def publish_prompt(self, event=None):
        """
        Publishes prompt for a given event.

        Used to prompt downstream process application when an event
        is published by this application's model, which can happen
        when application command methods, rather than the process policy,
        are called.

        Wraps exceptions with PromptFailed, to avoid application policy exceptions being
        seen directly in other applications when running synchronously in single thread.
        """

        prompt = Prompt(self.name, self.pipeline_id)
        try:
            publish(prompt)
        except PromptFailed:
            raise
        except Exception as e:
            raise PromptFailed("{}: {}".format(type(e), str(e)))