Method _verify_canload

lib/sqlalchemy/orm/dependency.py:264–303

(self, state)

            )

    def _verify_canload(self, state):
        if self.prop.uselist and state is None:
            raise exc.FlushError(
                "Can't flush None value found in "
                "collection %s" % (self.prop,)
            )
        elif state is not None and not self.mapper._canload(
            state, allow_subtypes=not self.enable_typechecks
        ):
            if self.mapper._canload(state, allow_subtypes=True):
                raise exc.FlushError(
                    "Attempting to flush an item of type "
                    "%(x)s as a member of collection "
                    '"%(y)s". Expected an object of type '
                    "%(z)s or a polymorphic subclass of "
                    "this type. If %(x)s is a subclass of "
                    '%(z)s, configure mapper "%(zm)s" to '
                    "load this subtype polymorphically, or "
                    "set enable_typechecks=False to allow "
                    "any subtype to be accepted for flush. "
                    % {
                        "x": state.class_,
                        "y": self.prop,
                        "z": self.mapper.class_,
                        "zm": self.mapper,
                    }
                )
            else:
                raise exc.FlushError(
                    "Attempting to flush an item of type "
                    "%(x)s as a member of collection "
                    '"%(y)s". Expected an object of type '
                    "%(z)s or a polymorphic subclass of "
                    "this type."
                    % {
                        "x": state.class_,
                        "y": self.prop,
                        "z": self.mapper.class_,
                    }
                )

    def _synchronize(self, state, child, associationrow, clearkeys, uowcommit):
        raise NotImplementedError()