We have a Kotlin (JVM) application hosted in an Azure app. instance.
The app. talks to the Intuit Quickbooks API to obtain customer balances and to post invoices and payment receipts. It starts by obtaining a token via Quickbook's OAuth2 implementation.
Since 1 November 2024, we observe that when the app. makes a request, the request either times out or returns a 500 Gateway Error. Restarting the app. in the Azure web UI fixes the problem; the app. then communicates normally with the API ... for about 45 minutes. Then it reverts to the previous behaviour, where requests either time out or receive 500 Gateway Error.
The same app. runs correctly and as expected in our local office environment, at all times.
We don't think it's a general failure of the Quickbooks API because the local office instance will connect to the API even when the Azure instance will not.
[Later] In an attempt to diagnose the problem, I set our app. to re-authenticate with the API every 45 minutes, which means a POST request and it alternately succeeds and times out; mostly — sometimes it times out two to four times before succeeding again.
What might cause this behaviour?
