ServiceBus Topic Trigger requires Manage rights to work properly

[mathewc]

Our scale controller relies on the ServiceBus GetSubscription API to access the MessageCount for a subscription to determine whether it should scale out. That API requires Manage rights. So while the Function runtime supports Listen rights, users will see unexpected behavior unless they give us a Manage rights connection string (until this issue is fixed).

[paulbatum]

Can we find some way to get the message count without manage rights. The answer is probably no, but its worth doing some more investigation as this would be the simplest fix.

Assuming no for the above, have the functions runtime emit a warning to host logs indicating that it needs a manage level connection string. Only do so when running in dynamic.

During investigation, use the ScaleControllerEvents table to verify you are reproing the issue correctly.

[paulbatum]

@mamaso So we went with the emit host logs approach right? I see thats merged, can we close this?

[mamaso]

@mathewc and I chatted and decided to revert the logging part of the PR, we felt it wasn't worth the added complexity when the real part of the problem is in the scale controller and the host logs are not visible enough.

Keep this open for:

1. the scale controller work
2. the work to route BindingProvider traces to function logs (maybe)

[lindydonna]

FYI to @mathewc @davidebbo: we had three support cases in Jan/Feb that matched this symptom.

Customers report that their functions seem to only work properly when opened in the portal. I'm assuming it's because the Scale Controller doesn't have the right permissions.

I'm adding the reliability label and removing the milestone so we re-triage.

[christopheranderson]

@tohling - could you please provide status on this?