* Alerting: Send alerts to external Alertmanager(s) Within this PR we're adding support for registering or unregistering sending to a set of external alertmanagers. A few of the things that are going are: - Introduce a new table to hold "admin" (either org or global) configuration we can change at runtime. - A new periodic check that polls for this configuration and adjusts the "senders" accordingly. - Introduces a new concept of "senders" that are responsible for shipping the alerts to the external Alertmanager(s). In a nutshell, this is the Prometheus notifier (the one in charge of sending the alert) mapped to a multi-tenant map. There are a few code movements here and there but those are minor, I tried to keep things intact as much as possible so that we could have an easier diff.
What
This aims to define the unified alerting API as code. It generates OpenAPI definitions from go structs
Running
make openapi