Merge pull request #59646 from mlmhl/fix_volume_metrics_e2e

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Add bound/unbound pv/pvc volume metrics

**What this PR does / why we need it**:

Fix two bugs in bound/unbound pv/pvc volumes metric e2e test:

1. Check `HasRegisteredMaster` in `BeforeEach` instead of each tests because we will grab the metrics in `BeforeEach`

2. Fix `calculateRelativeValues` bug, if there are other PV/PVC exist in the cluster, `calculateRelativeValues` will return a map like `map[string]int64{"some-storage-class-name": 0}`, this will lead to test failure. We should skip these unchanged numbers.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #59517

**Release note**:

```release-note
NONE
```

/sig storage

pkg/controller/volume/persistentvolume/BUILD

@@ -24,6 +24,7 @@ go_library(
         "//pkg/cloudprovider:go_default_library",
         "//pkg/controller:go_default_library",
         "//pkg/controller/volume/events:go_default_library",
+        "//pkg/controller/volume/persistentvolume/metrics:go_default_library",
         "//pkg/features:go_default_library",
         "//pkg/util/goroutinemap:go_default_library",
         "//pkg/util/goroutinemap/exponentialbackoff:go_default_library",
@@ -117,6 +118,7 @@ filegroup(
     name = "all-srcs",
     srcs = [
         ":package-srcs",
+        "//pkg/controller/volume/persistentvolume/metrics:all-srcs",
         "//pkg/controller/volume/persistentvolume/options:all-srcs",
     ],
     tags = ["automanaged"],

pkg/controller/volume/persistentvolume/metrics/BUILD

@@ -0,0 +1,30 @@
+package(default_visibility = ["//visibility:public"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["metrics.go"],
+    importpath = "k8s.io/kubernetes/pkg/controller/volume/persistentvolume/metrics",
+    deps = [
+        "//vendor/github.com/golang/glog:go_default_library",
+        "//vendor/github.com/prometheus/client_golang/prometheus:go_default_library",
+        "//vendor/k8s.io/api/core/v1:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)

