def pre_ack_process(self, message):
        """
        TriggerInstance from message is create prior to acknowledging the message. This
        gets us a way to not acknowledge messages.
        """
        trigger = message["trigger"]
        payload = message["payload"]

        # Accomodate for not being able to create a TrigegrInstance if a TriggerDB
        # is not found.
        trigger_instance = container_utils.create_trigger_instance(
            trigger,
            payload or {},
            date_utils.get_datetime_utc_now(),
            raise_on_no_trigger=True,
        )

        return self._compose_pre_ack_process_response(trigger_instance, message)

        TriggerInstance from message is create prior to acknowledging the message. This
        gets us a way to not acknowledge messages.
        
st2reactor/st2reactor/rules/worker.py