[server] add a metric for received webhook events

[AlexTugarev]

Problem to solve

Let's see the frequency of webhook events. Tough it's clear, that we want/need to decouple inrush from actually handling of those events, it would be interesting to see the impact on the current system.

[jldec]

Some overlap with #10341
Would like to be able to observe webhooks for specific repos (for debugging prebuilds).

[AlexTugarev]

@jldec, you are right about the overlap. Do you think merging both is necessary?

I'd like to see a metric for received webhook events per provider in order to identify spikes (or issues) and correlate with load induced.

[jldec]

Feel free to combine the 2 issues. The requirement from a support perspective is that we need to be able to trace working prebuilds from repo commit -> webhook trigger -> prebuild start -> prebuild end.

This would give us a baseline to find issues when say webhooks stop arriving from the git provider, or prebuilds are not starting because of auth for a specific user, or because of a broken git integration.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.