Bash helper functions for mangling libvirt virtual machines

virt-helpers.sh

#!/usr/bin/env bash

# Check whether a named virtual machine exists.
#
# Arguments:
#   1: virtual machine name given by virsh
#
# Returns:
#   0 if virtual machine exists
#   1 if virtual machine does not exist
vm_exists() {
  virsh domstate $1 >/dev/null 2>&1
  return $?
}

# Check whether a named virtual machine is running.
#
# Arguments:
#   1: virtual machine name given by virsh
#
# Returns:
#   0 if virtual machine is running
#   1 if virtual machine is not running or does not exist
vm_is_running() {
  if [ "$(virsh domstate $1 2>/dev/null)" == "running" ]; then
    return 0
  else
    return 1
  fi
}

# Sleep until the given virtual machine is no longer running.
# Returns when the virtual machine is not running or does not exist.
#
# Arguments:
#   1: virtual machine name given by virsh
wait_for_vm_to_stop() {
  while vm_is_running $1; do
    sleep 1
  done
}

# Shut down a virtual machine through the normal shutdown signal. This
# results in a clean shutdown via the guest operating system.
#
# Arguments:
#   1: virtual machine name given by virsh
shutdown_vm() {
  if vm_is_running $1; then
    virsh shutdown $1
  fi
}

# Forcibly stop a virtual machine, even if it is not responding.
#
# Arguments:
#   1: virtual machine name given by virsh
force_stop_vm() {
  if vm_is_running $1; then
    virsh destroy $1
  fi
}

# Delete a virtual machine, all of its metadata, snapshots and storage.
# This should remove all traces of the VM.
#
# Arguments:
#   1: virtual machine name given by virsh
delete_vm() {
  force_stop_vm $1
  virsh undefine $1 --managed-save --snapshots-metadata --nvram --remove-all-storage
}