Fail public download script on API / json parsing errors

ci/get-public-download-for-generic-package.sh

@@ -5,5 +5,17 @@ set -eu
 package_name=$1
 
 package_id=$(curl -sSf --header "PRIVATE-TOKEN: ${GITLAB_PROJECT_TOKEN}" "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages?sort=desc&per_page=1" | jq ".[] | select(.version == \"${BUILD_VERSION}\") | .id")
+
+if [[ -z "${package_id}" ]]; then
+    >&2 echo "Error: No package id found"
+    exit 1
+fi
+
 package_file_id=$(curl -sSf --header "PRIVATE-TOKEN: ${GITLAB_PROJECT_TOKEN}" "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/${package_id}/package_files" | jq ".[] | select(.file_name == \"$package_name\") | .id")
+
+if [[ -z "${package_file_id}" ]]; then
+    >&2 echo "Error: No package file id found"
+    exit 1
+fi
+
 echo "https://gitlab.archlinux.org/archlinux/archlinux-docker/-/package_files/${package_file_id}/download"