Merge pull request #59572 from ipuustin/shell-bugfix2

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Fix various bash scripts to make them more robust and uniform

**What this PR does / why we need it**:

The shellcheck tool (https://github.com/koalaman/shellcheck) finds a bunch of issues in kubernetes bash scripts. I started fixing the issues to make the scripts more robust and correct. This PR fixes some "low-hanging fruit" and also cleans up file `hack/update-godep-licenses.sh` in a more complete fashion.

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

cluster/gce/gci/flexvolume_node_setup.sh

@@ -81,10 +81,10 @@ flex_clean() {
   umount_silent ${MOUNTER_PATH}
   rm -rf ${MOUNTER_PATH}
   
-  if [ -n ${IMAGE_URL:-} ]; then
+  if [[ -n ${IMAGE_URL:-} ]]; then
     docker rmi -f ${IMAGE_URL} &> /dev/null || /bin/true
   fi
-  if [ -n ${MOUNTER_DEFAULT_NAME:-} ]; then
+  if [[ -n ${MOUNTER_DEFAULT_NAME:-} ]]; then
     docker rm -f ${MOUNTER_DEFAULT_NAME} &> /dev/null || /bin/true
   fi
 }

cluster/gce/list-resources.sh

@@ -57,7 +57,7 @@ function gcloud-compute-list() {
     fi
     echo -e "Attempt ${attempt} failed to list ${resource}. Retrying." >&2
     attempt=$(($attempt+1))
-    if [[ ${attempt} > 5 ]]; then
+    if [[ ${attempt} -gt 5 ]]; then
       echo -e "List ${resource} failed!" >&2
       exit 2
     fi

cluster/gce/upgrade-aliases.sh

@@ -53,7 +53,7 @@ function detect-k8s-subnetwork() {
   local subnetwork_url=$(gcloud compute instances describe \
     ${KUBE_MASTER} --project=${PROJECT} --zone=${ZONE} \
     --format='value(networkInterfaces[0].subnetwork)')
-  if [ -n ${subnetwork_url} ]; then
+  if [[ -n ${subnetwork_url} ]]; then
     IP_ALIAS_SUBNETWORK=$(echo ${subnetwork_url##*/})
   fi
 }

hack/update-godep-licenses.sh

@@ -74,10 +74,10 @@ process_content () {
   # Start search at package root
   case ${package} in
     github.com/*|golang.org/*|bitbucket.org/*)
-     package_root=$(echo ${package} |awk -F/ '{ print $1"/"$2"/"$3 }')
+     package_root=$(echo "${package}" |awk -F/ '{ print $1"/"$2"/"$3 }')
      ;;
     go4.org/*)
-     package_root=$(echo ${package} |awk -F/ '{ print $1 }')
+     package_root=$(echo "${package}" |awk -F/ '{ print $1 }')
      ;;
     gopkg.in/*)
      # Root of gopkg.in package always ends with '.v(number)' and my contain
@@ -85,10 +85,10 @@ process_content () {
      # - gopkg.in/yaml.v2
      # - gopkg.in/inf.v0
      # - gopkg.in/square/go-jose.v2
-     package_root=$(echo ${package} |grep -oh '.*\.v[0-9]')
+     package_root=$(echo "${package}" |grep -oh '.*\.v[0-9]')
      ;;
     *)
-     package_root=$(echo ${package} |awk -F/ '{ print $1"/"$2 }')
+     package_root=$(echo "${package}" |awk -F/ '{ print $1"/"$2 }')
      ;;
   esac
 
@@ -98,7 +98,7 @@ process_content () {
       [[ -d ${DEPS_DIR}/${dir_root} ]] || continue
 
