Allow authenticated Github use in changelog script and improve error messages

releasing/compile-changelog.sh

@@ -27,6 +27,13 @@ if [[ -z "${1-}" ]] || [[ -z "${2-}" ]]; then
   exit 1
 fi
 
+if [[ -z "${GITHUB_USERNAME-}" ]] || [[ -z "${GITHUB_TOKEN-}" ]]; then
+  echo "WARNING: Please set GITHUB_USERNAME and GITHUB_TOKEN to avoid GitHub API rate limits."
+  github_auth_string=""
+else
+  github_auth_string="-u ${GITHUB_USERNAME}:${GITHUB_TOKEN}"
+fi
+
 module=$1
 fullTag=$2
 changeLogFile="${3:-}"
@@ -49,10 +56,21 @@ results=""
 for((i=0; i < ${#commits[@]}; i+=batchSize))
 do
   commitList=$(IFS="+"; echo "${commits[@]:i:batchSize}" | sed 's/ /+/g')
-  if newResults=$(curl -sSL "https://api.github.com/search/issues?q=$commitList+repo%3Akubernetes-sigs%2Fkustomize" | jq -r '[  .items[] |  { number, title } ]'); then
+
+  if ! newResultsRaw=$(curl -sSL "https://api.github.com/search/issues?q=$commitList+repo%3Akubernetes-sigs%2Fkustomize+is:pull-request" "${github_auth_string}"); then
+    echo "Failed to fetch results for commits (exit code $?): $commitList"
+    exit 1
+  fi
+  if [[ "${newResultsRaw}" == *"API rate limit exceeded"* ]]; then
+    echo "GitHub API rate limit exceeded. Please set GITHUB_USERNAME and GITHUB_TOKEN to avoid this."
+    exit 1
+  fi
+
+  if [[ "${newResultsRaw}" == *"\"items\":"* ]] ; then
+    newResults=$(echo "$newResultsRaw" | jq -r '[  .items[] |  { number, title } ]')
     results=$(echo "$results" "$newResults" | jq -s '.[0] + .[1] | unique')
   else
-    echo "Failed to fetch results for commits (exit code $?): $commitList"
+    echo "Request for commits $commitList returned invalid results"
     exit 1
   fi
 done