Use controller framework in HPA controller.

Ref #22174

cmd/kube-controller-manager/app/controllermanager.go

@@ -284,8 +284,8 @@ func StartControllers(s *options.CMServer, kubeClient *client.Client, kubeconfig
 				metrics.DefaultHeapsterService,
 				metrics.DefaultHeapsterPort,
 			)
-			podautoscaler.NewHorizontalController(hpaClient.Core(), hpaClient.Extensions(), hpaClient, metricsClient).
+			go podautoscaler.NewHorizontalController(hpaClient.Core(), hpaClient.Extensions(), hpaClient, metricsClient, s.HorizontalPodAutoscalerSyncPeriod.Duration).
-				Run(s.HorizontalPodAutoscalerSyncPeriod.Duration)
+				Run(wait.NeverStop)
 		}
 
 		if containsResource(resources, "daemonsets") {

contrib/mesos/pkg/controllermanager/controllermanager.go

@@ -232,8 +232,8 @@ func (s *CMServer) Run(_ []string) error {
 				metrics.DefaultHeapsterService,
 				metrics.DefaultHeapsterPort,
 			)
-			podautoscaler.NewHorizontalController(hpaClient.Core(), hpaClient.Extensions(), hpaClient, metricsClient).
+			go podautoscaler.NewHorizontalController(hpaClient.Core(), hpaClient.Extensions(), hpaClient, metricsClient, s.HorizontalPodAutoscalerSyncPeriod.Duration).
-				Run(s.HorizontalPodAutoscalerSyncPeriod.Duration)
+				Run(wait.NeverStop)
 		}
 
 		if containsResource(resources, "daemonsets") {

pkg/controller/podautoscaler/horizontal.go

@@ -27,11 +27,15 @@ import (
 	"k8s.io/kubernetes/pkg/api/resource"
 	"k8s.io/kubernetes/pkg/api/unversioned"
 	"k8s.io/kubernetes/pkg/apis/extensions"
+	"k8s.io/kubernetes/pkg/client/cache"
 	"k8s.io/kubernetes/pkg/client/record"
 	unversionedcore "k8s.io/kubernetes/pkg/client/typed/generated/core/unversioned"
 	unversionedextensions "k8s.io/kubernetes/pkg/client/typed/generated/extensions/unversioned"
+	"k8s.io/kubernetes/pkg/controller/framework"
 	"k8s.io/kubernetes/pkg/controller/podautoscaler/metrics"
-	"k8s.io/kubernetes/pkg/util/wait"
+	"k8s.io/kubernetes/pkg/runtime"
+	utilruntime "k8s.io/kubernetes/pkg/util/runtime"
+	"k8s.io/kubernetes/pkg/watch"
 )
 
 const (
@@ -51,33 +55,70 @@ type HorizontalController struct {
 
 	metricsClient metrics.MetricsClient
 	eventRecorder record.EventRecorder
+
+	// A store of HPA objects, populated by the controller.
+	store cache.Store
+	// Watches changes to all HPA objects.
+	controller *framework.Controller
 }
 
 var downscaleForbiddenWindow = 5 * time.Minute
 var upscaleForbiddenWindow = 3 * time.Minute
 
-func NewHorizontalController(evtNamespacer unversionedcore.EventsGetter, scaleNamespacer unversionedextensions.ScalesGetter, hpaNamespacer unversionedextensions.HorizontalPodAutoscalersGetter, metricsClient metrics.MetricsClient) *HorizontalController {
+func NewHorizontalController(evtNamespacer unversionedcore.EventsGetter, scaleNamespacer unversionedextensions.ScalesGetter, hpaNamespacer unversionedextensions.HorizontalPodAutoscalersGetter, metricsClient metrics.MetricsClient, resyncPeriod time.Duration) *HorizontalController {
 	broadcaster := record.NewBroadcaster()
 	broadcaster.StartRecordingToSink(&unversionedcore.EventSinkImpl{evtNamespacer.Events("")})
 	recorder := broadcaster.NewRecorder(api.EventSource{Component: "horizontal-pod-autoscaler"})
 
