Clean up unused docker volumes, images and containers

docker_cleanup.sh

#!/usr/bin/env sh

is_root () { [ "$(id -u)" -eq 0 ]; }
is_docker_grp() { [ -n "$(id -Gn | grep docker)" ];  }

if ! is_root && ! is_docker_grp; then
  echo "You need to be 'root' or in the 'docker'-group!"
  echo "Try 'sudo docker_cleanup.sh'"
  exit 1
fi

# Remove exited containers
docker ps -a -q -f status=exited | xargs --no-run-if-empty docker rm -v

# Remove dangling images
docker images -f "dangling=true" -q | xargs --no-run-if-empty docker rmi

# Remove unused images (2 month up)
docker images | awk '/months ago/  { print $3}' | xargs --no-run-if-empty docker rmi

# Remove unused images (2 years up)
docker images | awk '/years ago/  { print $3}' | xargs --no-run-if-empty docker rmi

# Remove dangling volumes
docker volume ls -qf dangling=true | xargs --no-run-if-empty docker volume rm