What redirect_uri should be used with heroku?

[LiamRun]

I have a personal app set up to pull my fitbit data and put it into a google sheet.

This works on local but I want to set it up on heroku so that I can access it by going to a url rather than running on one specific machine.

I'm currently using the redirect_uri: http://127.0.0.1:8080/ 

But this does not work on Heroku. My application times out with 

2020-10-24T15:58:17.948773+00:00 heroku[router]: at=error code=H12 desc="Request timeout" method=GET path="/FitbitLiam/" host=EXAMPLE.herokuapp.com request_id=4a61ca6f-8507-47a3-80c3-7e5961dca467 fwd="79.70.227.136" dyno=web.1 connect=1ms service=30000ms status=503 bytes=0 protocol=https

I am assuming it's because I shouldn't be using a local url.

Any help would be appreciated!!

[JohnFitbit]

Hi @LiamRun,

I'm not familiar with the Heroku platform but did ask around for you.

Since Heroku is a cloud platform, redirecting to localhost may fail because it’s not going back to your application. You may need to change the callback URL to something on the Heroku platform.  We're unsure of how Heroku is setup, but the assumption is that you would need a URL like https://herokuapp.com/callbackURL instead of references to these “path=“/FitbitLiam/” host=EXAMPLE.herokuapp.com

I hope this helps. Let me know if you have any additional questions.