Add cluster-location to GCE instance attributes

cluster/gce/gci/master-helper.sh

@@ -108,6 +108,7 @@ function create-master-instance-internal() {
   local metadata="kube-env=${KUBE_TEMP}/master-kube-env.yaml"
   metadata="${metadata},user-data=${KUBE_ROOT}/cluster/gce/gci/master.yaml"
   metadata="${metadata},configure-sh=${KUBE_ROOT}/cluster/gce/gci/configure.sh"
+  metadata="${metadata},cluster-location=${KUBE_TEMP}/cluster-location.txt"
   metadata="${metadata},cluster-name=${KUBE_TEMP}/cluster-name.txt"
   metadata="${metadata},gci-update-strategy=${KUBE_TEMP}/gci-update.txt"
   metadata="${metadata},gci-ensure-gke-docker=${KUBE_TEMP}/gci-ensure-gke-docker.txt"

cluster/gce/gci/node-helper.sh

@@ -22,6 +22,7 @@ function get-node-instance-metadata {
   metadata+="kube-env=${KUBE_TEMP}/node-kube-env.yaml,"
   metadata+="user-data=${KUBE_ROOT}/cluster/gce/gci/node.yaml,"
   metadata+="configure-sh=${KUBE_ROOT}/cluster/gce/gci/configure.sh,"
+  metadata+="cluster-location=${KUBE_TEMP}/cluster-location.txt,"
   metadata+="cluster-name=${KUBE_TEMP}/cluster-name.txt,"
   metadata+="gci-update-strategy=${KUBE_TEMP}/gci-update.txt,"
   metadata+="gci-ensure-gke-docker=${KUBE_TEMP}/gci-ensure-gke-docker.txt,"

cluster/gce/upgrade.sh

@@ -151,6 +151,7 @@ function prepare-upgrade() {
   detect-project
   detect-subnetworks
   detect-node-names # sets INSTANCE_GROUPS
+  write-cluster-location
   write-cluster-name
   tars_from_version
 }

cluster/gce/util.sh

@@ -472,6 +472,15 @@ function yaml-quote {
   echo "'$(echo "${@:-}" | sed -e "s/'/''/g")'"
 }
 
+# Writes the cluster location into a temporary file.
+# Assumed vars
+#   ZONE
+function write-cluster-location {
+  cat >"${KUBE_TEMP}/cluster-location.txt" << EOF
+${ZONE}
+EOF
+}
+
 # Writes the cluster name into a temporary file.
 # Assumed vars
 #   CLUSTER_NAME
@@ -1499,6 +1508,7 @@ function kube-up() {
     create-network
     create-subnetworks
     detect-subnetworks
+    write-cluster-location
     write-cluster-name
     create-autoscaler-config
     create-master