-	return &HorizontalController{
+	controller := &HorizontalController{
 		metricsClient:   metricsClient,
 		eventRecorder:   recorder,
 		scaleNamespacer: scaleNamespacer,
 		hpaNamespacer:   hpaNamespacer,
 	}
+
+	controller.store, controller.controller = framework.NewInformer(
+		&cache.ListWatch{
+			ListFunc: func(options api.ListOptions) (runtime.Object, error) {
+				return controller.hpaNamespacer.HorizontalPodAutoscalers(api.NamespaceAll).List(options)
+			},
+			WatchFunc: func(options api.ListOptions) (watch.Interface, error) {
+				return controller.hpaNamespacer.HorizontalPodAutoscalers(api.NamespaceAll).Watch(options)
+			},
+		},
+		&extensions.HorizontalPodAutoscaler{},
+		resyncPeriod,
+		framework.ResourceEventHandlerFuncs{
+			AddFunc: func(obj interface{}) {
+				hpa := obj.(*extensions.HorizontalPodAutoscaler)
+				err := controller.reconcileAutoscaler(hpa)
+				if err != nil {
+					glog.Warningf("Failed to reconcile %s: %v", hpa.Name, err)
+				}
+			},
+			UpdateFunc: func(old, cur interface{}) {
+				hpa := cur.(*extensions.HorizontalPodAutoscaler)
+				err := controller.reconcileAutoscaler(hpa)
+				if err != nil {
+					glog.Warningf("Failed to reconcile %s: %v", hpa.Name, err)
+				}
+			},
+			// We are not interested in deletions.
+		},
+	)
+
+	return controller
 }
 
-func (a *HorizontalController) Run(syncPeriod time.Duration) {
+func (a *HorizontalController) Run(stopCh <-chan struct{}) {
-	go wait.Until(func() {
+	defer utilruntime.HandleCrash()
-		if err := a.reconcileAutoscalers(); err != nil {
+	glog.Infof("Starting HPA Controller")
-			glog.Errorf("Couldn't reconcile horizontal pod autoscalers: %v", err)
+	go a.controller.Run(stopCh)
-		}
+	<-stopCh
-	}, syncPeriod, wait.NeverStop)
+	glog.Infof("Shutting down HPA Controller")
 }
 
-func (a *HorizontalController) computeReplicasForCPUUtilization(hpa extensions.HorizontalPodAutoscaler, scale *extensions.Scale) (int, *int, time.Time, error) {
+func (a *HorizontalController) computeReplicasForCPUUtilization(hpa *extensions.HorizontalPodAutoscaler, scale *extensions.Scale) (int, *int, time.Time, error) {
 	targetUtilization := defaultTargetCPUUtilizationPercentage
 	if hpa.Spec.CPUUtilization != nil {
 		targetUtilization = hpa.Spec.CPUUtilization.TargetPercentage
@@ -87,7 +128,7 @@ func (a *HorizontalController) computeReplicasForCPUUtilization(hpa extensions.H
 
 	// TODO: what to do on partial errors (like metrics obtained for 75% of pods).
 	if err != nil {
-		a.eventRecorder.Event(&hpa, api.EventTypeWarning, "FailedGetMetrics", err.Error())
+		a.eventRecorder.Event(hpa, api.EventTypeWarning, "FailedGetMetrics", err.Error())
 		return 0, nil, time.Time{}, fmt.Errorf("failed to get cpu utilization: %v", err)
 	}
 
