Shell script to find docker image descendants

docker_desc.sh

#!/bin/bash
parent_short_id=$1
parent_id=`docker inspect --format '{{.Id}}' $1`

get_kids() {
   local parent_id=$1
   docker inspect --format='ID {{.Id}} PAR {{.Parent}}' $(docker images -a -q) | grep "PAR ${parent_id}" | sed -E "s/ID ([^ ]*) PAR ([^ ]*)/\1/g"
}

print_kids() {
   local parent_id=$1
   local prefix=$2
   local tags=`docker inspect --format='{{.RepoTags}}' ${parent_id}`
   echo "${prefix}${parent_id} ${tags}"

   local children=`get_kids "${parent_id}"`

   for c in $children;
   do
       print_kids "$c" "$prefix  "
   done
}

print_kids "$parent_id" ""