'Return a zaqar queue_id for signaling this resource.
This uses the created user for the credentials.'

def _get_zaqar_signal_queue_id(self):

    queue_id = self.data().get('zaqar_signal_queue_id')
    if queue_id:
        return queue_id
    if (self.id is None):
        return
    if (self._get_user_id() is None):
        if (self.password is None):
            self.password = uuid.uuid4().hex
        self._create_user()
    queue_id = self.physical_resource_name()
    zaqar_plugin = self.client_plugin('zaqar')
    zaqar = zaqar_plugin.create_for_tenant(self.stack.stack_user_project_id, self._user_token())
    queue = zaqar.queue(queue_id)
    signed_url_data = queue.signed_url(['messages'], methods=['GET', 'DELETE'])
    self.data_set('zaqar_queue_signed_url_data', jsonutils.dumps(signed_url_data))
    self.data_set('zaqar_signal_queue_id', queue_id)
    return queue_id
