Hello world for PlotlyExpress, Dash and Heroku

I am trying to make a simple Dash Hello World app on Heroku with a simple PlotlyExpress chart. Unfortunately I have some problems and wonder if someone could help me? The code is forked from GitHub - plotly/dash-px: Simple Dash app using Plotly Express and when I deploy the app I get the following errors:

2019-08-08T14:48:11.064514+00:00 heroku[router]: at=error code=H14 desc=“No web processes running” method=GET path=“/” host=dash-px.herokuapp.com request_id=c8cd2019-9705-400c-b4a2-606261dc8a78 fwd=“188.65.152.146” dyno= connect= service= status=503 bytes= protocol=https

2019-08-08T14:48:11.206249+00:00 heroku[router]: at=error code=H14 desc=“No web processes running” method=GET path=“/favicon.ico” host=dash-px.herokuapp.com request_id=f6135233-1abd-49c7-9331-29a8ea8f7082 fwd=“188.65.152.146” dyno= connect= service= status=503 bytes= protocol=https

I would also like to update the code to the latest version of Plotly and Dash.

Have you written a Procfile? Looks like you might need to define the web process, see here too. You may also need to explicitly start a web process with something like heroku ps:scale web=1, but it should do that for you automatically.

1 Like

Thanks, I have tried that containing:
web: gunicorn app:server and also added gunicorn==19.7.1 to requirements.txt but I get the following error:
2019-08-09T06:25:40.329974+00:00 app[web.1]: OSError: [Errno 98] Address already in use

    2019-08-09T06:25:40.331818+00:00 app[web.1]: [2019-08-09 06:25:40 +0000] [12] [INFO] Worker exiting (pid: 12)

    2019-08-09T06:25:40.787124+00:00 heroku[web.1]: State changed from up to crashed

    2019-08-09T06:25:40.494291+00:00 app[web.1]: [2019-08-09 06:25:40 +0000] [10] [INFO] Worker exiting (pid: 10)

    2019-08-09T06:25:40.688203+00:00 app[web.1]: [2019-08-09 06:25:40 +0000] [4] [INFO] Shutting down: Master

    2019-08-09T06:25:40.688282+00:00 app[web.1]: [2019-08-09 06:25:40 +0000] [4] [INFO] Reason: Worker failed to boot.

    2019-08-09T06:25:40.763990+00:00 heroku[web.1]: Process exited with status 3

    2019-08-09T06:25:44.000000+00:00 app[api]: Build succeeded

    2019-08-09T06:26:05.033727+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=dash-px.herokuapp.com request_id=0a4da830-90a8-480e-a03a-262739fcdf97 fwd="188.65.152.146" dyno= connect= service= status=503 bytes= protocol=https

    2019-08-09T06:26:05.170222+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=dash-px.herokuapp.com request_id=4e454e37-1880-4664-ae5f-5f9c68047a40 fwd="188.65.152.146" dyno= connect= service= status=503 bytes= protocol=https

/Max

I solved the problems by adding some code and also adding flask (I forgot about that). Now I will try to update the code to the latest versions. You can find the code at https://github.com/maxtillberg/dash-px

/Max