Acquire cluster admin role for only GKE (#1339)

* acquire cluster admin role for only GKE

* add comment

* address comments

* move command outside the if

scripts/e2e-tests.sh

@@ -323,10 +323,9 @@ function setup_test_cluster() {
     abort "kubeconfig context set to ${k8s_cluster}, which is forbidden"
 
   # If cluster admin role isn't set, this is a brand new cluster
-  # Setup the admin role and also KO_DOCKER_REPO
-  if [[ -z "$(kubectl get clusterrolebinding cluster-admin-binding 2> /dev/null)" ]]; then
+  # Setup the admin role and also KO_DOCKER_REPO if it is a GKE cluster
+  if [[ -z "$(kubectl get clusterrolebinding cluster-admin-binding 2> /dev/null)" && "${k8s_cluster}" =~ ^gke_.* ]]; then
     acquire_cluster_admin_role ${k8s_user} ${E2E_CLUSTER_NAME} ${E2E_CLUSTER_REGION} ${E2E_CLUSTER_ZONE}
-    kubectl config set-context ${k8s_cluster} --namespace=default
     # Incorporate an element of randomness to ensure that each run properly publishes images.
     export KO_DOCKER_REPO=gcr.io/${E2E_PROJECT_ID}/${E2E_BASE_NAME}-e2e-img/${RANDOM}
   fi
@@ -335,9 +334,12 @@ function setup_test_cluster() {
   is_protected_gcr ${KO_DOCKER_REPO} && \
     abort "\$KO_DOCKER_REPO set to ${KO_DOCKER_REPO}, which is forbidden"
 
-  echo "- Project is ${E2E_PROJECT_ID}"
+  # Use default namespace for all subsequent kubectl commands in this context
+  kubectl config set-context ${k8s_cluster} --namespace=default
+
+  echo "- gcloud project is ${E2E_PROJECT_ID}"
+  echo "- gcloud user is ${k8s_user}"
   echo "- Cluster is ${k8s_cluster}"
-  echo "- User is ${k8s_user}"
   echo "- Docker is ${KO_DOCKER_REPO}"
 
   export KO_DATA_PATH="${REPO_ROOT_DIR}/.git"