Heroku app runs locally but gets H12 timeout error (uses a package)

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Chapters
00:00 Heroku App Runs Locally But Gets H12 Timeout Error (Uses A Package)
01:52 Accepted Answer Score 14
02:23 Thank you

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Full question
https://stackoverflow.com/questions/1602...

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Tags
#python #heroku #flask #gunicorn

#avk47

ACCEPTED ANSWER

Score 14

The issue is that run.py unguardedly calls app.run - this actually calls werkzeug.serving.run_simple which starts a sub-process to handle incoming requests ... which you don't want to do when running under gunicorn (since gunicorn will handle the process management for you).

Simply add an if __name__ == "__main__" guard before your app.run call and everything should work:

# run.py
if __name__ == "__main__":
    app.run()