aggregator: separate out status controller metrics

Signed-off-by: Dr. Stefan Schimanski <stefan.schimanski@gmail.com>

staging/src/k8s.io/kube-aggregator/pkg/apiserver/apiserver.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"sync"
 	"time"
 
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
@@ -37,6 +38,7 @@ import (
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/transport"
+	"k8s.io/component-base/metrics/legacyregistry"
 	"k8s.io/component-base/tracing"
 	v1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
 	v1helper "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1/helper"
@@ -50,10 +52,14 @@ import (
 	openapiv3controller "k8s.io/kube-aggregator/pkg/controllers/openapiv3"
 	openapiv3aggregator "k8s.io/kube-aggregator/pkg/controllers/openapiv3/aggregator"
 	statuscontrollers "k8s.io/kube-aggregator/pkg/controllers/status"
+	availabilitymetrics "k8s.io/kube-aggregator/pkg/controllers/status/metrics"
 	apiservicerest "k8s.io/kube-aggregator/pkg/registry/apiservice/rest"
 	openapicommon "k8s.io/kube-openapi/pkg/common"
 )
 
+// making sure we only register metrics once into legacy registry
+var registerIntoLegacyRegistryOnce sync.Once
+
 func init() {
 	// we need to add the options (like ListOptions) to empty v1
 	metav1.AddToGroupVersion(aggregatorscheme.Scheme, schema.GroupVersion{Group: "", Version: "v1"})
@@ -314,6 +320,14 @@ func (c completedConfig) NewWithDelegate(delegationTarget genericapiserver.Deleg
 		})
 	}
 
+	// create shared (remote and local) availability metrics
+	// TODO: decouple from legacyregistry
+	metrics := availabilitymetrics.New()
+	registerIntoLegacyRegistryOnce.Do(func() { err = metrics.Register(legacyregistry.Register, legacyregistry.CustomRegister) })
+	if err != nil {
+		return nil, err
+	}
+
 	// If the AvailableConditionController is disabled, we don't need to start the informers
 	// and the controller.
 	if !c.ExtraConfig.DisableAvailableConditionController {
@@ -325,6 +339,7 @@ func (c completedConfig) NewWithDelegate(delegationTarget genericapiserver.Deleg
 			proxyTransportDial,
 			(func() ([]byte, []byte))(s.proxyCurrentCertKeyContent),
 			s.serviceResolver,
+			metrics,
 		)
 		if err != nil {
 			return nil, err

staging/src/k8s.io/kube-aggregator/pkg/controllers/status/available_controller.go

@@ -39,7 +39,6 @@ import (
 	"k8s.io/client-go/tools/cache"
 	"k8s.io/client-go/transport"
 	"k8s.io/client-go/util/workqueue"
-	"k8s.io/component-base/metrics/legacyregistry"
 	"k8s.io/klog/v2"
 	apiregistrationv1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
 	apiregistrationv1apihelper "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1/helper"
@@ -47,11 +46,9 @@ import (
 	informers "k8s.io/kube-aggregator/pkg/client/informers/externalversions/apiregistration/v1"
 	listers "k8s.io/kube-aggregator/pkg/client/listers/apiregistration/v1"
 	"k8s.io/kube-aggregator/pkg/controllers"
+	availabilitymetrics "k8s.io/kube-aggregator/pkg/controllers/status/metrics"
 )
 
-// making sure we only register metrics once into legacy registry
-var registerIntoLegacyRegistryOnce sync.Once
-
 type certKeyFunc func() ([]byte, []byte)
 
 // ServiceResolver knows how to convert a service reference into an actual location.
@@ -88,7 +85,7 @@ type AvailableConditionController struct {
 	cacheLock sync.RWMutex
 
 	// metrics registered into legacy registry
-	metrics *availabilityMetrics
+	metrics *availabilitymetrics.Metrics
 }
 
 // NewAvailableConditionController returns a new AvailableConditionController.
@@ -100,6 +97,7 @@ func NewAvailableConditionController(
 	proxyTransportDial *transport.DialHolder,
 	proxyCurrentCertKeyContent certKeyFunc,
 	serviceResolver ServiceResolver,
+	metrics *availabilitymetrics.Metrics,
 ) (*AvailableConditionController, error) {
 	c := &AvailableConditionController{
 		apiServiceClient: apiServiceClient,
@@ -116,7 +114,7 @@ func NewAvailableConditionController(
 		),
 		proxyTransportDial:         proxyTransportDial,
 		proxyCurrentCertKeyContent: proxyCurrentCertKeyContent,
-		metrics:                    newAvailabilityMetrics(),
+		metrics:                    metrics,
 	}
 