@@ -103,7 +144,7 @@ func (a *HorizontalController) computeReplicasForCPUUtilization(hpa extensions.H
 // extensions.CustomMetricsTargetList.
 // Returns number of replicas, status string (also json-serialized extensions.CustomMetricsCurrentStatusList),
 // last timestamp of the metrics involved in computations or error, if occurred.
-func (a *HorizontalController) computeReplicasForCustomMetrics(hpa extensions.HorizontalPodAutoscaler, scale *extensions.Scale,
+func (a *HorizontalController) computeReplicasForCustomMetrics(hpa *extensions.HorizontalPodAutoscaler, scale *extensions.Scale,
 	cmAnnotation string) (int, string, time.Time, error) {
 
 	currentReplicas := scale.Status.Replicas
@@ -130,7 +171,7 @@ func (a *HorizontalController) computeReplicasForCustomMetrics(hpa extensions.Ho
 		value, currentTimestamp, err := a.metricsClient.GetCustomMetric(customMetricTarget.Name, hpa.Namespace, scale.Status.Selector)
 		// TODO: what to do on partial errors (like metrics obtained for 75% of pods).
 		if err != nil {
-			a.eventRecorder.Event(&hpa, api.EventTypeWarning, "FailedGetCustomMetrics", err.Error())
+			a.eventRecorder.Event(hpa, api.EventTypeWarning, "FailedGetCustomMetrics", err.Error())
 			return 0, "", time.Time{}, fmt.Errorf("failed to get custom metric value: %v", err)
 		}
 		floatTarget := float64(customMetricTarget.TargetValue.MilliValue()) / 1000.0
@@ -163,12 +204,12 @@ func (a *HorizontalController) computeReplicasForCustomMetrics(hpa extensions.Ho
 	return replicas, string(byteStatusList), timestamp, nil
 }
 
-func (a *HorizontalController) reconcileAutoscaler(hpa extensions.HorizontalPodAutoscaler) error {
+func (a *HorizontalController) reconcileAutoscaler(hpa *extensions.HorizontalPodAutoscaler) error {
 	reference := fmt.Sprintf("%s/%s/%s", hpa.Spec.ScaleRef.Kind, hpa.Namespace, hpa.Spec.ScaleRef.Name)
 
 	scale, err := a.scaleNamespacer.Scales(hpa.Namespace).Get(hpa.Spec.ScaleRef.Kind, hpa.Spec.ScaleRef.Name)
 	if err != nil {
-		a.eventRecorder.Event(&hpa, api.EventTypeWarning, "FailedGetScale", err.Error())
+		a.eventRecorder.Event(hpa, api.EventTypeWarning, "FailedGetScale", err.Error())
 		return fmt.Errorf("failed to query scale subresource for %s: %v", reference, err)
 	}
 	currentReplicas := scale.Status.Replicas
@@ -198,7 +239,7 @@ func (a *HorizontalController) reconcileAutoscaler(hpa extensions.HorizontalPodA
 			cpuDesiredReplicas, cpuCurrentUtilization, cpuTimestamp, err = a.computeReplicasForCPUUtilization(hpa, scale)
 			if err != nil {
 				a.updateCurrentReplicasInStatus(hpa, currentReplicas)
-				a.eventRecorder.Event(&hpa, api.EventTypeWarning, "FailedComputeReplicas", err.Error())
+				a.eventRecorder.Event(hpa, api.EventTypeWarning, "FailedComputeReplicas", err.Error())
 				return fmt.Errorf("failed to compute desired number of replicas based on CPU utilization for %s: %v", reference, err)
 			}
 		}
@@ -207,7 +248,7 @@ func (a *HorizontalController) reconcileAutoscaler(hpa extensions.HorizontalPodA
 			cmDesiredReplicas, cmStatus, cmTimestamp, err = a.computeReplicasForCustomMetrics(hpa, scale, cmAnnotation)
 			if err != nil {
 				a.updateCurrentReplicasInStatus(hpa, currentReplicas)
-				a.eventRecorder.Event(&hpa, api.EventTypeWarning, "FailedComputeCMReplicas", err.Error())
+				a.eventRecorder.Event(hpa, api.EventTypeWarning, "FailedComputeCMReplicas", err.Error())
 				return fmt.Errorf("failed to compute desired number of replicas based on Custom Metrics for %s: %v", reference, err)
 			}
 		}
@@ -240,10 +281,10 @@ func (a *HorizontalController) reconcileAutoscaler(hpa extensions.HorizontalPodA
 		scale.Spec.Replicas = desiredReplicas
 		_, err = a.scaleNamespacer.Scales(hpa.Namespace).Update(hpa.Spec.ScaleRef.Kind, scale)
 		if err != nil {
-			a.eventRecorder.Eventf(&hpa, api.EventTypeWarning, "FailedRescale", "New size: %d; error: %v", desiredReplicas, err.Error())
+			a.eventRecorder.Eventf(hpa, api.EventTypeWarning, "FailedRescale", "New size: %d; error: %v", desiredReplicas, err.Error())
 			return fmt.Errorf("failed to rescale %s: %v", reference, err)
 		}
-		a.eventRecorder.Eventf(&hpa, api.EventTypeNormal, "SuccessfulRescale", "New size: %d", desiredReplicas)
+		a.eventRecorder.Eventf(hpa, api.EventTypeNormal, "SuccessfulRescale", "New size: %d", desiredReplicas)
 		glog.Infof("Successfull rescale of %s, old size: %d, new size: %d",
 			hpa.Name, currentReplicas, desiredReplicas)
 	} else {
@@ -253,7 +294,7 @@ func (a *HorizontalController) reconcileAutoscaler(hpa extensions.HorizontalPodA
 	return a.updateStatus(hpa, currentReplicas, desiredReplicas, cpuCurrentUtilization, cmStatus, rescale)
 }
 
