dualstack endpoints integration tests

add integration tests to verify the behaviour of the endpoints
and endpointslices controller with dual stack services.

Since services can be single or dual stack, endpoints should be
generated for each IP family in the endpoint slice controller.

The legacy endpoint controller only will generate endpoints
in the first IP family configured in the service.

integration fix

Author: Antonio Ojea

test/integration/dualstack/BUILD

@@ -3,18 +3,23 @@ load("@io_bazel_rules_go//go:def.bzl", "go_test")
 go_test(
     name = "go_default_test",
     srcs = [
+        "dualstack_endpoints_test.go",
         "dualstack_test.go",
         "main_test.go",
     ],
     tags = ["integration"],
     deps = [
+        "//pkg/controller/endpoint:go_default_library",
+        "//pkg/controller/endpointslice:go_default_library",
         "//pkg/features:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",
+        "//staging/src/k8s.io/api/discovery/v1beta1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/api/errors:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/intstr:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
+        "//staging/src/k8s.io/client-go/informers:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
         "//staging/src/k8s.io/client-go/rest:go_default_library",
         "//staging/src/k8s.io/component-base/featuregate/testing:go_default_library",

test/integration/dualstack/dualstack_endpoints_test.go

@@ -0,0 +1,292 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package dualstack
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"testing"
+	"time"
+
+	v1 "k8s.io/api/core/v1"
+	discovery "k8s.io/api/discovery/v1beta1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/intstr"
+	"k8s.io/apimachinery/pkg/util/wait"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	"k8s.io/client-go/informers"
+	clientset "k8s.io/client-go/kubernetes"
+	restclient "k8s.io/client-go/rest"
+	featuregatetesting "k8s.io/component-base/featuregate/testing"
+	"k8s.io/kubernetes/pkg/controller/endpoint"
+	"k8s.io/kubernetes/pkg/controller/endpointslice"
+	"k8s.io/kubernetes/pkg/features"
+	"k8s.io/kubernetes/test/integration/framework"
+)
+
+func TestDualStackEndpoints(t *testing.T) {
+	// Create an IPv4IPv6 dual stack control-plane
+	serviceCIDR := "10.0.0.0/16"
+	secondaryServiceCIDR := "2001:db8:1::/48"
+	labelMap := func() map[string]string {
+		return map[string]string{"foo": "bar"}
+	}
+
+	dualStack := true
+	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.IPv6DualStack, dualStack)()
+
+	cfg := framework.NewIntegrationTestMasterConfig()
+	_, cidr, err := net.ParseCIDR(serviceCIDR)
+	if err != nil {
+		t.Fatalf("Bad cidr: %v", err)
+	}
+	cfg.ExtraConfig.ServiceIPRange = *cidr
+
+	_, secCidr, err := net.ParseCIDR(secondaryServiceCIDR)
+	if err != nil {
+		t.Fatalf("Bad cidr: %v", err)
+	}
+	cfg.ExtraConfig.SecondaryServiceIPRange = *secCidr
+
+	_, s, closeFn := framework.RunAMaster(cfg)
+	defer closeFn()
+
+	client := clientset.NewForConfigOrDie(&restclient.Config{Host: s.URL})
+
+	// Wait until the default "kubernetes" service is created.
+	if err = wait.Poll(250*time.Millisecond, time.Minute, func() (bool, error) {
+		_, err := client.CoreV1().Services(metav1.NamespaceDefault).Get(context.TODO(), "kubernetes", metav1.GetOptions{})
+		if err != nil && !apierrors.IsNotFound(err) {
+			return false, err
+		}
+		return !apierrors.IsNotFound(err), nil
+	}); err != nil {
+		t.Fatalf("Creating kubernetes service timed out")
+	}
+
