[FIXED] Python flask server on Heroku

Issue

i have a python (flask) server, it works locally, but i want to deploy my flask server (socketio) on Heroku, so basically the final situation is:

1. Flask server (socketio on Heroku)
2. Client js on host like (000webhost)

but when i deploy server it does not work

socketio = SocketIO(app, cors_allowed_origins='*')
porta = int(os.environ.get('PORT', 5000))
if __name__ == '__main__':
socketio.run(app, port=porta)

Procfile:

web: python3 server.py

Solution

You need to bind to '0.0.0.0' instead of the default ('localhost'). This allows the socketio server to accept external connections.

socketio.run(host='0.0.0.0', port=porta)

You can see an example of this in a Heroku blog post about Django, another Python web framework: https://blog.heroku.com/python_and_django

Answered By - Zam Abdul Vahid