pkg/controller/volume/persistentvolume/metrics/metrics.go

@@ -0,0 +1,184 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package metrics
+
+import (
+	"sync"
+
+	"k8s.io/api/core/v1"
+
+	"github.com/golang/glog"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	// Subsystem names.
+	pvControllerSubsystem = "pv_collector"
+
+	// Metric names.
+	boundPVKey    = "bound_pv_count"
+	unboundPVKey  = "unbound_pv_count"
+	boundPVCKey   = "bound_pvc_count"
+	unboundPVCKey = "unbound_pvc_count"
+
+	// Label names.
+	namespaceLabel    = "namespace"
+	storageClassLabel = "storage_class"
+)
+
+var registerMetrics sync.Once
+
+// PVLister used to list persistent volumes.
+type PVLister interface {
+	List() []interface{}
+}
+
+// PVCLister used to list persistent volume claims.
+type PVCLister interface {
+	List() []interface{}
+}
+
+// Register all metrics for pv controller.
+func Register(pvLister PVLister, pvcLister PVCLister) {
+	registerMetrics.Do(func() {
+		prometheus.MustRegister(newPVAndPVCCountCollector(pvLister, pvcLister))
+	})
+}
+
+func newPVAndPVCCountCollector(pvLister PVLister, pvcLister PVCLister) *pvAndPVCCountCollector {
+	return &pvAndPVCCountCollector{pvLister, pvcLister}
+}
+
+// Custom collector for current pod and container counts.
+type pvAndPVCCountCollector struct {
+	// Cache for accessing information about PersistentVolumes.
+	pvLister PVLister
+	// Cache for accessing information about PersistentVolumeClaims.
+	pvcLister PVCLister
+}
+
+var (
+	boundPVCountDesc = prometheus.NewDesc(
+		prometheus.BuildFQName("", pvControllerSubsystem, boundPVKey),
+		"Gauge measuring number of persistent volume currently bound",
+		[]string{storageClassLabel}, nil)
+	unboundPVCountDesc = prometheus.NewDesc(
+		prometheus.BuildFQName("", pvControllerSubsystem, unboundPVKey),
+		"Gauge measuring number of persistent volume currently unbound",
+		[]string{storageClassLabel}, nil)
+
+	boundPVCCountDesc = prometheus.NewDesc(
+		prometheus.BuildFQName("", pvControllerSubsystem, boundPVCKey),
+		"Gauge measuring number of persistent volume claim currently bound",
+		[]string{namespaceLabel}, nil)
+	unboundPVCCountDesc = prometheus.NewDesc(
+		prometheus.BuildFQName("", pvControllerSubsystem, unboundPVCKey),
+		"Gauge measuring number of persistent volume claim currently unbound",
+		[]string{namespaceLabel}, nil)
+)
+
+func (collector *pvAndPVCCountCollector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- boundPVCountDesc
+	ch <- unboundPVCountDesc
+	ch <- boundPVCCountDesc
+	ch <- unboundPVCCountDesc
+}
+
+func (collector *pvAndPVCCountCollector) Collect(ch chan<- prometheus.Metric) {
+	collector.pvCollect(ch)
+	collector.pvcCollect(ch)
+}
+
+func (collector *pvAndPVCCountCollector) pvCollect(ch chan<- prometheus.Metric) {
+	boundNumberByStorageClass := make(map[string]int)
+	unboundNumberByStorageClass := make(map[string]int)
+	for _, pvObj := range collector.pvLister.List() {
+		pv, ok := pvObj.(*v1.PersistentVolume)
+		if !ok {
+			continue
+		}
+		if pv.Status.Phase == v1.VolumeBound {
+			boundNumberByStorageClass[pv.Spec.StorageClassName]++
+		} else {
+			unboundNumberByStorageClass[pv.Spec.StorageClassName]++
+		}
+	}
+	for storageClassName, number := range boundNumberByStorageClass {
+		metric, err := prometheus.NewConstMetric(
+			boundPVCountDesc,
+			prometheus.GaugeValue,
+			float64(number),
+			storageClassName)
+		if err != nil {
+			glog.Warningf("Create bound pv number metric failed: %v", err)
+			continue
+		}
+		ch <- metric
+	}
+	for storageClassName, number := range unboundNumberByStorageClass {
+		metric, err := prometheus.NewConstMetric(
+			unboundPVCountDesc,
+			prometheus.GaugeValue,
+			float64(number),
+			storageClassName)
+		if err != nil {
+			glog.Warningf("Create unbound pv number metric failed: %v", err)
+			continue
+		}
+		ch <- metric
+	}
+}
+
+func (collector *pvAndPVCCountCollector) pvcCollect(ch chan<- prometheus.Metric) {
+	boundNumberByNamespace := make(map[string]int)
+	unboundNumberByNamespace := make(map[string]int)
+	for _, pvcObj := range collector.pvcLister.List() {
+		pvc, ok := pvcObj.(*v1.PersistentVolumeClaim)
+		if !ok {
+			continue
+		}
+		if pvc.Status.Phase == v1.ClaimBound {
+			boundNumberByNamespace[pvc.Namespace]++
+		} else {
+			unboundNumberByNamespace[pvc.Namespace]++
+		}
+	}
+	for namespace, number := range boundNumberByNamespace {
+		metric, err := prometheus.NewConstMetric(
+			boundPVCCountDesc,
+			prometheus.GaugeValue,
+			float64(number),
+			namespace)
+		if err != nil {
+			glog.Warningf("Create bound pvc number metric failed: %v", err)
+			continue
+		}
+		ch <- metric
+	}
+	for namespace, number := range unboundNumberByNamespace {
+		metric, err := prometheus.NewConstMetric(
+			unboundPVCCountDesc,
+			prometheus.GaugeValue,
+			float64(number),
+			namespace)
+		if err != nil {
+			glog.Warningf("Create unbound pvc number metric failed: %v", err)
+			continue
+		}
+		ch <- metric
+	}
+}

pkg/controller/volume/persistentvolume/pv_controller_base.go

@@ -40,6 +40,7 @@ import (
 	"k8s.io/client-go/util/workqueue"
 	"k8s.io/kubernetes/pkg/cloudprovider"
 	"k8s.io/kubernetes/pkg/controller"
+	"k8s.io/kubernetes/pkg/controller/volume/persistentvolume/metrics"
 	"k8s.io/kubernetes/pkg/util/goroutinemap"
 	vol "k8s.io/kubernetes/pkg/volume"
 
@@ -277,6 +278,8 @@ func (ctrl *PersistentVolumeController) Run(stopCh <-chan struct{}) {
 	go wait.Until(ctrl.volumeWorker, time.Second, stopCh)
 	go wait.Until(ctrl.claimWorker, time.Second, stopCh)
 
+	metrics.Register(ctrl.volumes.store, ctrl.claims)
+
 	<-stopCh
 }