Trigger syncIngress on Service addition/deletion #7346

Normally Ingress sinchronization for Services is triggered when
corresponding Service's Endpoints are added, deleted or modified.
Services of type ExternalName, however, do not have any endpoints
and hence do not trigger Ingress synchronization as only Update
events are being watched. This commit makes sure that Update and
Delete Service events also enqueue a syncIngress task.

internal/ingress/controller/store/store.go

@@ -592,6 +592,24 @@ func New(
 	}
 
 	serviceHandler := cache.ResourceEventHandlerFuncs{
+		AddFunc: func(obj interface{}) {
+			svc := obj.(*corev1.Service)
+			if svc.Spec.Type == corev1.ServiceTypeExternalName {
+				updateCh.In() <- Event{
+					Type: CreateEvent,
+					Obj:  obj,
+				}
+			}
+		},
+		DeleteFunc: func(obj interface{}) {
+			svc := obj.(*corev1.Service)
+			if svc.Spec.Type == corev1.ServiceTypeExternalName {
+				updateCh.In() <- Event{
+					Type: DeleteEvent,
+					Obj:  obj,
+				}
+			}
+		},
 		UpdateFunc: func(old, cur interface{}) {
 			oldSvc := old.(*corev1.Service)
 			curSvc := cur.(*corev1.Service)

test/e2e/servicebackend/service_externalname.go

@@ -34,6 +34,27 @@ import (
 	"k8s.io/ingress-nginx/test/e2e/framework"
 )
 
+func buildHTTPBinExternalNameService(f *framework.Framework, portName string) *core.Service {
+	return &core.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      framework.HTTPBinService,
+			Namespace: f.Namespace,
+		},
+		Spec: corev1.ServiceSpec{
+			ExternalName: "httpbin.org",
+			Type:         corev1.ServiceTypeExternalName,
+			Ports: []corev1.ServicePort{
+				{
+					Name:       portName,
+					Port:       80,
+					TargetPort: intstr.FromInt(80),
+					Protocol:   "TCP",
+				},
+			},
+		},
+	}
+}
+
 var _ = framework.IngressNginxDescribe("[Service] Type ExternalName", func() {
 	f := framework.NewDefaultFramework("type-externalname")
 
@@ -107,24 +128,7 @@ var _ = framework.IngressNginxDescribe("[Service] Type ExternalName", func() {
 	ginkgo.It("should return 200 for service type=ExternalName with a port defined", func() {
 		host := "echo"
 
-		svc := &core.Service{
-			ObjectMeta: metav1.ObjectMeta{
-				Name:      framework.HTTPBinService,
-				Namespace: f.Namespace,
-			},
-			Spec: corev1.ServiceSpec{
-				ExternalName: "httpbin.org",
-				Type:         corev1.ServiceTypeExternalName,
-				Ports: []corev1.ServicePort{
-					{
-						Name:       host,
-						Port:       80,
-						TargetPort: intstr.FromInt(80),
-						Protocol:   "TCP",
-					},
-				},
-			},
-		}
+		svc := buildHTTPBinExternalNameService(f, host)
 		f.EnsureService(svc)
 
 		annotations := map[string]string{
@@ -179,24 +183,7 @@ var _ = framework.IngressNginxDescribe("[Service] Type ExternalName", func() {
 	ginkgo.It("should return 200 for service type=ExternalName using a port name", func() {
 		host := "echo"
 
-		svc := &core.Service{
-			ObjectMeta: metav1.ObjectMeta{
-				Name:      framework.HTTPBinService,
-				Namespace: f.Namespace,
-			},
-			Spec: corev1.ServiceSpec{
-				ExternalName: "httpbin.org",
-				Type:         corev1.ServiceTypeExternalName,
-				Ports: []corev1.ServicePort{
-					{
-						Name:       host,
-						Port:       80,
-						TargetPort: intstr.FromInt(80),
-						Protocol:   "TCP",
-					},
-				},
-			},
-		}
+		svc := buildHTTPBinExternalNameService(f, host)
 		f.EnsureService(svc)
 
 		annotations := map[string]string{
@@ -252,24 +239,7 @@ var _ = framework.IngressNginxDescribe("[Service] Type ExternalName", func() {
 	ginkgo.It("should update the external name after a service update", func() {
 		host := "echo"
 
-		svc := &core.Service{
-			ObjectMeta: metav1.ObjectMeta{
-				Name:      framework.HTTPBinService,
-				Namespace: f.Namespace,
-			},
-			Spec: corev1.ServiceSpec{
-				ExternalName: "httpbin.org",
-				Type:         corev1.ServiceTypeExternalName,
-				Ports: []corev1.ServicePort{
-					{
-						Name:       host,
-						Port:       80,
-						TargetPort: intstr.FromInt(80),
-						Protocol:   "TCP",
-					},
-				},
-			},
-		}
+		svc := buildHTTPBinExternalNameService(f, host)
 		f.EnsureService(svc)
 
 		annotations := map[string]string{
@@ -320,4 +290,51 @@ var _ = framework.IngressNginxDescribe("[Service] Type ExternalName", func() {
 		assert.Nil(ginkgo.GinkgoT(), err)
 		assert.Contains(ginkgo.GinkgoT(), output, `{"address":"eu.httpbin.org"`)
 	})
+
+	ginkgo.It("should sync ingress on external name service addition/deletion", func() {
+		host := "echo"
+
+		// Create the Ingress first
+		ing := framework.NewSingleIngress(host, "/", host, f.Namespace, framework.HTTPBinService, 80, nil)
+		ing.Spec.Rules[0].HTTP.Paths[0].Backend.ServicePort = intstr.FromString(host)
+		f.EnsureIngress(ing)
+
+		f.WaitForNginxServer(host,
+			func(server string) bool {
+				return strings.Contains(server, "proxy_pass http://upstream_balancer;")
+			})
+
+		// Nginx should return 503 without the underlying service being available
+		f.HTTPTestClient().
+			GET("/get").
+			WithHeader("Host", host).
+			Expect().
+			Status(http.StatusServiceUnavailable)
+
+		// Now create the service
+		svc := buildHTTPBinExternalNameService(f, host)
+		f.EnsureService(svc)
+
+		framework.Sleep()
+
+		// 503 should change to 200 OK
+		f.HTTPTestClient().
+			GET("/get").
+			WithHeader("Host", host).
+			Expect().
+			Status(http.StatusOK)
+
+		// And back to 503 after deleting the service
+
+		err := f.KubeClientSet.CoreV1().Services(f.Namespace).Delete(context.TODO(), framework.HTTPBinService, metav1.DeleteOptions{})
+		assert.Nil(ginkgo.GinkgoT(), err, "unexpected error deleting httpbin service")
+
+		framework.Sleep()
+
+		f.HTTPTestClient().
+			GET("/get").
+			WithHeader("Host", host).
+			Expect().
+			Status(http.StatusServiceUnavailable)
+	})
 })