-func shouldScale(hpa extensions.HorizontalPodAutoscaler, currentReplicas, desiredReplicas int, timestamp time.Time) bool {
+func shouldScale(hpa *extensions.HorizontalPodAutoscaler, currentReplicas, desiredReplicas int, timestamp time.Time) bool {
 	if desiredReplicas != currentReplicas {
 		// Going down only if the usageRatio dropped significantly below the target
 		// and there was no rescaling in the last downscaleForbiddenWindow.
@@ -274,14 +315,14 @@ func shouldScale(hpa extensions.HorizontalPodAutoscaler, currentReplicas, desire
 	return false
 }
 
-func (a *HorizontalController) updateCurrentReplicasInStatus(hpa extensions.HorizontalPodAutoscaler, currentReplicas int) {
+func (a *HorizontalController) updateCurrentReplicasInStatus(hpa *extensions.HorizontalPodAutoscaler, currentReplicas int) {
 	err := a.updateStatus(hpa, currentReplicas, hpa.Status.DesiredReplicas, hpa.Status.CurrentCPUUtilizationPercentage, hpa.Annotations[HpaCustomMetricsStatusAnnotationName], false)
 	if err != nil {
 		glog.Errorf("%v", err)
 	}
 }
 
-func (a *HorizontalController) updateStatus(hpa extensions.HorizontalPodAutoscaler, currentReplicas, desiredReplicas int, cpuCurrentUtilization *int, cmStatus string, rescale bool) error {
+func (a *HorizontalController) updateStatus(hpa *extensions.HorizontalPodAutoscaler, currentReplicas, desiredReplicas int, cpuCurrentUtilization *int, cmStatus string, rescale bool) error {
 	hpa.Status = extensions.HorizontalPodAutoscalerStatus{
 		CurrentReplicas:                 currentReplicas,
 		DesiredReplicas:                 desiredReplicas,
@@ -297,25 +338,11 @@ func (a *HorizontalController) updateStatus(hpa extensions.HorizontalPodAutoscal
 		hpa.Status.LastScaleTime = &now
 	}
 
