use generic slis as entrypoint for healthcheck metrics

staging/src/k8s.io/component-base/metrics/prometheus/health/metrics.go → staging/src/k8s.io/component-base/metrics/prometheus/slis/metrics.go

@@ -14,14 +14,13 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package health
+package slis
 
 import (
 	"context"
 	"errors"
 
 	k8smetrics "k8s.io/component-base/metrics"
-	"k8s.io/component-base/metrics/legacyregistry"
 )
 
 type HealthcheckStatus string
@@ -64,32 +63,28 @@ var (
 	)
 	statuses  = []HealthcheckStatus{Success, Error, Pending}
 	statusSet = map[HealthcheckStatus]struct{}{Success: {}, Error: {}, Pending: {}}
-	checkSet  = map[HealthcheckType]struct{}{Livez: {}, Readyz: {}, Healthz: {}}
 )
 
-func init() {
-	legacyregistry.MustRegister(healthcheck)
-	legacyregistry.MustRegister(healthchecksTotal)
+func Register(registry k8smetrics.KubeRegistry) {
+	registry.Register(healthcheck)
+	registry.Register(healthchecksTotal)
 }
 
 func ResetHealthMetrics() {
 	healthcheck.Reset()
 	healthchecksTotal.Reset()
 }
 
-func ObserveHealthcheck(ctx context.Context, name string, healthcheckType HealthcheckType, status HealthcheckStatus) error {
+func ObserveHealthcheck(ctx context.Context, name string, healthcheckType string, status HealthcheckStatus) error {
 	if _, ok := statusSet[status]; !ok {
 		return errors.New("not a valid healthcheck status")
 	}
-	if _, ok := checkSet[healthcheckType]; !ok {
-		return errors.New("not a valid healthcheck type")
-	}
 	for _, s := range statuses {
 		if status != s {
-			healthcheck.WithContext(ctx).WithLabelValues(name, string(healthcheckType), string(s)).Set(0)
+			healthcheck.WithContext(ctx).WithLabelValues(name, healthcheckType, string(s)).Set(0)
 		}
 	}
-	healthchecksTotal.WithContext(ctx).WithLabelValues(name, string(healthcheckType), string(status)).Inc()
-	healthcheck.WithContext(ctx).WithLabelValues(name, string(healthcheckType), string(status)).Set(1)
+	healthchecksTotal.WithContext(ctx).WithLabelValues(name, healthcheckType, string(status)).Inc()
+	healthcheck.WithContext(ctx).WithLabelValues(name, healthcheckType, string(status)).Set(1)
 	return nil
 }

staging/src/k8s.io/component-base/metrics/prometheus/health/metrics_test.go → staging/src/k8s.io/component-base/metrics/prometheus/slis/metrics_test.go

@@ -14,14 +14,14 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package health
+package slis
 
 import (
 	"context"
 	"strings"
 	"testing"
 
-	"k8s.io/component-base/metrics/legacyregistry"
+	"k8s.io/component-base/metrics"
 	"k8s.io/component-base/metrics/testutil"
 )
 
@@ -30,8 +30,10 @@ var (
 )
 
 func TestObserveHealthcheck(t *testing.T) {
-	defer legacyregistry.Reset()
+	registry := metrics.NewKubeRegistry()
+	defer registry.Reset()
 	defer ResetHealthMetrics()
+	Register(registry)
 	initialState := Error
 	healthcheckName := "healthcheck-a"
 	initialOutput := `
@@ -47,14 +49,14 @@ func TestObserveHealthcheck(t *testing.T) {
 	testCases := []struct {
 		desc     string
 		name     string
-		hcType   HealthcheckType
+		hcType   string
 		hcStatus HealthcheckStatus
 		want     string
 	}{
 		{
 			desc:     "test pending",
 			name:     healthcheckName,
-			hcType:   Healthz,
+			hcType:   "healthz",
 			hcStatus: Pending,
 			want: `
         # HELP kubernetes_healthcheck [ALPHA] This metric records the result of a single healthcheck.
@@ -71,7 +73,7 @@ func TestObserveHealthcheck(t *testing.T) {
 		{
 			desc:     "test success",
 			name:     healthcheckName,
-			hcType:   Healthz,
+			hcType:   "healthz",
 			hcStatus: Success,
 			want: `
         # HELP kubernetes_healthcheck [ALPHA] This metric records the result of a single healthcheck.
@@ -95,15 +97,15 @@ func TestObserveHealthcheck(t *testing.T) {
 			if err != nil {
 				t.Errorf("unexpected err: %v", err)
 			}
-			if err := testutil.GatherAndCompare(legacyregistry.DefaultGatherer, strings.NewReader(initialOutput), testedMetrics...); err != nil {
+			if err := testutil.GatherAndCompare(registry, strings.NewReader(initialOutput), testedMetrics...); err != nil {
 				t.Fatal(err)
 			}
 			// now record that we successfully purge state
 			err = ObserveHealthcheck(context.Background(), test.name, test.hcType, test.hcStatus)
 			if err != nil {
 				t.Errorf("unexpected err: %v", err)
 			}
-			if err := testutil.GatherAndCompare(legacyregistry.DefaultGatherer, strings.NewReader(test.want), testedMetrics...); err != nil {
+			if err := testutil.GatherAndCompare(registry, strings.NewReader(test.want), testedMetrics...); err != nil {
 				t.Fatal(err)
 			}
 		})

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

@@ -0,0 +1,27 @@
+/*
+Copyright 2020 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 slis
+
+import (
+	"k8s.io/component-base/metrics"
+)
+
+var (
+	// Registry exposes the SLI registry so that additional SLIs can be
+	// added on a per-component basis.
+	Registry = metrics.NewKubeRegistry()
+)

staging/src/k8s.io/component-base/metrics/prometheus/slis/routes.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2020 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 slis
+
+import (
+	"net/http"
+	"sync"
+
+	"k8s.io/component-base/metrics"
+)
+
+var (
+	installOnce          = sync.Once{}
+	installWithResetOnce = sync.Once{}
+)
+
+type mux interface {
+	Handle(path string, handler http.Handler)
+}
+
+type SLIMetrics struct{}
+
+// Install adds the DefaultMetrics handler
+func (s SLIMetrics) Install(m mux) {
+	installOnce.Do(func() {
+		Register(Registry)
+		m.Handle("/metrics/slis", metrics.HandlerFor(Registry, metrics.HandlerOpts{}))
+	})
+}
+
+type SLIMetricsWithReset struct{}
+
+// Install adds the DefaultMetrics handler
+func (s SLIMetricsWithReset) Install(m mux) {
+	installWithResetOnce.Do(func() {
+		Register(Registry)
+		m.Handle("/metrics/slis", metrics.HandlerWithReset(Registry, metrics.HandlerOpts{}))
+	})
+}

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

@@ -145,6 +145,12 @@ type Gatherer interface {
 	prometheus.Gatherer
 }
 
+// Registerer is the interface for the part of a registry in charge of registering
+// the collected metrics.
+type Registerer interface {
+	prometheus.Registerer
+}
+
 // GaugeFunc is a Gauge whose value is determined at collect time by calling a
 // provided function.
 //