SqlAlchemy: Attaching one model to another during a "before_insert" event -


i'm having problems connecting subordinate model parent model using event handler. subordinate model never saved sqlalchemy (possibly because added during flush). i'm trying figure out how make work. places kind of thing happen scattered thru code , want catch of them. i've worked around set event, can see other places might want use code set event not acceptable.

def assure_subordinate(mapper, connect, target):     """ if try use address parent not have subordinate object            connected, create 1 , attach address. """     if not (target.address.subordinate or parent.address.subordinate_id):         address = target.address         session = inspect(address).session          sub = subordinate(account_id=target.account_id,                           name=address.name,                           email=address.email)         address.subordinate = sub         session.add(sub)  event.listen(parent, 'before_insert', assure_subordinate, propagate=true) event.listen(parent, 'before_update', assure_subordinate, propagate=true)

i'm hoping simple, otherwise before_insert events going terribly limited.


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