Flask-SQLAlchemy models_committed信号出错

Question

我想在模型插入数据库后进行一些数据库操作。所以我为此做了一个钩子：

@models_committed.connect
def on_models_committed(sender, changes):
    for obj, change in changes:
        if change == 'delete' and hasattr(obj, '__commit_delete__'):
            obj.__commit_delete__()
        elif change == 'insert' and hasattr(obj, '__commit_insert__'):
            obj.__commit_insert__()
        elif change == 'update' and hasattr(obj, '__commit_update__'):
            obj.__commit_update__()

在模特中我有：

def __commit_insert__(self):
    result = Model.query.filter(...).one()

执行此代码时，会发生以下错误：

sqlalchemy.exc.InvalidRequestError: This session is in 'committed' state; no further SQL can be emitted within this transaction.

如何避免这种情况？在__commit_insert__方法中，我需要插入记录的主键，因此对于本例，本机事件＆＃34; after_insert＆＃34;和＆＃34; after_flush＆＃34; SQLAlchemy不适合