Flask- Heroku 应用程序错误 - 没有 Web 进程正在运行

Question

I was trying to deploy a flask application online on heroku, The App is utilising SocketIO and Vanilla JS to handle the messages. I excepted it to run absolutely fine, It went smoothly and everything was installed but at the end, A Application Error Came Up saying-

"Application error - An error occurred in the application and your page could not be served. If you are the application owner, check your logs for details. You can do this from the Heroku CLI with the command heroku logs --tail "

In my command prompt I had a look at heroku logs --tail And got these results, I don't understand much about networking and heroku so please be light with my question.

D:\Aryan\Programming\Flask\Chat App SocketIO>heroku logs --tail
2021-02-11T08:45:34.666077+00:00 app[api]: Initial release by user umasaryan@gmail.com
2021-02-11T08:45:34.666077+00:00 app[api]: Release v1 created by user umasaryan@gmail.com
2021-02-11T08:45:34.991030+00:00 app[api]: Enable Logplex by user umasaryan@gmail.com
2021-02-11T08:45:34.991030+00:00 app[api]: Release v2 created by user umasaryan@gmail.com
2021-02-11T08:46:05.544056+00:00 heroku[router]: at=info code=H81 desc="Blank app" method=GET path="/" host=fathomless-ridge-52370.herokuapp.com request_id=36071200-cbca-4ad7-b220-3f73cf436ab1 fwd="103.208.71.79" dyno= connect= service= status=502 bytes= protocol=https
2021-02-11T08:46:05.935453+00:00 heroku[router]: at=info code=H81 desc="Blank app" method=GET path="/favicon.ico" host=fathomless-ridge-52370.herokuapp.com request_id=ba898a18-92e8-4271-96c9-786d8abc9f39 fwd="103.208.71.79" dyno= connect= service= status=502 bytes= protocol=https
2021-02-11T08:49:02.160398+00:00 heroku[router]: at=info code=H81 desc="Blank app" method=GET path="/" host=openbrainstorm.herokuapp.com request_id=f1c07f1b-99f9-4955-8464-060b33a38cf2 fwd="103.208.71.79" dyno= connect= service= status=502 bytes= protocol=https
2021-02-11T08:49:59.000000+00:00 app[api]: Build started by user umasaryan@gmail.com
2021-02-11T08:50:23.887409+00:00 app[api]: Deploy 7910bc2e by user umasaryan@gmail.com
2021-02-11T08:50:23.887409+00:00 app[api]: Release v3 created by user umasaryan@gmail.com
2021-02-11T08:50:32.000000+00:00 app[api]: Build succeeded
2021-02-11T08:51:06.781160+00:00 heroku[router]: at=error code=H14 desc="No web processes running" method=GET path="/" host=openbrainstorm.herokuapp.com request_id=aa5747b5-6d22-41a4-bb54-e63607e80712 fwd="103.208.71.79" dyno= connect= service= status=503 bytes= protocol=https

I tried to fix this error by adding the Procfile that looks like this-

web: gunicorn app:app --preload

This is what my directory structure looks like- Directory Structure Here

But still my issue was not resolved.

Any more debugging details on this question are welcome
My Git Repo- https://github.com/ahmishra/Flask-ChatApp

Answer 1

The first thing to do is to place the Procfile in the directory, where you initialized your git repository(where your requirements.txt is placed) or else Heroku will not be able to find it. Also you have not specified gunicorn in your requirements.txt so you also need to do that. Finally, I would like to say that you may run into error(gunicorn issue) if you have same name of your folder and file(app and app.py). So, you can rename app.py to appp.py and write this in the Procfile--

web: gunicorn appp:app

Which means that gunicorn will try to find app module in appp.py.