engine.py 文件源码

def init(self, session, api):
        self.session = session
        self.api = api

        # compile queries
        self.command_queries = {}
        self.command_queries['character'] = \
            session.query(Command).\
            filter(Command.actor_id == bindparam('actor_id'))

        self.command_queries['children'] = \
            session.query(Actor, Command).\
            filter(Actor.id == bindparam('actor_id')).\
            join(Actor.parent, aliased=True).\
            filter(Command.actor_id == Actor.id)

        location = aliased(Actor)
        self.command_queries['location'] = \
            session.query(Command).\
            join(location).\
            join(Actor, location.id == Actor.parent_id).\
            filter(Actor.id == bindparam('actor_id'))

        location = aliased(Actor)
        children = aliased(Actor)
        self.command_queries['location_children'] = \
            session.query(Command).\
            join(children).\
            join(location, location.id == children.parent_id).\
            join(Actor, location.id == Actor.parent_id).\
            filter(Actor.id == bindparam('actor_id')).\
            filter(Command.actor_id == children.id)

        self.command_precedence = ['character', 'children', 'location', 'location_children']