       # One (set) of these is fine
-      find ${DEPS_DIR}/${dir_root} \
+      find "${DEPS_DIR}/${dir_root}" \
           -xdev -follow -maxdepth ${find_maxdepth} \
           -type f "${find_names[@]}"
     done | sort -u))
@@ -107,9 +107,14 @@ process_content () {
   local f
   index="${package}-${type}"
   if [[ -z "${CONTENT[${index}]-}" ]]; then
-    for f in ${local_files[@]-}; do
+    for f in "${local_files[@]-}"; do
+      if [[ -z "$f" ]]; then
+        # Set the default value and then check it to prevent
+        # accessing potentially empty array
+        continue
+      fi
       # Find some copyright info in any file and break
-      if egrep -i -wq "${ensure_pattern}" "${f}"; then
+      if grep -E -i -wq "${ensure_pattern}" "${f}"; then
         CONTENT[${index}]="${f}"
         break
       fi
@@ -151,19 +156,17 @@ declare -Ag CONTENT
 echo "================================================================================"
 echo "= Kubernetes licensed under: ="
 echo
-cat ${LICENSE_ROOT}/LICENSE
+cat "${LICENSE_ROOT}/LICENSE"
 echo
-echo "= LICENSE $(cat ${LICENSE_ROOT}/LICENSE | md5sum | awk '{print $1}')"
+echo "= LICENSE $(cat "${LICENSE_ROOT}/LICENSE" | md5sum | awk '{print $1}')"
 echo "================================================================================"
 ) > ${TMP_LICENSE_FILE}
 
 # Loop through every package in Godeps.json
-for PACKAGE in $(cat Godeps/Godeps.json | \
-                 jq -r ".Deps[].ImportPath" | \
-                 sort -f); do
-  process_content ${PACKAGE} LICENSE
-  process_content ${PACKAGE} COPYRIGHT
-  process_content ${PACKAGE} COPYING
+for PACKAGE in $(jq -r ".Deps[].ImportPath" < Godeps/Godeps.json | sort -f); do
+  process_content "${PACKAGE}" LICENSE
+  process_content "${PACKAGE}" COPYRIGHT
+  process_content "${PACKAGE}" COPYING
 
   # display content
   echo
@@ -195,7 +198,7 @@ __EOF__
   cat "${file}"
 
   echo
-  echo "= ${file} $(cat ${file} | md5sum | awk '{print $1}')"
+  echo "= ${file} $(cat "${file}" | md5sum | awk '{print $1}')"
   echo "================================================================================"
   echo
 done >> ${TMP_LICENSE_FILE}

hack/verify-cli-conventions.sh

@@ -30,7 +30,7 @@ make -C "${KUBE_ROOT}" WHAT="${BINS[*]}"
 
 clicheck=$(kube::util::find-binary "clicheck")
 
-if ! output=`$clicheck 2>&1`
+if ! output=$($clicheck 2>&1)
 then
 	echo "$output"
 	echo

hack/verify-godeps.sh

@@ -65,7 +65,7 @@ _kubetmp="${_kubetmp}/kubernetes"
 # Do all our work in the new GOPATH
 export GOPATH="${_tmpdir}"
 
-pushd "${_kubetmp}" 2>&1 > /dev/null
+pushd "${_kubetmp}" > /dev/null 2>&1
   # Restore the Godeps into our temp directory
   hack/godep-restore.sh
 
@@ -78,11 +78,11 @@ pushd "${_kubetmp}" 2>&1 > /dev/null
 
   # Recreate the Godeps using the nice clean set we just downloaded
   hack/godep-save.sh
-popd 2>&1 > /dev/null
+popd > /dev/null 2>&1
 
 ret=0
 
-pushd "${KUBE_ROOT}" 2>&1 > /dev/null
+pushd "${KUBE_ROOT}" > /dev/null 2>&1
   # Test for diffs
   if ! _out="$(diff -Naupr --ignore-matching-lines='^\s*\"GoVersion\":' --ignore-matching-line='^\s*\"GodepVersion\":' --ignore-matching-lines='^\s*\"Comment\":' Godeps/Godeps.json ${_kubetmp}/Godeps/Godeps.json)"; then
     echo "Your Godeps.json is different:" >&2
@@ -117,9 +117,9 @@ pushd "${KUBE_ROOT}" 2>&1 > /dev/null
     fi
     ret=1
   fi
-popd 2>&1 > /dev/null
+popd > /dev/null 2>&1
 
-if [[ ${ret} > 0 ]]; then
+if [[ ${ret} -gt 0 ]]; then
   exit ${ret}
 fi
 

pkg/util/verify-util-pkg.sh

@@ -41,7 +41,7 @@ pushd "${BASH_DIR}" > /dev/null
   done
 popd > /dev/null
 
-if [[ ${ret} > 0 ]]; then
+if [[ ${ret} -gt 0 ]]; then
   exit ${ret}
 fi