Django createview 创建没有外键的额外实例

Question

我正在使用 Django createview 在拍卖网站中创建投标项目。createview 将创建新对象，但它会创建一个没有相应外键的额外对象实例。我正在使用 @staticmethod 来确定提交的出价是否确实是最高出价，然后在相关列表中创建。如果您能指出我做错了什么，请提前致谢。

models.py

class Bid(TimeStampMixin):

    """model representing bid obj"""

    auction = models.ForeignKey(

        Listing, 

        on_delete=models.SET_NULL, 

        related_name='offer', 

        null=True)

    bidder = models.ForeignKey(

        settings.AUTH_USER_MODEL, 

        on_delete=models.SET_NULL, 

        null=True,

        related_name='bid_user')

    amount = models.PositiveIntegerField()

    objects = BidQuerySet.as_manager()

        

    def __str__(self):

        return f"{self.amount} in Listing No: {self.auction.id}"

    class Meta:

        ordering = ['amount']

    @staticmethod

    def high_bid(auction, bidder, bid_amount):

        """util method to ascertain highest bid in auction then create in related auction obj

        :param auction---listing being bid on, bid__auction

        :param bidder---user bidding

        :param amount--- current highest bid

        """

        ###error checks, is auction running? is current bid less than start bid? etc

        if bid_amount < auction.start_bid:

            return

        if (auction.highest_offer and bid_amount < auction.highest_offer.amount):

            return

        if bidder.id is auction.user.id:

            raise PermissionDenied

        ##after checks create highest bid object in listing model

        new_high_bid = Bid.objects.create(

            auction= auction,

            bidder = bidder,

            amount = bid_amount

        )

Answer 1

从 form_valid 中删除该return super().form_valid(form)行。这行代码将从继承类中调用 form_valid 来保存对象 - 这是在没有外键的情况下创建的额外对象。相反，您将希望返回某种 http 响应（例如 render_to_response、重定向等）。