Intermittent HTTP 404 when trying to edit variables through web UI.

[jenskeiner]

Hi all,

I'm not entirely sure I should file this as a bug yet, but I'm regularly seeing HTTP 404 return codes from the web server when trying to edit variables. Maybe somebody has seen similar behaviour and would have pointers on how to investigate.

Any help highly appreciated. Details below.

The Airflow instance in question runs in a Kubernetes cluster (Docker image apache/airflow:1.10.12-python3.8) with the usual two pods for the scheduler and the web server part. The database (PostgreSQL) is external to the cluster and sits on a dedicated host.

Quite often, when trying to edit a variable through the web UI, I get an HTTP 404 return code back. This happens both when clicking on the edit button in the first place, as well as when clicking on the save button to persist the changes. In a minority of cases, the editing process actually works as expected.

I've already enabled debug logging as well as switched the web server to a different worker class (from sync to tornado), unfortunately to no avail. I'm able to see the 404 error pop up in the web server's error log, but I'm still unable to see what's actually causing it.

I assume that the backing Python code may have trouble accessing the variable for some reason, but haven't been able to confirm so far. Is there a way to enable more detailed logging in the Python back end so this can be traced further?

Best,

Jens