One of the more tedious constant tasks in Openstack, especially if you’re using CI/CD, is to update images. Here’s a little script to make this just a little easier for you.

#!/bin/sh
asksure() {
echo -n "Are you sure (Y/N)? "
while read -r -n 1 -s answer; do
  if [[ $answer = [YyNn] ]]; then
    [[ $answer = [Yy] ]] && retval=0
    [[ $answer = [Nn] ]] && retval=1
    break
  fi
done

echo # just a final linefeed, optics...

return $retval
}
template=$(basename $1|sed s/.qcow2//ig)

filename=$1

images=$(glance image-list|grep $template|cut -f 3 -d '|'|sed s/\ /''/g)
guids=$(glance image-list|grep $template|cut -f 2 -d '|'|sed s/\ /''/g)

if [ ! -z $images ]; then
	echo images exist in glance
	echo $images
	echo "Image(s) will be deleted"
	if asksure; then
  	echo "Delete in progress ..."
		glance image-delete $guids
	else
  	exit 1
	fi

fi


echo creating image $filename for new template $template

glanceout=$(openstack image create \
	--disk-format qcow2 \
	--container-format bare \
	--public \
	--file $filename \
	$template)

id=$(glance image-list |grep $template|cut -f 2 -d '|'|sed s/\ //g)

glance image-update \
	--property hw_disk_bus=scsi \
	--property hw_cdrom_bus=ide \
	$id

NOTE: On some versions of Ubuntu, the Read command doesn’t work exactly as expected (I haven’t put the effort in to fine-tune this) so please debug this before using, and as always: Please be careful.