 'send'

is what happens when you try to call the FastAPI app instance (i.e. app()) which is what the generated executable does.