Revert "Drop support for --gce-service-account, require activated creds"

hack/ginkgo-e2e.sh

@@ -121,6 +121,7 @@ export PATH=$(dirname "${e2e_test}"):"${PATH}"
   --provider="${KUBERNETES_PROVIDER}" \
   --gce-project="${PROJECT:-}" \
   --gce-zone="${ZONE:-}" \
+  --gce-service-account="${GCE_SERVICE_ACCOUNT:-}" \
   --gke-cluster="${CLUSTER_NAME:-}" \
   --kube-master="${KUBE_MASTER:-}" \
   --cluster-tag="${CLUSTER_ID:-}" \

hack/jenkins/e2e-runner.sh

@@ -226,6 +226,7 @@ fi
 if [[ -f "${KUBEKINS_SERVICE_ACCOUNT_FILE:-}" ]]; then
   echo 'Activating service account...'  # No harm in doing this multiple times.
   gcloud auth activate-service-account --key-file="${KUBEKINS_SERVICE_ACCOUNT_FILE}"
+  unset GCE_SERVICE_ACCOUNT  # Use checked in credentials, not the metadata server
   unset KUBEKINS_SERVICE_ACCOUNT_FILE
 elif [[ -n "${KUBEKINS_SERVICE_ACCOUNT_FILE:-}" ]]; then
   echo "ERROR: cannot access service account file at: ${KUBEKINS_SERVICE_ACCOUNT_FILE}"

test/e2e/e2e.go

@@ -29,6 +29,8 @@ import (
 	"github.com/onsi/ginkgo/config"
 	"github.com/onsi/ginkgo/reporters"
 	"github.com/onsi/gomega"
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/google"
 
 	"k8s.io/kubernetes/pkg/api"
 	gcecloud "k8s.io/kubernetes/pkg/cloudprovider/providers/gce"
@@ -59,13 +61,20 @@ func setupProviderConfig() error {
 	case "gce", "gke":
 		var err error
 		framework.Logf("Fetching cloud provider for %q\r\n", framework.TestContext.Provider)
+		var tokenSource oauth2.TokenSource
+		tokenSource = nil
+		if cloudConfig.ServiceAccount != "" {
+			// Use specified service account for auth
+			framework.Logf("Using service account %q as token source.", cloudConfig.ServiceAccount)
+			tokenSource = google.ComputeTokenSource(cloudConfig.ServiceAccount)
+		}
 		zone := framework.TestContext.CloudConfig.Zone
 		region, err := gcecloud.GetGCERegion(zone)
 		if err != nil {
 			return fmt.Errorf("error parsing GCE/GKE region from zone %q: %v", zone, err)
 		}
 		managedZones := []string{zone} // Only single-zone for now
-		cloudConfig.Provider, err = gcecloud.CreateGCECloud(framework.TestContext.CloudConfig.ProjectID, region, zone, managedZones, "" /* networkUrl */, nil /* nodeTags */, "" /* nodeInstancePerfix */, nil /* tokenSource */, false /* useMetadataServer */)
+		cloudConfig.Provider, err = gcecloud.CreateGCECloud(framework.TestContext.CloudConfig.ProjectID, region, zone, managedZones, "" /* networkUrl */, nil /* nodeTags */, "" /* nodeInstancePerfix */, tokenSource, false /* useMetadataServer */)
 		if err != nil {
 			return fmt.Errorf("Error building GCE/GKE provider: %v", err)
 		}

test/e2e/framework/test_context.go

@@ -80,6 +80,7 @@ type CloudConfig struct {
 	NodeInstanceGroup string
 	NumNodes          int
 	ClusterTag        string
+	ServiceAccount    string
 
 	Provider cloudprovider.Interface
 }
@@ -135,6 +136,7 @@ func RegisterClusterFlags() {
 	flag.StringVar(&cloudConfig.MasterName, "kube-master", "", "Name of the kubernetes master. Only required if provider is gce or gke")
 	flag.StringVar(&cloudConfig.ProjectID, "gce-project", "", "The GCE project being used, if applicable")
 	flag.StringVar(&cloudConfig.Zone, "gce-zone", "", "GCE zone being used, if applicable")
+	flag.StringVar(&cloudConfig.ServiceAccount, "gce-service-account", "", "GCE service account to use for GCE API calls, if applicable")
 	flag.StringVar(&cloudConfig.Cluster, "gke-cluster", "", "GKE name of cluster being used, if applicable")
 	flag.StringVar(&cloudConfig.NodeInstanceGroup, "node-instance-group", "", "Name of the managed instance group for nodes. Valid only for gce, gke or aws. If there is more than one group: comma separated list of groups.")
 	flag.IntVar(&cloudConfig.NumNodes, "num-nodes", -1, "Number of nodes in the cluster")