+	resyncPeriod := 0 * time.Hour
+	informers := informers.NewSharedInformerFactory(client, resyncPeriod)
+
+	// Create fake node
+	testNode := &v1.Node{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "fakenode",
+		},
+		Spec: v1.NodeSpec{Unschedulable: false},
+		Status: v1.NodeStatus{
+			Conditions: []v1.NodeCondition{
+				{
+					Type:              v1.NodeReady,
+					Status:            v1.ConditionTrue,
+					Reason:            fmt.Sprintf("schedulable condition"),
+					LastHeartbeatTime: metav1.Time{Time: time.Now()},
+				},
+			},
+		},
+	}
+	if _, err := client.CoreV1().Nodes().Create(context.TODO(), testNode, metav1.CreateOptions{}); err != nil {
+		t.Fatalf("Failed to create Node %q: %v", testNode.Name, err)
+	}
+
+	epController := endpoint.NewEndpointController(
+		informers.Core().V1().Pods(),
+		informers.Core().V1().Services(),
+		informers.Core().V1().Endpoints(),
+		client,
+		1*time.Second)
+
+	epsController := endpointslice.NewController(
+		informers.Core().V1().Pods(),
+		informers.Core().V1().Services(),
+		informers.Core().V1().Nodes(),
+		informers.Discovery().V1beta1().EndpointSlices(),
+		int32(100),
+		client,
+		1*time.Second)
+
+	// Start informer and controllers
+	stopCh := make(chan struct{})
+	defer close(stopCh)
+	informers.Start(stopCh)
+	// use only one worker to serialize the updates
+	go epController.Run(1, stopCh)
+	go epsController.Run(1, stopCh)
+
+	var testcases = []struct {
+		name           string
+		serviceType    v1.ServiceType
+		ipFamilies     []v1.IPFamily
+		ipFamilyPolicy v1.IPFamilyPolicyType
+	}{
+		{
+			name:           "Service IPv4 Only",
+			serviceType:    v1.ServiceTypeClusterIP,
+			ipFamilies:     []v1.IPFamily{v1.IPv4Protocol},
+			ipFamilyPolicy: v1.IPFamilyPolicySingleStack,
+		},
+		{
+			name:           "Service IPv6 Only",
+			serviceType:    v1.ServiceTypeClusterIP,
+			ipFamilies:     []v1.IPFamily{v1.IPv6Protocol},
+			ipFamilyPolicy: v1.IPFamilyPolicySingleStack,
+		},
+		{
+			name:           "Service IPv6 IPv4 Dual Stack",
+			serviceType:    v1.ServiceTypeClusterIP,
+			ipFamilies:     []v1.IPFamily{v1.IPv6Protocol, v1.IPv4Protocol},
+			ipFamilyPolicy: v1.IPFamilyPolicyRequireDualStack,
+		},
+		{
+			name:           "Service IPv4 IPv6 Dual Stack",
+			serviceType:    v1.ServiceTypeClusterIP,
+			ipFamilies:     []v1.IPFamily{v1.IPv4Protocol, v1.IPv6Protocol},
+			ipFamilyPolicy: v1.IPFamilyPolicyRequireDualStack,
+		},
+	}
+
+	for i, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			ns := framework.CreateTestingNamespace(fmt.Sprintf("test-endpointslice-dualstack-%d", i), s, t)
+			defer framework.DeleteTestingNamespace(ns, s, t)
+
+			// Create a pod with labels
+			pod := &v1.Pod{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-pod",
+					Namespace: ns.Name,
+					Labels:    labelMap(),
+				},
+				Spec: v1.PodSpec{
+					NodeName: "fakenode",
+					Containers: []v1.Container{
+						{
+							Name:  "fake-name",
+							Image: "fakeimage",
+						},
+					},
+				},
+			}
+
+			createdPod, err := client.CoreV1().Pods(ns.Name).Create(context.TODO(), pod, metav1.CreateOptions{})
+			if err != nil {
+				t.Fatalf("Failed to create pod %s: %v", pod.Name, err)
+			}
+
+			// Set pod IPs
+			podIPbyFamily := map[v1.IPFamily]string{v1.IPv4Protocol: "1.1.1.1", v1.IPv6Protocol: "2001:db2::65"}
+			createdPod.Status = v1.PodStatus{
+				Phase:  v1.PodRunning,
+				PodIPs: []v1.PodIP{{IP: podIPbyFamily[v1.IPv4Protocol]}, {IP: podIPbyFamily[v1.IPv6Protocol]}},
+			}