 	// resync on this one because it is low cardinality and rechecking the actual discovery
@@ -148,15 +146,6 @@ func NewAvailableConditionController(
 
 	c.syncFn = c.sync
 
-	// TODO: decouple from legacyregistry
-	var err error
-	registerIntoLegacyRegistryOnce.Do(func() {
-		err = c.metrics.Register(legacyregistry.Register, legacyregistry.CustomRegister)
-	})
-	if err != nil {
-		return nil, err
-	}
-
 	return c, nil
 }
 
@@ -385,7 +374,7 @@ func (c *AvailableConditionController) sync(key string) error {
 // apiservices. Doing that means we don't want to quickly issue no-op updates.
 func (c *AvailableConditionController) updateAPIServiceStatus(originalAPIService, newAPIService *apiregistrationv1.APIService) (*apiregistrationv1.APIService, error) {
 	// update this metric on every sync operation to reflect the actual state
-	c.setUnavailableGauge(newAPIService)
+	c.metrics.SetUnavailableGauge(newAPIService)
 
 	if equality.Semantic.DeepEqual(originalAPIService.Status, newAPIService.Status) {
 		return newAPIService, nil
@@ -412,7 +401,7 @@ func (c *AvailableConditionController) updateAPIServiceStatus(originalAPIService
 		return nil, err
 	}
 
-	c.setUnavailableCounter(originalAPIService, newAPIService)
+	c.metrics.SetUnavailableCounter(originalAPIService, newAPIService)
 	return newAPIService, nil
 }
 
@@ -599,28 +588,3 @@ func (c *AvailableConditionController) deleteEndpoints(obj interface{}) {
 		c.queue.Add(apiService)
 	}
 }
-
-// setUnavailableGauge set the metrics so that it reflect the current state base on availability of the given service
-func (c *AvailableConditionController) setUnavailableGauge(newAPIService *apiregistrationv1.APIService) {
-	if apiregistrationv1apihelper.IsAPIServiceConditionTrue(newAPIService, apiregistrationv1.Available) {
-		c.metrics.SetAPIServiceAvailable(newAPIService.Name)
-		return
-	}
-
-	c.metrics.SetAPIServiceUnavailable(newAPIService.Name)
-}
-
-// setUnavailableCounter increases the metrics only if the given service is unavailable and its APIServiceCondition has changed
-func (c *AvailableConditionController) setUnavailableCounter(originalAPIService, newAPIService *apiregistrationv1.APIService) {
-	wasAvailable := apiregistrationv1apihelper.IsAPIServiceConditionTrue(originalAPIService, apiregistrationv1.Available)
-	isAvailable := apiregistrationv1apihelper.IsAPIServiceConditionTrue(newAPIService, apiregistrationv1.Available)
-	statusChanged := isAvailable != wasAvailable
-
-	if statusChanged && !isAvailable {
-		reason := "UnknownReason"
-		if newCondition := apiregistrationv1apihelper.GetAPIServiceConditionByType(newAPIService, apiregistrationv1.Available); newCondition != nil {
-			reason = newCondition.Reason
-		}
-		c.metrics.UnavailableCounter(newAPIService.Name, reason).Inc()
-	}
-}

staging/src/k8s.io/kube-aggregator/pkg/controllers/status/available_controller_test.go

@@ -25,6 +25,7 @@ import (
 	"testing"
 	"time"
 
+	availabilitymetrics "k8s.io/kube-aggregator/pkg/controllers/status/metrics"
 	"k8s.io/utils/pointer"
 
 	v1 "k8s.io/api/core/v1"
@@ -133,7 +134,7 @@ func setupAPIServices(apiServices []*apiregistration.APIService) (*AvailableCond
 			workqueue.NewTypedItemExponentialFailureRateLimiter[string](5*time.Millisecond, 30*time.Second),
 			workqueue.TypedRateLimitingQueueConfig[string]{Name: "AvailableConditionController"},
 		),
-		metrics: newAvailabilityMetrics(),
+		metrics: availabilitymetrics.New(),
 	}
 	for _, svc := range apiServices {
 		c.addAPIService(svc)
@@ -395,7 +396,7 @@ func TestSync(t *testing.T) {
 				endpointsLister:            v1listers.NewEndpointsLister(endpointsIndexer),
 				serviceResolver:            &fakeServiceResolver{url: testServer.URL},
 				proxyCurrentCertKeyContent: func() ([]byte, []byte) { return emptyCert(), emptyCert() },
-				metrics:                    newAvailabilityMetrics(),
+				metrics:                    availabilitymetrics.New(),
 			}
 			c.sync(tc.apiServiceName)
 
