e2e test for requiring memcached setting to configure global rate limit

test/e2e/admission/admission.go

@@ -45,6 +45,33 @@ var _ = framework.IngressNginxDescribe("[Serial] admission controller", func() {
 		assert.Nil(ginkgo.GinkgoT(), err, "uninstalling helm chart")
 	})
 
+	ginkgo.It("reject ingress with global-rate-limit annotations when memcached is not configured", func() {
+		host := "admission-test"
+
+		annotations := map[string]string{
+			"nginx.ingress.kubernetes.io/global-rate-limit":        "100",
+			"nginx.ingress.kubernetes.io/global-rate-limit-window": "1m",
+		}
+		ing := framework.NewSingleIngress("first-ingress", "/", host, f.Namespace, framework.EchoService, 80, annotations)
+
+		ginkgo.By("rejects ingress when memcached is not configured")
+
+		_, err := f.KubeClientSet.NetworkingV1beta1().Ingresses(f.Namespace).Create(context.TODO(), ing, metav1.CreateOptions{})
+		assert.NotNil(ginkgo.GinkgoT(), err, "creating ingress with global throttle annotations when memcached is not configured")
+
+		ginkgo.By("accepts ingress when memcached is not configured")
+
+		f.UpdateNginxConfigMapData("global-rate-limit-memcached-host", "memc.default.svc.cluster.local")
+
+		_, err = f.KubeClientSet.NetworkingV1beta1().Ingresses(f.Namespace).Create(context.TODO(), ing, metav1.CreateOptions{})
+		assert.Nil(ginkgo.GinkgoT(), err, "creating ingress with global throttle annotations when memcached is configured")
+
+		f.WaitForNginxServer(host,
+			func(server string) bool {
+				return strings.Contains(server, fmt.Sprintf("server_name %v", host))
+			})
+	})
+
 	ginkgo.It("should not allow overlaps of host and paths without canary annotations", func() {
 		host := "admission-test"