Merge pull request #3938 from johngmyers/internal-service

Use ServiceIP for ClusterIP Services with internal-hostname annotation
kubernetes-sigs · Sep 26, 2023 · 9ad15cf · 9ad15cf
2 parents 8251b6d + 7044fdf
commit 9ad15cf
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Showing 4 changed files with 35 additions and 16 deletions.
diff --git a/docs/annotations/annotations.md b/docs/annotations/annotations.md
@@ -25,7 +25,7 @@ The following table documents which sources support which annotations:
 | Traefik      |            | Yes      |                   | Yes     | Yes | Yes                 |
 
 [^1]: Unless the `--ignore-hostname-annotation` flag is specified.
-[^2]: Only behaves differently than `hostname` for `Service`s of type `LoadBalancer`.
+[^2]: Only behaves differently than `hostname` for `Service`s of type `ClusterIP` or `LoadBalancer`.
 [^3]: Also supported on `Pods` referenced from a headless `Service`'s `Endpoints`.
 [^4]: The annotation should be on the `Gateway`
 

diff --git a/docs/sources/service.md b/docs/sources/service.md
@@ -75,7 +75,8 @@ or the `--publish-host-ip` flag was specified, uses the Pod's `status.hostIP` fi
 
 ### ClusterIP (not headless)
 
-1. If the `--publish-internal-services` flag is specified, uses the `spec.ServiceIP`.
+1. If the hostname came from an `external-dns.alpha.kubernetes.io/internal-hostname` annotation
+or the `--publish-internal-services` flag was specified, uses the `spec.ServiceIP`.
 
 2. Otherwise, does not create any targets.
 

diff --git a/source/service.go b/source/service.go
@@ -505,7 +505,7 @@ func (sc *serviceSource) generateEndpoints(svc *v1.Service, hostname string, pro
 		case v1.ServiceTypeClusterIP:
 			if svc.Spec.ClusterIP == v1.ClusterIPNone {
 				endpoints = append(endpoints, sc.extractHeadlessEndpoints(svc, hostname, ttl)...)
-			} else if sc.publishInternal {
+			} else if useClusterIP || sc.publishInternal {
 				targets = extractServiceIps(svc)
 			}
 		case v1.ServiceTypeNodePort:

diff --git a/source/service_test.go b/source/service_test.go
@@ -910,7 +910,25 @@ func testServiceSourceEndpoints(t *testing.T) {
 			expected:           []*endpoint.Endpoint{},
 		},
 		{
-			title:        "internal-host annotated services return an endpoint with Cluster IP",
+			title:        "internal-host annotated and host annotated clusterip services return an endpoint with Cluster IP",
+			svcNamespace: "testing",
+			svcName:      "foo",
+			svcType:      v1.ServiceTypeClusterIP,
+			labels:       map[string]string{},
+			annotations: map[string]string{
+				hostnameAnnotationKey:         "foo.example.org.",
+				internalHostnameAnnotationKey: "foo.internal.example.org.",
+			},
+			clusterIP:          "1.1.1.1",
+			externalIPs:        []string{},
+			lbs:                []string{"1.2.3.4"},
+			serviceTypesFilter: []string{},
+			expected: []*endpoint.Endpoint{
+				{DNSName: "foo.internal.example.org", RecordType: endpoint.RecordTypeA, Targets: endpoint.Targets{"1.1.1.1"}},
+			},
+		},
+		{
+			title:        "internal-host annotated loadbalancer services return an endpoint with Cluster IP",
 			svcNamespace: "testing",
 			svcName:      "foo",
 			svcType:      v1.ServiceTypeLoadBalancer,
@@ -927,7 +945,7 @@ func testServiceSourceEndpoints(t *testing.T) {
 			},
 		},
 		{
-			title:        "internal-host annotated and host annotated services return an endpoint with Cluster IP and an endpoint with lb IP",
+			title:        "internal-host annotated and host annotated loadbalancer services return an endpoint with Cluster IP and an endpoint with lb IP",
 			svcNamespace: "testing",
 			svcName:      "foo",
 			svcType:      v1.ServiceTypeLoadBalancer,
@@ -1816,10 +1834,10 @@ func TestServiceSourceNodePortServices(t *testing.T) {
 					},
 				},
 			}},
-			podNames:  []string{"pod-0"},
-			nodeIndex: []int{1},
-			phases:    []v1.PodPhase{v1.PodRunning},
-			conditions: []v1.PodCondition{{Type: v1.PodReady, Status: v1.ConditionFalse}},
+			podNames:          []string{"pod-0"},
+			nodeIndex:         []int{1},
+			phases:            []v1.PodPhase{v1.PodRunning},
+			conditions:        []v1.PodCondition{{Type: v1.PodReady, Status: v1.ConditionFalse}},
 			deletionTimestamp: []*metav1.Time{{}},
 		},
 		{
@@ -1867,7 +1885,7 @@ func TestServiceSourceNodePortServices(t *testing.T) {
 				{Type: v1.PodReady, Status: v1.ConditionFalse},
 				{Type: v1.PodReady, Status: v1.ConditionFalse},
 			},
-			deletionTimestamp: []*metav1.Time{{},{}},
+			deletionTimestamp: []*metav1.Time{{}, {}},
 		},
 		{
 			title:            "annotated NodePort services with ExternalTrafficPolicy=Local return pods in Ready & Running state",
@@ -1911,7 +1929,7 @@ func TestServiceSourceNodePortServices(t *testing.T) {
 				{Type: v1.PodReady, Status: v1.ConditionTrue},
 				{Type: v1.PodReady, Status: v1.ConditionFalse},
 			},
-			deletionTimestamp: []*metav1.Time{{},{}},
+			deletionTimestamp: []*metav1.Time{{}, {}},
 		},
 		{
 			title:            "annotated NodePort services with ExternalTrafficPolicy=Local return pods in Ready & Running state & not in Terminating",
@@ -2254,14 +2272,14 @@ func TestServiceSourceNodePortServices(t *testing.T) {
 						NodeName:   tc.nodes[tc.nodeIndex[i]].Name,
 					},
 					ObjectMeta: metav1.ObjectMeta{
-						Namespace:   tc.svcNamespace,
-						Name:        podname,
-						Labels:      tc.labels,
-						Annotations: tc.annotations,
+						Namespace:         tc.svcNamespace,
+						Name:              podname,
+						Labels:            tc.labels,
+						Annotations:       tc.annotations,
 						DeletionTimestamp: tc.deletionTimestamp[i],
 					},
 					Status: v1.PodStatus{
-						Phase: tc.phases[i],
+						Phase:      tc.phases[i],
 						Conditions: []v1.PodCondition{tc.conditions[i]},
 					},
 				}