Monitoring labels aren't applied to rook-ceph-exporter

[abh]

Is this a bug report or feature request?

• Bug Report

Deviation from expected behavior:

The monitoring labels aren't applied to the rook-ceph-exporter service monitor.

Expected behavior:

The rook-ceph-exporter would have the same labels applied as the rook-ceph-mgr service monitor.

How to reproduce it (minimal and precise):

Add this to the cluster spec:

  labels:
    monitoring:
      prometheus: abc

and notice the label only being applied to two of the three service monitors.

[rspier]

Poking at the code today to see if I could fix this, looks like it's already possible.

spec:
  ... 
  labels:
    exporter:
      prometheus: perl

These labels are applied to both the rook-ceph-exporter Deployments and the ServiceMonitor.

rook/pkg/operator/ceph/cluster/nodedaemon/exporter.go

Lines 264 to 265 in 6ce7b1f

	if cephExporterLabels, ok := cephCluster.Spec.Labels["exporter"]; ok {
	if managedBy, ok := cephExporterLabels["rook.io/managedBy"]; ok {

We could also apply the monitoring labels, but not sure it's worth it.

[rkachach]

@abh @rspier is there something else we can do here? as @rspier commented labels can already be specified in the spec file.

[rspier]

At a minimum, maybe an exporter: example could be added to the docs? (I can send a PR if you agree.)

https://rook.io/docs/rook/latest-release/Storage-Configuration/Monitoring/ceph-monitoring/?h=monitoring#using-custom-label-selectors-in-prometheus

I think our expectation was that the monitoring: stanza would also apply to the exporter.

(If there's ever an non-backwards compatible change to the CephCluster object, it might be interesting to move the monitoring labels into the spec.monitoring stanza or even embed a ServiceMonitorSpec there for override purposes. But the existing system works.)

[abh]

nice, thanks @rkachach & @travisn!

[rspier]

+1!