cleanup-registry.sh

#!/bin/sh
# helper for cleanup docker registry (based on api v2)
# by @allex_wang
# GistID: 3aab7875e033815227dd313a79465e18
# requires: [jq]
set -eu

scriptName=$(basename "$0")
REGISTRY=127.0.0.1:5000
REG_USER=

help() {
  cat <<-HELP
	${scriptName} [OPTIONS] -u=allex:passwd --registry=192.168.0.219:5000
	Cleanup docker registry remnants (Based on registry api v2)
	 Options:
	  -r | --registry       Registry endpoint service (default: $REGISTRY)
	  -u | --user           Registry auth user/passwd pairs (eg. allex:123456)
	  -h | --help           Display this help and exit
	HELP
}

die() {
  [ "${1-}" ] && echo >&2 "${1}"
  exit "${2-1}"
}

while [ $# -gt 0 ]; do
  OPT=$1
  [ "$OPT" = "--" ] && break
  [ "$OPT" = "${OPT#-*}" ] && {
    args+=("$OPT")
    shift
    continue
  }
  if [ "${OPT##=*}" = "$OPT" ]; then
    OPTARG="${2-}"
    if [ "${OPTARG##-*}" = "${OPTARG}" ]; then
      shift
    else
      OPTARG=
    fi
  else
    OPT=$(echo "$1" | awk -F= '{print $1}')
    OPTARG=$(echo "$1" | awk -F= '{print $2}')
  fi
  case $OPT in
  -h | --help)
    help
    exit
    ;;
  -r | --registry) REGISTRY=$OPTARG ;;
  -u | --user) REG_USER=$OPTARG ;;
  *)
    echo "ERROR: unknown parameter \"$OPT\""
    help
    exit 1
    ;;
  esac
  shift
done

# Registry
if [ -z "$REGISTRY" ]; then
  echo -n "Enter registry: "
  read -r REGISTRY
fi

# Registry User:Passwd
if [ -z "$REG_USER" ]; then
  read -rp "Enter authorization for registry ${REGISTRY}: " REG_USER
  [ -n "$REG_USER" ] || die "abort."
  if [ "${REG_USER#*:}" = "${REG_USER}" ]; then
    read -sp "Enter host password for user '$REG_USER': "
    [ -n "$REPLY" ] || die "abort."
    REG_USER=$REG_USER:$REPLY
  fi
fi

api() {
  a=$1
  shift
  curl --user "${REG_USER}" -s http://${REGISTRY}/v2/$a "$@"
}

c_id=$(docker ps | awk 'match($2, /registry:.*/) {print $1}')
[ -n "$c_id" ] || exit 1

del_reg_storage() {
  local target=$1
  echo "delete repository $target"
  docker exec -i "$c_id" rm -rf "/var/lib/registry/docker/registry/v2/repositories/$target"
}

cleanup_tag() {
  repo="$1"
  tag="$2"
  echo "=> check $repo:$tag..."
  digests="$(api "$repo/manifests/$tag" -H "Accept: application/vnd.docker.distribution.manifest.v2+json, application/vnd.oci.image.manifest.v1+json, application/vnd.docker.distribution.manifest.list.v2+json" | jq -r '.manifests[].digest' 2>/dev/null)"
  (
    set +e
    cat <<-EOF | (while read -r t; do (api "$repo/manifests/$t" | grep "MANIFEST_UNKNOWN") && exit 2; done)
			$digests
		EOF
    if [ $? -eq 2 ]; then
      cat <<-EOF | (while read -r t; do (api "$repo/manifests/$t" -X DELETE; del_reg_storage "$repo/_manifests/versions/${t/:\/}"); done)
				$digests
			EOF

      del_reg_storage "$repo/_manifests/tags/$tag"
      (exit 2)
    fi
  )
  return $?
}

# return false (with no-zero exit code) if repo tags not valid
check_tags() {
  local repo=$1
  if api $repo/tags/list | egrep '"tags":null|"NAME_UNKNOWN"' &>/dev/null; then
    return 1
  fi
  return 0
}

cleanup() {
  repositories=($(api "_catalog" | jq -r ".repositories|.[]"))
  for i in "${repositories[@]}"; do
    if ! check_tags $i; then
      del_reg_storage "$i"
    else (
      set +eE
      api $i/tags/list | jq -r ".tags|.[]" | (while read -a t; do (cleanup_tag "$i" "$t"); done)
      if ! check_tags $i; then
        del_reg_storage "$i"
      fi
    ); fi
  done
}

echo "cleanup registry..."
cleanup

echo "garbage-collect registry..."
docker exec "$c_id" registry garbage-collect /etc/docker/registry/config.yml &>/dev/null

echo "restart registry..."
docker restart $c_id &>/dev/null

echo "done!"