Support Alerting on Group-Level Prometheus

Problem to solve

In https://gitlab.com/gitlab-org/gitlab-ce/issues/51963, we are adding support for Prometheus at the group-level and NOT including support for alerts. Here we implement support for alerts from group-level prometheus clusters.

Intended users

Further details

Proposal

With the alerting feature, sharing a Prometheus server between projects has gotten more complex.

  1. We dynamically build the Prometheus configuration, based on the configured alerts.
  2. There is also a webhook setup on the GitLab side, to receive any notifications of triggered alerts. I think this is at the project level.

So in order to support Prometheus at group level, we will need to:

  1. Aggregate the needed alerts that need to be configured across all the group's projects.
  2. Potentially configure each alert to notify the existing project webhook, or define a new group webhook endpoint.

Permissions and Security

Documentation

Testing

What does success look like, and how can we measure that?

Links / references