ignore update events for endpoints used for leader election (#390)

Author: andrewsykim

app/controllers/network_routes_controller.go

@@ -1490,6 +1490,10 @@ func (nrc *NetworkRoutingController) OnEndpointsUpdate(obj interface{}) {
 		return
 	}
 
+	if isEndpointsForLeaderElection(ep) {
+		return
+	}
+
 	svc, err := nrc.serviceForEndpoints(ep)
 	if err != nil {
 		glog.Errorf("failed to convert endpoints resource to service: %s", err)

app/controllers/network_services_controller.go

@@ -49,6 +49,8 @@ const (
 	svcHairpinAnnotation   = "kube-router.io/service.hairpin"
 	svcLocalAnnotation     = "kube-router.io/service.local"
 	svcSkipLbIpsAnnotation = "kube-router.io/service.skiplbips"
+
+	LeaderElectionRecordAnnotationKey = "control-plane.alpha.kubernetes.io/leader"
 )
 
 var (
@@ -353,6 +355,16 @@ func (nsc *NetworkServicesController) OnEndpointsUpdate(obj interface{}) {
 
 	glog.V(1).Info("Received endpoints update from watch API")
 
+	ep, ok := obj.(*api.Endpoints)
+	if !ok {
+		glog.Error("could not convert endpoints update object to *v1.Endpoints")
+		return
+	}
+
+	if isEndpointsForLeaderElection(ep) {
+		return
+	}
+
 	// build new endpoints map to reflect the change
 	newEndpointsMap := nsc.buildEndpointsInfo()
 
@@ -1617,6 +1629,11 @@ func (ln *linuxNetworking) setupRoutesForExternalIPForDSR(serviceInfoMap service
 	return nil
 }
 
+func isEndpointsForLeaderElection(ep *api.Endpoints) bool {
+	_, isLeaderElection := ep.Annotations[LeaderElectionRecordAnnotationKey]
+	return isLeaderElection
+}
+
 // unique identifier for a load-balanced service (namespace + name + portname)
 func generateServiceId(namespace, svcName, port string) string {
 	return namespace + "-" + svcName + "-" + port