Fix to inject KUBERNETES_ env vars when enableServiceLinks is

pkg/kubelet/kubelet_pods.go

@@ -514,24 +514,14 @@ func (kl *Kubelet) getServiceEnvVarMap(ns string, enableServiceLinks *bool) (map
 		}
 		serviceName := service.Name
 
-		switch service.Namespace {
 		// for the case whether the master service namespace is the namespace the pod
 		// is in, the pod should receive all the services in the namespace.
-		//
-		// ordering of the case clauses below enforces this
-		case ns:
-			// If service links are not enabled, we shouldn't add services from
-			// the same namespace.
-			if !*enableServiceLinks {
-				continue
+		if service.Namespace == kl.masterServiceNamespace && masterServices.Has(serviceName) {
+			if _, exists := serviceMap[serviceName]; !exists {
+				serviceMap[serviceName] = service
 			}
+		} else if service.Namespace == ns && *enableServiceLinks {
 			serviceMap[serviceName] = service
-		case kl.masterServiceNamespace:
-			if masterServices.Has(serviceName) {
-				if _, exists := serviceMap[serviceName]; !exists {
-					serviceMap[serviceName] = service
-				}
-			}
 		}
 	}
 

pkg/kubelet/kubelet_pods_test.go

@@ -36,6 +36,7 @@ import (
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	core "k8s.io/client-go/testing"
 	"k8s.io/client-go/tools/record"
+
 	// TODO: remove this import if
 	// api.Registry.GroupOrDie(v1.GroupName).GroupVersions[0].String() is changed
 	// to "v1"?
@@ -625,7 +626,15 @@ func TestMakeEnvironmentVariables(t *testing.T) {
 			container:          &v1.Container{},
 			masterServiceNs:    "kubernetes",
 			nilLister:          false,
-			expectedEnvs:       nil,
+			expectedEnvs: []kubecontainer.EnvVar{
+				{Name: "KUBERNETES_SERVICE_HOST", Value: "1.2.3.6"},
+				{Name: "KUBERNETES_SERVICE_PORT", Value: "8086"},
+				{Name: "KUBERNETES_PORT", Value: "tcp://1.2.3.6:8086"},
+				{Name: "KUBERNETES_PORT_8086_TCP", Value: "tcp://1.2.3.6:8086"},
+				{Name: "KUBERNETES_PORT_8086_TCP_PROTO", Value: "tcp"},
+				{Name: "KUBERNETES_PORT_8086_TCP_PORT", Value: "8086"},
+				{Name: "KUBERNETES_PORT_8086_TCP_ADDR", Value: "1.2.3.6"},
+			},
 		},
 		{
 			name:               "pod in master service ns, service env vars",