+			_, err = client.CoreV1().Pods(ns.Name).UpdateStatus(context.TODO(), createdPod, metav1.UpdateOptions{})
+			if err != nil {
+				t.Fatalf("Failed to update status of pod %s: %v", pod.Name, err)
+			}
+
+			svc := &v1.Service{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      fmt.Sprintf("svc-test-%d", i), // use different services for each test
+					Namespace: ns.Name,
+					Labels:    labelMap(),
+				},
+				Spec: v1.ServiceSpec{
+					Type:           v1.ServiceTypeClusterIP,
+					IPFamilies:     tc.ipFamilies,
+					IPFamilyPolicy: &tc.ipFamilyPolicy,
+					Selector:       labelMap(),
+					Ports: []v1.ServicePort{
+						{
+							Name:       fmt.Sprintf("port-test-%d", i),
+							Port:       443,
+							TargetPort: intstr.IntOrString{IntVal: 443},
+							Protocol:   "TCP",
+						},
+					},
+				},
+			}
+
+			// create a service
+			_, err = client.CoreV1().Services(ns.Name).Create(context.TODO(), svc, metav1.CreateOptions{})
+			if err != nil {
+				t.Fatalf("Error creating service: %v", err)
+			}
+
+			// wait until endpoints are created
+			// legacy endpoints are not dual stack
+			// and use the address of the first IP family
+			if err := wait.PollImmediate(1*time.Second, wait.ForeverTestTimeout, func() (bool, error) {
+				e, err := client.CoreV1().Endpoints(ns.Name).Get(context.TODO(), svc.Name, metav1.GetOptions{})
+				if err != nil {
+					t.Logf("Error fetching endpoints: %v", err)
+					return false, nil
+				}
+				// check if the endpoint addresses match the pod IP of the first IPFamily of the service
+				// since this is an integration test PodIPs are not "ready"
+				if len(e.Subsets) > 0 && len(e.Subsets[0].NotReadyAddresses) > 0 {
+					if e.Subsets[0].NotReadyAddresses[0].IP == podIPbyFamily[tc.ipFamilies[0]] {
+						return true, nil
+					}
+					t.Logf("Endpoint address %s does not match PodIP %s ", e.Subsets[0].Addresses[0].IP, podIPbyFamily[tc.ipFamilies[0]])
+				}
+				t.Logf("Endpoint does not contain addresses: %s", e.Name)
+				return false, nil
+			}); err != nil {
+				t.Fatalf("Endpoints not found: %v", err)
+			}
+
+			// wait until the endpoint slices are created
+			err = wait.PollImmediate(1*time.Second, wait.ForeverTestTimeout, func() (bool, error) {
+				lSelector := discovery.LabelServiceName + "=" + svc.Name
+				esList, err := client.DiscoveryV1beta1().EndpointSlices(ns.Name).List(context.TODO(), metav1.ListOptions{LabelSelector: lSelector})
+				if err != nil {
+					t.Logf("Error listing EndpointSlices: %v", err)
+					return false, nil
+				}
+				// there must be an endpoint slice per ipFamily
+				if len(esList.Items) != len(tc.ipFamilies) {
+					t.Logf("Waiting for EndpointSlice to be created %v", esList)
+					return false, nil
+				}
+				// there must be an endpoint address per each IP family
+				for _, ipFamily := range tc.ipFamilies {
+					found := false
+					for _, slice := range esList.Items {
+						// check if the endpoint addresses match the pod IPs
+						if len(slice.Endpoints) > 0 && len(slice.Endpoints[0].Addresses) > 0 {
+							if string(ipFamily) == string(slice.AddressType) &&
+								slice.Endpoints[0].Addresses[0] == podIPbyFamily[ipFamily] {
+								found = true
+								break
+							}
+						}
+						t.Logf("Waiting endpoint slice to contain addresses")
+					}
+					if !found {
+						t.Logf("Endpoint slices does not contain PodIP %s", podIPbyFamily[ipFamily])
+						return false, nil
+					}
+				}
+				return true, nil
+			})
+			if err != nil {
+				t.Fatalf("Error waiting for endpoint slices: %v", err)
+			}
+		})
+	}
+}