added gcr_list_tags_timestamps.sh

gcr_list_tags_timestamps.sh

@@ -0,0 +1,54 @@
+#!/usr/bin/env bash
+#  vim:ts=4:sts=4:sw=4:et
+#
+#  Author: Hari Sekhon
+#  Date: 2020-09-15 14:52:47 +0100 (Tue, 15 Sep 2020)
+#
+#  https://github.com/HariSekhon/bash-tools
+#
+#  License: see accompanying Hari Sekhon LICENSE file
+#
+#  If you're using my code you're welcome to connect with me on LinkedIn and optionally send me feedback to help steer this or other code I publish
+#
+#  https://www.linkedin.com/in/HariSekhon
+#
+
+set -euo pipefail
+[ -n "${DEBUG:-}" ] && set -x
+srcdir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# shellcheck disable=SC1090
+. "$srcdir/lib/utils.sh"
+
+# shellcheck disable=SC2034,SC2154
+usage_description="
+Lists all tags for the given Google Cloud Registry docker image as well as their image upload timestamp
+
+Output Format:
+
+<timestamp>   <tag>
+
+Each timestamp and tag for the given image is output tab separated on a separate line for easy further piping and filtering
+
+If the image isn't found in GCR, will return nothing and no error code since this is the default GCloud SDK behaviour
+
+Requires GCloud SDK to be installed and configured
+"
+
+# used by usage() in lib/utils.sh
+# shellcheck disable=SC2034
+usage_args="<gcr.io>/<project_id>/<image>:<tag>"
+
+help_usage "$@"
+
+num_args 1 "$@"
+
+image="$1"
+
+regex='^([^\.]+\.)?gcr\.io/[^/]+/[^:]+$'
+if ! [[ "$image" =~ $regex ]]; then
+    usage "unrecognized GCR image name - should be in a format matching this regex: $regex"
+fi
+
+gcloud container images list-tags "$image" --format=json |
+jq -r 'map(.timestamp.datetime + "\t" + .tags[]) | .[]'