feat: Manage prometheus resources

[tolusha]

What does this PR do?

1. New metrics package (pkg/deploy/metrics/) — a new reconciler that manages Prometheus resources:
   • ServiceMonitor objects for both Che Server (che-host) and DWO (devworkspace-controller)
   • RBAC (Role + RoleBinding) granting the prometheus-k8s service account access to scrape metrics endpoints
   • Adds the openshift.io/cluster-monitoring: "true" label to the operator namespace so OpenShift's built-in monitoring stack discovers the ServiceMonitors

Screenshot/screencast of this PR

N/A

What issues does this PR fix or reference?

https://redhat.atlassian.net/browse/CRW-8629
https://redhat.atlassian.net/browse/CRW-8589
https://redhat.atlassian.net/browse/CRW-8315

How to test this PR?

1. Deploy Eclipse Che, start a workspace
2. Ensure that me collect devworkspace and che-server specific metrics without creating any additional resources
   https://eclipse.dev/che/docs/stable/administration-guide/monitoring-che/
   https://eclipse.dev/che/docs/stable/administration-guide/monitoring-the-dev-workspace-operator/

Common Test Scenarios

• Deploy Eclipse Che
• Start an empty workspace
• Open terminal and build/run an image
• Stop a workspace
• Check operator logs for reconciliation errors or infinite reconciliation loops

PR Checklist

As the author of this Pull Request I made sure that:

• The Eclipse Contributor Agreement is valid
• Code produced is complete
• Code builds without errors
• Tests are covering the bugfix
• The repository devfile is up to date and works
• Relevant user documentation updated
• Relevant contributing documentation updated
• CI/CD changes implemented, documented and communicated

Reviewers

Reviewers, please comment how you tested the PR when approving it.

[openshift-ci]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[tolusha]

/retest

[rohanKanojia]

Sorry, I might not have the full context. Why is pods needed?

[tolusha]

I not 100% sure, probably some requirements
https://eclipse.dev/che/docs/stable/administration-guide/monitoring-che/

[tolusha]

Hi! I'm che-ai-assistant — I help with your pull requests.

Available commands:

• /che-ai-assistant generate-che-doc — Generate a documentation PR based on this PR's changes
• /che-ai-assistant ok-pr-review — Run a comprehensive PR review (summary, code review, deep review, impact analysis)
• /che-ai-assistant help — Show this help message

[rohanKanojia]

While testing it I observe that ServiceMonitor for devworkspace gets created but che-host is not getting created.

On installing Eclipse Che based on these changes and creating a DevWorkspace.

1. ServiceMonitor got created:

kubectl get servicemonitor -neclipse-che                                                                                                                                            
NAME           AGE
devworkspace   106s

2. Role/RoleBinding got created:

kubectl get role -neclipse-che | grep prometheus
devworkspace-prometheus                                           2026-05-14T15:39:05Z

kubectl get rolebinding -neclipse-che | grep prometheus
devworkspace-prometheus                                           Role/devworkspace-prometheus                                           2m17s

These get garbage collected when CheCluster gets deleted, confirming ownerReference is working correctly.

How to enable Che equivalent resources? I can confirm metrics is enabled in CheCluster CR:

oc get checluster -o yaml | grep -A2  metrics                                                                                                                          
      metrics:
        enable: true
      pluginRegistry:

[tolusha]

@rohanKanojia
Thank you for noticing that. It has been fixed.

While testing it I observe that ServiceMonitor for devworkspace gets created but che-host is not getting created.
fixed

[tolusha]

/che-ai-assistant generate-che-doc

Created documentation PR: eclipse-che/che-docs#3106

[tolusha]

/che-ai-assistant ok-pr-review

[tolusha]

Review Summary

This PR adds a well-designed metrics reconciler with clean abstractions and good test coverage. The PrometheusResourceProvider interface pattern is well-motivated, and the interval preservation mechanism shows operational awareness.

Key findings:

• 7 inline comments with specific suggestions
• Most are minor improvements (documentation, test coverage, deprecated package usage)
• No blocking issues found

The reconciler design is solid and follows established patterns in the codebase. Great work on the upgrade path with deleteAbandonedResources and graceful degradation for clusters without Prometheus Operator.

[tolusha]

Package-level isAbandonedResourcesDeleted isn't reset between tests. TestReconcileMetrics sets it true, so later tests skip deletion code. Consider a reset function in init_test.go or make this per-DeployContext.

[rohanKanojia]

I tested it again and now I can confirm both ServiceMonitors are available:

$ kubectl get servicemonitor -neclipse-che                                                                                                                              
NAME           AGE
che            24s
devworkspace   25s
$ kubectl get role -neclipse-che | grep prometheus                                                                                                                       
che-prometheus                                                    2026-05-18T10:31:23Z
devworkspace-prometheus                                           2026-05-18T10:31:23Z

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: rohanKanojia, tolusha

The full list of commands accepted by this bot can be found here.

Details

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment