added docker_registry_tag_image.sh

docker_registry_tag_image.sh

@@ -0,0 +1,66 @@
+#!/usr/bin/env bash
+#  vim:ts=4:sts=4:sw=4:et
+#  args: localhost:5000 centos haritest
+#
+#  Author: Hari Sekhon
+#  Date: 2020-09-30 12:05:41 +0100 (Wed, 30 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
+. "$srcdir/lib/utils.sh"
+
+# shellcheck disable=SC2034,SC2154
+usage_description="
+Tags a given image in a Docker Registry with another tag via the Docker Registry API v2
+without pulling and pushing the data (much faster and more efficient)
+
+If :<tag> isn't given, assumes 'latest'
+
+See adjacent docker_api.sh for authentication details
+"
+
+# used by usage() in lib/utils.sh
+# shellcheck disable=SC2034
+usage_args="http(s)://host:port <image>[:<tag>] <new_tag>"
+
+help_usage "$@"
+
+min_args 3 "$@"
+
+docker_registry_url="$1"
+image_tag="$2"
+new_tag="$3"
+shift || :
+shift || :
+shift || :
+
+if ! [[ "$docker_registry_url" =~ ^(https?://)?[[:alnum:].-]+:[[:digit:]]+/?$ ]]; then
+    usage "invalid docker registry url: $docker_registry_url"
+fi
+
+if ! [[ "$docker_registry_url" =~ ^https?:// ]]; then
+    docker_registry_url="http://$docker_registry_url"
+fi
+
+image="${image_tag%%:*}"
+tag="${image_tag##*:}"
+if ! [[ "$image_tag" =~ : ]] &&
+   [ "$tag" = "$image" ]; then
+    tag="latest"
+fi
+
+manifest="$("$srcdir/docker_registry_get_manifest.sh" "$docker_registry_url" "$image_tag" -H "Accept: application/vnd.docker.distribution.manifest.v2+json")"
+
+"$srcdir/docker_api.sh" "$docker_registry_url/v2/$image/manifests/$new_tag" -X PUT -d "$manifest" -H "Content-Type: application/vnd.docker.distribution.manifest.v2+json"