tag docker image without downloading it (private gitlab registry)

tag_image_without_download.sh

AUTHURL="https://gitlab.de"
REGISTRY_NAME="https://reg.gitlab.de"
CONTENT_TYPE="application/vnd.docker.distribution.manifest.v2+json"

REPOSITORY="myrepo/ts1"
TAG_OLD="test"
TAG_NEW="latest"

USERNAME="test-tag-latest"
PASSWORD="sdfsdfdsfsdfsdf"

# Fetch JWT token
TOKEN=$(curl --silent --user ${USERNAME}:${PASSWORD} \
    -G ${AUTHURL}/jwt/auth \
    -d service=container_registry \
    -d scope="repository:${REPOSITORY}:push,pull,delete" \
    | jq -r '.token')
# oder
#TOKEN=$CI_JOB_TOKEN  #not tested but may work
BEARER="Authorization:Bearer $TOKEN"

MANIFEST=$(curl -H "$BEARER" -H "Accept: ${CONTENT_TYPE}" "${REGISTRY_NAME}/v2/${REPOSITORY}/manifests/${TAG_OLD}")
curl -X PUT -H "$BEARER" -H "Content-Type: ${CONTENT_TYPE}" -d "${MANIFEST}" "${REGISTRY_NAME}/v2/${REPOSITORY}/manifests/${TAG_NEW}"