record event on endpoint update failure

pkg/controller/endpoint/BUILD

@@ -29,9 +29,12 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//staging/src/k8s.io/client-go/informers/core/v1:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
+        "//staging/src/k8s.io/client-go/kubernetes/scheme:go_default_library",
+        "//staging/src/k8s.io/client-go/kubernetes/typed/core/v1:go_default_library",
         "//staging/src/k8s.io/client-go/listers/core/v1:go_default_library",
         "//staging/src/k8s.io/client-go/tools/cache:go_default_library",
         "//staging/src/k8s.io/client-go/tools/leaderelection/resourcelock:go_default_library",
+        "//staging/src/k8s.io/client-go/tools/record:go_default_library",
         "//staging/src/k8s.io/client-go/util/workqueue:go_default_library",
         "//vendor/k8s.io/klog:go_default_library",
     ],

pkg/controller/endpoint/endpoints_controller.go

@@ -32,17 +32,19 @@ import (
 	"k8s.io/apimachinery/pkg/util/wait"
 	coreinformers "k8s.io/client-go/informers/core/v1"
 	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/kubernetes/scheme"
+	v1core "k8s.io/client-go/kubernetes/typed/core/v1"
 	corelisters "k8s.io/client-go/listers/core/v1"
 	"k8s.io/client-go/tools/cache"
 	"k8s.io/client-go/tools/leaderelection/resourcelock"
+	"k8s.io/client-go/tools/record"
 	"k8s.io/client-go/util/workqueue"
+	"k8s.io/klog"
 	"k8s.io/kubernetes/pkg/api/v1/endpoints"
 	podutil "k8s.io/kubernetes/pkg/api/v1/pod"
 	api "k8s.io/kubernetes/pkg/apis/core"
 	"k8s.io/kubernetes/pkg/controller"
 	"k8s.io/kubernetes/pkg/util/metrics"
-
-	"k8s.io/klog"
 )
 
 const (
@@ -71,6 +73,11 @@ const (
 // NewEndpointController returns a new *EndpointController.
 func NewEndpointController(podInformer coreinformers.PodInformer, serviceInformer coreinformers.ServiceInformer,
 	endpointsInformer coreinformers.EndpointsInformer, client clientset.Interface) *EndpointController {
+	broadcaster := record.NewBroadcaster()
+	broadcaster.StartLogging(klog.Infof)
+	broadcaster.StartRecordingToSink(&v1core.EventSinkImpl{Interface: client.CoreV1().Events("")})
+	recorder := broadcaster.NewRecorder(scheme.Scheme, v1.EventSource{Component: "endpoint-controller"})
+
 	if client != nil && client.CoreV1().RESTClient().GetRateLimiter() != nil {
 		metrics.RegisterMetricAndTrackRateLimiterUsage("endpoint_controller", client.CoreV1().RESTClient().GetRateLimiter())
 	}
@@ -101,12 +108,16 @@ func NewEndpointController(podInformer coreinformers.PodInformer, serviceInforme
 	e.endpointsLister = endpointsInformer.Lister()
 	e.endpointsSynced = endpointsInformer.Informer().HasSynced
 
+	e.eventBroadcaster = broadcaster
+	e.eventRecorder = recorder
 	return e
 }
 
 // EndpointController manages selector-based service endpoints.
 type EndpointController struct {
-	client clientset.Interface
+	client           clientset.Interface
+	eventBroadcaster record.EventBroadcaster
+	eventRecorder    record.EventRecorder
 
 	// serviceLister is able to list/get services and is populated by the shared informer passed to
 	// NewEndpointController.
@@ -522,6 +533,13 @@ func (e *EndpointController) syncService(key string) error {
 			// Given the frequency of 1, we log at a lower level.
 			klog.V(5).Infof("Forbidden from creating endpoints: %v", err)
 		}
+
+		if createEndpoints {
+			e.eventRecorder.Eventf(newEndpoints, v1.EventTypeWarning, "FailedToCreateEndpoint", "Failed to create endpoint for service %v/%v: %v", service.Namespace, service.Name, err)
+		} else {
+			e.eventRecorder.Eventf(newEndpoints, v1.EventTypeWarning, "FailedToUpdateEndpoint", "Failed to update endpoint %v/%v: %v", service.Namespace, service.Name, err)
+		}
+
 		return err
 	}
 	return nil