baseimage-tutorial-framework/tfw/components/fsm/fsm_updater.py

class FSMUpdater:
    def __init__(self, fsm):
        self.fsm = fsm

    @property
    def fsm_update(self):
        return {
            'key': 'fsm.update',
            **self.fsm_update_data
        }

    @property
    def fsm_update_data(self):
        valid_transitions = [
            {'trigger': trigger}
            for trigger in self.fsm.get_triggers(self.fsm.state)
        ]
        if not self.fsm.event_log:
            return None
        last_fsm_event = self.fsm.event_log[-1]
        return {
            'current_state': self.fsm.state,
            'valid_transitions': valid_transitions,
            'in_accepted_state': self.fsm.in_accepted_state,
            'last_event': last_fsm_event
        }