Script to delete exited containers and untagged/unused images from docker

gistfile1.sh

#!/bin/bash

set -o errexit

echo "Removing exited docker containers..."
docker ps -a -f status=exited -q | xargs -r docker rm -v

echo "Removing dangling images..."
docker images --no-trunc -q -f dangling=true | xargs -r docker rmi

echo "Removing unused docker images"
images=($(docker images --digests | tail -n +2 | awk '{ img_id=$1; if($2!="<none>")img_id=img_id":"$2; if($3!="<none>") img_id=img_id"@"$3; print img_id}'))
containers=($(docker ps -a | tail -n +2 | awk '{print $2}'))

containers_reg=" ${containers[*]} "
remove=()

for item in ${images[@]}; do
  if [[ ! $containers_reg =~ " $item " ]]; then
    remove+=($item)
  fi
done

remove_images=" ${remove[*]} "

echo ${remove_images} | xargs -r docker rmi
echo "Done"

@rafaelcapucho It is probably because the container was started without providing a tag, the check that this script does is simply concatenating all images with tags and removing the ones that are not shown by docker ps.
So if there is a container running the latest tag of an image without specifying its tag this script will not detect it as running and will try to remove the image.

Thanks a lot!
I improve the image id list by manage none tag and use digest
https://gist.github.com/Dufgui/72debe81068bf3ecd7d8