@@ -447,7 +448,7 @@ func TestUpdateAPIServiceStatus(t *testing.T) {
 	fakeClient := fake.NewSimpleClientset()
 	c := AvailableConditionController{
 		apiServiceClient: fakeClient.ApiregistrationV1().(apiregistrationclient.APIServicesGetter),
-		metrics:          newAvailabilityMetrics(),
+		metrics:          availabilitymetrics.New(),
 	}
 
 	c.updateAPIServiceStatus(foo, foo)

staging/src/k8s.io/kube-aggregator/pkg/controllers/status/metrics/metrics.go

@@ -14,12 +14,14 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package apiserver
+package metrics
 
 import (
 	"sync"
 
 	"k8s.io/component-base/metrics"
+	apiregistrationv1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
+	apiregistrationv1apihelper "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1/helper"
 )
 
 /*
@@ -41,14 +43,14 @@ var (
 	)
 )
 
-type availabilityMetrics struct {
+type Metrics struct {
 	unavailableCounter *metrics.CounterVec
 
 	*availabilityCollector
 }
 
-func newAvailabilityMetrics() *availabilityMetrics {
+func New() *Metrics {
-	return &availabilityMetrics{
+	return &Metrics{
 		unavailableCounter: metrics.NewCounterVec(
 			&metrics.CounterOpts{
 				Name:           "aggregator_unavailable_apiservice_total",
@@ -62,7 +64,7 @@ func newAvailabilityMetrics() *availabilityMetrics {
 }
 
 // Register registers apiservice availability metrics.
-func (m *availabilityMetrics) Register(
+func (m *Metrics) Register(
 	registrationFunc func(metrics.Registerable) error,
 	customRegistrationFunc func(metrics.StableCollector) error,
 ) error {
@@ -80,7 +82,7 @@ func (m *availabilityMetrics) Register(
 }
 
 // UnavailableCounter returns a counter to track apiservices marked as unavailable.
-func (m *availabilityMetrics) UnavailableCounter(apiServiceName, reason string) metrics.CounterMetric {
+func (m *Metrics) UnavailableCounter(apiServiceName, reason string) metrics.CounterMetric {
 	return m.unavailableCounter.WithLabelValues(apiServiceName, reason)
 }
 
@@ -91,6 +93,31 @@ type availabilityCollector struct {
 	availabilities map[string]bool
 }
 
+// SetUnavailableGauge set the metrics so that it reflect the current state base on availability of the given service
+func (m *Metrics) SetUnavailableGauge(newAPIService *apiregistrationv1.APIService) {
+	if apiregistrationv1apihelper.IsAPIServiceConditionTrue(newAPIService, apiregistrationv1.Available) {
+		m.SetAPIServiceAvailable(newAPIService.Name)
+		return
+	}
+
+	m.SetAPIServiceUnavailable(newAPIService.Name)
+}
+
+// SetUnavailableCounter increases the metrics only if the given service is unavailable and its APIServiceCondition has changed
+func (m *Metrics) SetUnavailableCounter(originalAPIService, newAPIService *apiregistrationv1.APIService) {
+	wasAvailable := apiregistrationv1apihelper.IsAPIServiceConditionTrue(originalAPIService, apiregistrationv1.Available)
+	isAvailable := apiregistrationv1apihelper.IsAPIServiceConditionTrue(newAPIService, apiregistrationv1.Available)
+	statusChanged := isAvailable != wasAvailable
+
+	if statusChanged && !isAvailable {
+		reason := "UnknownReason"
+		if newCondition := apiregistrationv1apihelper.GetAPIServiceConditionByType(newAPIService, apiregistrationv1.Available); newCondition != nil {
+			reason = newCondition.Reason
+		}
+		m.UnavailableCounter(newAPIService.Name, reason).Inc()
+	}
+}
+
 // Check if apiServiceStatusCollector implements necessary interface.
 var _ metrics.StableCollector = &availabilityCollector{}
 

staging/src/k8s.io/kube-aggregator/pkg/controllers/status/metrics/metrics_test.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package apiserver
+package metrics
 
 import (
 	"strings"