Update all docker images, ignoring untagged images, and then remove dangling images

update_all_docker_images.sh

#!/bin/bash

# collect the list of docker images
images=$(docker images --format "{{.Repository}}:{{.Tag}}")

# iterate through each image
for image in $images
do
  if [[ $image != *"<none>"* ]]; then
    # the image is tagged, so pull the latest version
    echo "Pulling $image"
    docker pull $image
  else
    # the image isn't tagged (it's dangling), so skip it
    echo "Skipping $image"
  fi

  # output a visual indicator between each image processing
  echo =========================================================================
done

# removing dangling (untagged) images
docker rmi $(docker images --format "{{.ID}}" --filter "dangling=true")