-	_, err := a.hpaNamespacer.HorizontalPodAutoscalers(hpa.Namespace).UpdateStatus(&hpa)
+	_, err := a.hpaNamespacer.HorizontalPodAutoscalers(hpa.Namespace).UpdateStatus(hpa)
 	if err != nil {
-		a.eventRecorder.Event(&hpa, api.EventTypeWarning, "FailedUpdateStatus", err.Error())
+		a.eventRecorder.Event(hpa, api.EventTypeWarning, "FailedUpdateStatus", err.Error())
 		return fmt.Errorf("failed to update status for %s: %v", hpa.Name, err)
 	}
-	return nil
+	glog.V(2).Infof("Successfully updated status for %s", hpa.Name)
-}
-
-func (a *HorizontalController) reconcileAutoscalers() error {
-	ns := api.NamespaceAll
-	list, err := a.hpaNamespacer.HorizontalPodAutoscalers(ns).List(api.ListOptions{})
-	if err != nil {
-		return fmt.Errorf("error listing nodes: %v", err)
-	}
-	for _, hpa := range list.Items {
-		err := a.reconcileAutoscaler(hpa)
-		if err != nil {
-			glog.Warningf("Failed to reconcile %s: %v", hpa.Name, err)
-		}
-	}
 	return nil
 }

pkg/controller/podautoscaler/horizontal_test.go

@@ -33,9 +33,12 @@ import (
 	"k8s.io/kubernetes/pkg/client/unversioned/testclient"
 	"k8s.io/kubernetes/pkg/controller/podautoscaler/metrics"
 	"k8s.io/kubernetes/pkg/runtime"
+	"k8s.io/kubernetes/pkg/util/wait"
+	"k8s.io/kubernetes/pkg/watch"
 
 	heapster "k8s.io/heapster/api/v1/types"
 
+	"github.com/golang/glog"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -215,11 +218,11 @@ func (tc *testCase) prepareTestClient(t *testing.T) *fake.Clientset {
 		assert.Equal(t, namespace, obj.Namespace)
 		assert.Equal(t, hpaName, obj.Name)
 		assert.Equal(t, tc.desiredReplicas, obj.Status.DesiredReplicas)
-		tc.statusUpdated = true
 		if tc.verifyCPUCurrent {
 			assert.NotNil(t, obj.Status.CurrentCPUUtilizationPercentage)
 			assert.Equal(t, tc.CPUCurrent, *obj.Status.CurrentCPUUtilizationPercentage)
 		}
+		tc.statusUpdated = true
 		return true, obj, nil
 	})
 
@@ -233,6 +236,9 @@ func (tc *testCase) prepareTestClient(t *testing.T) *fake.Clientset {
 		return true, obj, nil
 	})
 
+	fakeWatch := watch.NewFake()
+	fakeClient.AddWatchReactor("*", core.DefaultWatchReactor(fakeWatch, nil))
+
 	return fakeClient
 }
 
@@ -247,13 +253,19 @@ func (tc *testCase) verifyResults(t *testing.T) {
 func (tc *testCase) runTest(t *testing.T) {
 	testClient := tc.prepareTestClient(t)
 	metricsClient := metrics.NewHeapsterMetricsClient(testClient, metrics.DefaultHeapsterNamespace, metrics.DefaultHeapsterScheme, metrics.DefaultHeapsterService, metrics.DefaultHeapsterPort)
-	hpaController := NewHorizontalController(testClient.Core(), testClient.Extensions(), testClient.Extensions(), metricsClient)
+	hpaController := NewHorizontalController(testClient.Core(), testClient.Extensions(), testClient.Extensions(), metricsClient, 0)
-	err := hpaController.reconcileAutoscalers()
+	stop := make(chan struct{})
-	assert.Equal(t, nil, err)
+	defer close(stop)
+	go hpaController.Run(stop)
 	if tc.verifyEvents {
 		// We need to wait for events to be broadcasted (sleep for longer than record.sleepDuration).
 		time.Sleep(12 * time.Second)
 	}
+	// Each iteration for an HPA object ends with updating status.
+	wait.Poll(1*time.Second, 30*time.Second, func() (done bool, err error) {
+		glog.Infof("Status value: ", tc.statusUpdated)
+		return tc.statusUpdated, nil
+	})
 	tc.verifyResults(t)
 }