[DO NOT MERGE] UPSTREAM: <carry>: fix kube_persistentvolume_plugin_type_counts

[dfajmon]

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Summary by CodeRabbit

• New Features

  • Enhanced persistent volume metrics collection with explicit tracking of metric-capable volume plugins.
  • Added support for metrics for local volume plugins.

• Tests

  • New unit tests validating volume plugin name reporting for persistent volume metrics.

[openshift-ci]

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[openshift-ci-robot]

@dfajmon: the contents of this pull request could not be automatically validated.

The following commits could not be validated and must be approved by a top-level approver:

• 5c2d4b1|UPSTREAM: : fix kube_persistentvolume_plugin_type_counts missing plugin_name: does not specify an upstream backport in the commit message

Comment /validate-backports to re-evaluate validity of the upstream PRs, for example when they are merged upstream.

[openshift-ci]

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[coderabbitai]

Walkthrough

Persistent volume controller adds a separate metrics plugin manager, initialized from metrics-specific volume plugins probed during setup. Local volume plugin is registered. Metrics plugins are probed and wired into controller initialization, allowing metrics collection to use different plugins than volume provisioning.

Changes

Metrics Plugin Manager Integration

Layer / File(s)	Summary
Controller-manager plugin probing and local plugin link cmd/kube-controller-manager/app/plugins.go	Import k8s.io/kubernetes/pkg/volume/local and append local.ProbeVolumePlugins() results to the controller-manager's probed plugin set.
Metrics plugin probing in controller construction cmd/kube-controller-manager/app/core.go	newPersistentVolumeBinderController calls ProbePersistentVolumePlugins and assigns the result to ControllerParameters.MetricsVolumePlugins, returning an error if probing fails.
Metrics plugin manager and controller wiring pkg/controller/volume/persistentvolume/pv_controller_base.go, pkg/controller/volume/persistentvolume/pv_controller.go	ControllerParameters gains MetricsVolumePlugins; PersistentVolumeController gains metricsPluginMgr. NewController initializes metricsPluginMgr from p.MetricsVolumePlugins and metrics registration uses &ctrl.metricsPluginMgr.
Plugin name resolution test pkg/controller/volume/persistentvolume/metrics/metrics_test.go	Adds TestGetPVPluginName to verify getPVPluginName returns kubernetes.io/csi:<driver> when CSI plugins are registered and pluginNameNotAvailable when absent.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 11 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (11 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Stable And Deterministic Test Names	✅ Passed	Test file metrics_test.go has stable, deterministic test names with no dynamic values, generated identifiers, timestamps, or other unstable elements that could change between runs.
Test Structure And Quality	✅ Passed	PR adds only standard Go tests, not Ginkgo tests. The custom check explicitly reviews "Ginkgo test code," making it inapplicable to this PR.
Microshift Test Compatibility	✅ Passed	PR adds only a standard Go unit test (TestGetPVPluginName), not Ginkgo e2e tests. MicroShift compatibility check only applies to Ginkgo e2e tests.
Single Node Openshift (Sno) Test Compatibility	✅ Passed	No Ginkgo e2e tests are added in this PR. The only test file added is metrics_test.go with TestGetPVPluginName, which is a standard Go unit test (not a Ginkgo test). The check is not applicable.
Topology-Aware Scheduling Compatibility	✅ Passed	PR modifies only internal Go controller code for metrics collection. No deployment manifests, scheduling constraints, or topology-related configurations were added or modified.
Ote Binary Stdout Contract	✅ Passed	PR modifies kube-controller-manager (production code), not OTE binaries. OTE Binary Stdout Contract applies only to openshift-tests extension binaries, not system components.
Ipv6 And Disconnected Network Test Compatibility	✅ Passed	No Ginkgo e2e tests were added in this PR. The only new test is a standard Go unit test (TestGetPVPluginName) that does not use Ginkgo patterns or test e2e functionality.
Title check	✅ Passed	The title clearly references the specific fix being implemented (kube_persistentvolume_plugin_type_counts) and identifies it as an upstream carry patch, directly relating to the core changes across multiple files that add metrics plugin support.

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@cmd/kube-controller-manager/app/core.go`:
- Around line 334-336: The error return in newPersistentVolumeBinderController
incorrectly returns three values; change the error path in the metrics volume
plugin probe to return only (nil, error) by removing the extraneous boolean and
wrap the original probe error using fmt.Errorf("failed to probe metrics volume
plugins when starting persistentvolume controller: %w", err) so the function
signature (Controller, error) is respected and the underlying error is
preserved.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

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Run ID: 55e2cc95-d7d6-404c-bb43-74e4598e3128

📥 Commits

Reviewing files that changed from the base of the PR and between 99b75aa and 5c2d4b1.

📒 Files selected for processing (5)

• cmd/kube-controller-manager/app/core.go
• cmd/kube-controller-manager/app/plugins.go
• pkg/controller/volume/persistentvolume/metrics/metrics_test.go
• pkg/controller/volume/persistentvolume/pv_controller.go
• pkg/controller/volume/persistentvolume/pv_controller_base.go

[openshift-ci-robot]

@dfajmon: the contents of this pull request could not be automatically validated.

The following commits could not be validated and must be approved by a top-level approver:

• dd4a857|UPSTREAM: : fix kube_persistentvolume_plugin_type_counts missing plugin_name: does not specify an upstream backport in the commit message

Comment /validate-backports to re-evaluate validity of the upstream PRs, for example when they are merged upstream.

[openshift-ci]

@dfajmon: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/unit	dd4a857	link	true	/test unit
ci/prow/e2e-aws-ovn-runc	dd4a857	link	false	/test e2e-aws-ovn-runc
ci/prow/e2e-aws-ovn-techpreview	dd4a857	link	false	/test e2e-aws-ovn-techpreview
ci/prow/verify	dd4a857	link	true	/test verify

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