#!/bin/bash

# Tags an already existing image version in a remote registry without needing to pull/push the whole image
# 
# Usage:
#  /bin/docker-remote-tag <repo-name> <existing-tag> <new-tag>
# 

REPOSITORY="$1"
TAG_OLD="$2"
TAG_NEW="$3"

CONTENT_TYPE="application/vnd.docker.distribution.manifest.v2+json"

MANIFEST=$(curl -H "Accept: ${CONTENT_TYPE}" "${DOCKER_REGISTRY}/v2/${REPOSITORY}/manifests/${TAG_OLD}")

curl -X PUT -H "Content-Type: ${CONTENT_TYPE}" -d "${MANIFEST}" "${DOCKER_REGISTRY}/v2/${REPOSITORY}/manifests/${TAG_NEW}"