gcp start stop tagged instance script for cost saving

gcp_stop_start_instance.md

#!/bin/bash
set -euo pipefail

start_stop() {
  while read name zone ; do
      echo "$name with $zone"
      gcloud compute instances $CMD $name --zone $zone &
  done < <(gcloud  compute instances list --filter='tags.items~^stoppable$' --format='value(NAME,ZONE)')
  wait
  gcloud compute instances list --filter=running
  echo "$CMD are done!"
}

CMD=$1
gcloud compute instances list --filter=running

read -p "Do you want to proceed?" yn
case $yn in
    [Yy]* ) start_stop;;
    [Nn]* ) exit;;
    * ) echo "Please answer yes or no.";;
esac