I currently have my flask application running inside a docker container. In my Dockerfile I have a command which will run python manage.py runserver to run the app.

However I want to deploy the application to Heroku and run the app with the gunicorn server. I've prepared a basic Procfile which looks like:

web: gunicorn manage:app

When I deploy to Heroku I get the following errors:

2016-12-16T00:27:00.905884 00:00 app[api]: Release v91 created by user
2016-12-16T00:27:00.905884 00:00 app[api]: Deployed web (e5d8c5313a04) by user
2016-12-16T00:27:01.904778 00:00 heroku[web.1]: State changed from crashed to starting
2016-12-16T00:27:13.752569 00:00 heroku[web.1]: Starting process with command `python3`
2016-12-16T00:27:15.768266 00:00 heroku[web.1]: State changed from starting to crashed
2016-12-16T00:27:15.740802 00:00 heroku[web.1]: Process exited with status 0
2016-12-16T00:27:17.024469 00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=myapp.herokuapp.com request_id=e286fb83-7012-49be-a553-625e8d056115 fwd="82.37.9.108" dyno= connect= service= status=503 bytes=