Merge pull request #112907 from logicalhan/stable-metric-metric

add meta-metrics for metrics framework

staging/src/k8s.io/component-base/metrics/counter.go

@@ -44,7 +44,7 @@ func NewCounter(opts *CounterOpts) *Counter {
 
 	kc := &Counter{
 		CounterOpts: opts,
-		lazyMetric:  lazyMetric{},
+		lazyMetric:  lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	kc.setPrometheusCounter(noop)
 	kc.lazyInit(kc, BuildFQName(opts.Namespace, opts.Subsystem, opts.Name))
@@ -129,7 +129,7 @@ func NewCounterVec(opts *CounterOpts, labels []string) *CounterVec {
 		CounterVec:     noopCounterVec,
 		CounterOpts:    opts,
 		originalLabels: labels,
-		lazyMetric:     lazyMetric{},
+		lazyMetric:     lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	cv.lazyInit(cv, fqName)
 	return cv

staging/src/k8s.io/component-base/metrics/gauge.go

@@ -46,7 +46,7 @@ func NewGauge(opts *GaugeOpts) *Gauge {
 
 	kc := &Gauge{
 		GaugeOpts:  opts,
-		lazyMetric: lazyMetric{},
+		lazyMetric: lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	kc.setPrometheusGauge(noop)
 	kc.lazyInit(kc, BuildFQName(opts.Namespace, opts.Subsystem, opts.Name))
@@ -115,7 +115,7 @@ func NewGaugeVec(opts *GaugeOpts, labels []string) *GaugeVec {
 		GaugeVec:       noopGaugeVec,
 		GaugeOpts:      opts,
 		originalLabels: labels,
-		lazyMetric:     lazyMetric{},
+		lazyMetric:     lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	cv.lazyInit(cv, fqName)
 	return cv

staging/src/k8s.io/component-base/metrics/histogram.go

@@ -52,7 +52,7 @@ func NewHistogram(opts *HistogramOpts) *Histogram {
 
 	h := &Histogram{
 		HistogramOpts: opts,
-		lazyMetric:    lazyMetric{},
+		lazyMetric:    lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	h.setPrometheusHistogram(noopMetric{})
 	h.lazyInit(h, BuildFQName(opts.Namespace, opts.Subsystem, opts.Name))
@@ -119,7 +119,7 @@ func NewHistogramVec(opts *HistogramOpts, labels []string) *HistogramVec {
 		HistogramVec:   noopHistogramVec,
 		HistogramOpts:  opts,
 		originalLabels: labels,
-		lazyMetric:     lazyMetric{},
+		lazyMetric:     lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	v.lazyInit(v, fqName)
 	return v

staging/src/k8s.io/component-base/metrics/legacyregistry/registry.go

@@ -47,6 +47,7 @@ var (
 func init() {
 	RawMustRegister(collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}))
 	RawMustRegister(collectors.NewGoCollector(collectors.WithGoCollectorRuntimeMetrics(collectors.MetricsAll)))
+	defaultRegistry.RegisterMetaMetrics()
 }
 
 // Handler returns an HTTP handler for the DefaultGatherer. It is

staging/src/k8s.io/component-base/metrics/metric.go

@@ -72,6 +72,7 @@ type lazyMetric struct {
 	markDeprecationOnce sync.Once
 	createOnce          sync.Once
 	self                kubeCollector
+	stabilityLevel      StabilityLevel
 }
 
 func (r *lazyMetric) IsCreated() bool {
@@ -149,6 +150,7 @@ func (r *lazyMetric) Create(version *semver.Version) bool {
 	if r.IsHidden() {
 		return false
 	}
+
 	r.createOnce.Do(func() {
 		r.createLock.Lock()
 		defer r.createLock.Unlock()
@@ -159,6 +161,13 @@ func (r *lazyMetric) Create(version *semver.Version) bool {
 			r.self.initializeMetric()
 		}
 	})
+	sl := r.stabilityLevel
+	deprecatedV := r.self.DeprecatedVersion()
+	dv := ""
+	if deprecatedV != nil {
+		dv = deprecatedV.String()
+	}
+	registeredMetrics.WithLabelValues(string(sl), dv).Inc()
 	return r.IsCreated()
 }
 

