Augment script to update Kustomize if version is incorrect

Author: davidz627

deploy/kubernetes/install-kustomize.sh

@@ -9,15 +9,26 @@ set -o errexit
 
 readonly INSTALL_DIR="${GOPATH}/src/sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/bin"
 readonly KUSTOMIZE_PATH="${INSTALL_DIR}/kustomize"
+readonly KUSTOMIZE_VERSION="2.0.3"
+readonly VERSION_REGEX="KustomizeVersion:([0-9]\.[0-9]\.[0-9])"
+
+if [ -f "${KUSTOMIZE_PATH}" ]; then
+  if [[ $(${KUSTOMIZE_PATH} version) =~ ${VERSION_REGEX} ]]; then
+    if [ "${KUSTOMIZE_VERSION}" != "${BASH_REMATCH[1]}" ]; then
+      echo "Existing Kustomize version in ${KUSTOMIZE_PATH} v${BASH_REMATCH[1]}, need v${KUSTOMIZE_VERSION}. Removing existing binary."
+      rm "${KUSTOMIZE_PATH}"
+    fi
+  fi
+fi
 
 if [ ! -f "${KUSTOMIZE_PATH}" ]; then
   if [ ! -f "${INSTALL_DIR}" ]; then
     mkdir -p ${INSTALL_DIR}
   fi
 
-  echo "Installing kustomize in ${KUSTOMIZE_PATH}"
+  echo "Installing Kustomize v${KUSTOMIZE_VERSION} in ${KUSTOMIZE_PATH}"
   opsys=linux  # or darwin, or windows
-  curl -s https://api.github.com/repos/kubernetes-sigs/kustomize/releases/tags/v2.0.3 |\
+  curl -s https://api.github.com/repos/kubernetes-sigs/kustomize/releases/tags/v${KUSTOMIZE_VERSION} |\
     grep browser_download |\
     grep $opsys |\
     cut -d '"' -f 4 |\