staging/src/k8s.io/component-base/metrics/registry.go

@@ -36,6 +36,31 @@ var (
 	registries          []*kubeRegistry // stores all registries created by NewKubeRegistry()
 	registriesLock      sync.RWMutex
 	disabledMetrics     = map[string]struct{}{}
+
+	registeredMetrics = NewCounterVec(
+		&CounterOpts{
+			Name:           "registered_metric_total",
+			Help:           "The count of registered metrics broken by stability level and deprecation version.",
+			StabilityLevel: ALPHA,
+		},
+		[]string{"stability_level", "deprecated_version"},
+	)
+
+	disabledMetricsTotal = NewCounter(
+		&CounterOpts{
+			Name:           "disabled_metric_total",
+			Help:           "The count of disabled metrics.",
+			StabilityLevel: ALPHA,
+		},
+	)
+
+	hiddenMetricsTotal = NewCounter(
+		&CounterOpts{
+			Name:           "hidden_metric_total",
+			Help:           "The count of hidden metrics.",
+			StabilityLevel: ALPHA,
+		},
+	)
 )
 
 // shouldHide be used to check if a specific metric with deprecated version should be hidden
@@ -67,6 +92,7 @@ func SetDisabledMetric(name string) {
 	disabledMetricsLock.Lock()
 	defer disabledMetricsLock.Unlock()
 	disabledMetrics[name] = struct{}{}
+	disabledMetricsTotal.Inc()
 }
 
 // SetShowHidden will enable showing hidden metrics. This will no-opt
@@ -129,6 +155,8 @@ type KubeRegistry interface {
 	// Reset invokes the Reset() function on all items in the registry
 	// which are added as resettables.
 	Reset()
+	// RegisterMetaMetrics registers metrics about the number of registered metrics.
+	RegisterMetaMetrics()
 }
 
 // kubeRegistry is a wrapper around a prometheus registry-type object. Upon initialization
@@ -250,6 +278,7 @@ func (kr *kubeRegistry) trackHiddenCollector(c Registerable) {
 	defer kr.hiddenCollectorsLock.Unlock()
 
 	kr.hiddenCollectors[c.FQName()] = c
+	hiddenMetricsTotal.Inc()
 }
 
 // trackStableCollectors stores all custom collectors.
@@ -329,9 +358,14 @@ func newKubeRegistry(v apimachineryversion.Info) *kubeRegistry {
 	return r
 }
 
-// NewKubeRegistry creates a new vanilla Registry without any Collectors
-// pre-registered.
+// NewKubeRegistry creates a new vanilla Registry
 func NewKubeRegistry() KubeRegistry {
 	r := newKubeRegistry(BuildVersion())
 	return r
 }
+
+func (r *kubeRegistry) RegisterMetaMetrics() {
+	r.MustRegister(registeredMetrics)
+	r.MustRegister(disabledMetricsTotal)
+	r.MustRegister(hiddenMetricsTotal)
+}

staging/src/k8s.io/component-base/metrics/summary.go

@@ -49,7 +49,7 @@ func NewSummary(opts *SummaryOpts) *Summary {
 
 	s := &Summary{
 		SummaryOpts: opts,
-		lazyMetric:  lazyMetric{},
+		lazyMetric:  lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	s.setPrometheusSummary(noopMetric{})
 	s.lazyInit(s, BuildFQName(opts.Namespace, opts.Subsystem, opts.Name))
@@ -118,7 +118,7 @@ func NewSummaryVec(opts *SummaryOpts, labels []string) *SummaryVec {
 	v := &SummaryVec{
 		SummaryOpts:    opts,
 		originalLabels: labels,
-		lazyMetric:     lazyMetric{},
+		lazyMetric:     lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	v.lazyInit(v, fqName)
 	return v

staging/src/k8s.io/component-base/metrics/timing_histogram.go

@@ -57,7 +57,7 @@ func NewTestableTimingHistogram(nowFunc func() time.Time, opts *TimingHistogramO
 	h := &TimingHistogram{
 		TimingHistogramOpts: opts,
 		nowFunc:             nowFunc,
-		lazyMetric:          lazyMetric{},
+		lazyMetric:          lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	h.setPrometheusHistogram(noopMetric{})
 	h.lazyInit(h, BuildFQName(opts.Namespace, opts.Subsystem, opts.Name))
@@ -136,7 +136,7 @@ func NewTestableTimingHistogramVec(nowFunc func() time.Time, opts *TimingHistogr
 		TimingHistogramOpts: opts,
 		nowFunc:             nowFunc,
 		originalLabels:      labels,
-		lazyMetric:          lazyMetric{},
+		lazyMetric:          lazyMetric{stabilityLevel: opts.StabilityLevel},
 	}
 	v.lazyInit(v, fqName)
 	return v