Question

我正在尝试建立一个拍卖网站，并且我有一个ForeignKey字段，如果可能的话，我可能想添加一些额外的参数。

现在，当我进入/ admin并进入“列表”并单击列表时，有一个用于Winners的下拉选择器。但是下拉选择器向我显示了所有已放置的出价，包括放置在其他列表上的出价。我如何获得下拉选择器，以便仅允许我从对特定列表进行了出价的用户中进行选择。我假设我需要在获奖者字段中添加某种条件？

models.py

class Listing(models.Model):

    class NewManager(models.Manager):
        def get_queryset(self):
            return super().get_queryset().filter(status='active')

    options = (
        ('active', 'Active'),
        ('closed', 'Closed'),
    )

    title = models.CharField(max_length=64)
    description = models.TextField(max_length=64)
    start_price = models.DecimalField(max_digits=9, decimal_places=2, validators=[MinValueValidator(0.99)])
    image = models.URLField(max_length=200, blank=True)
    category = models.ForeignKey(Category, on_delete=models.CASCADE, related_name="listings")
    lister = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, default=None, null=True, blank=True, related_name="lister_user")
    date_added = models.DateTimeField(default=timezone.now)
    status = models.CharField(max_length=10, choices=options, default="active")
    winner = models.ForeignKey('Bid', on_delete=models.CASCADE, null=True, related_name="bid_winner")
    favourites = models.ManyToManyField(User, related_name="favourite", default=None, blank=True)
    objects = models.Manager()
    listingmanager = NewManager()

    def __str__(self): 
        return f"{self.title} ({self.pk}, £{self.start_price}, {self.lister})"



class Bid(models.Model):
    bidder = models.ForeignKey(User, on_delete=models.CASCADE, related_name="bidders")
    bid_item = models.ForeignKey(Listing, on_delete=models.CASCADE, related_name="bid_items", default=None)
    bid_input = models.DecimalField(max_digits=9, decimal_places=2, default=None)
    time = models.DateTimeField(default=timezone.now)

    def __str__(self):
        return f"{self.bidder}, bid amount: {self.bid_input}"

我不确定是否需要 forms.py ，但会以防万一。一个单独的问题，但希望有人可以提供帮助。如果出价输入低于标价或最高出价，则下面的BidForm表单验证不会引发验证错误。谁能看到我在哪里出问题了？

class NewListingForm(forms.ModelForm):
    class Meta:
        model = Listing
        fields = ["title", "description", "start_price", "image", "category"]

    title = forms.CharField(widget=forms.TextInput(attrs={'autocomplete':'off'}))
    description = forms.CharField(widget=forms.TextInput(attrs={'autocomplete':'off'}))
    start_price = forms.DecimalField(label='Starting Bid Price (£)')
    image = forms.URLField(widget=forms.URLInput(attrs={'autocomplete':'off'}))
    category = forms.ModelChoiceField(queryset=Category.objects.all())



class BidForm(forms.ModelForm):
    class Meta:
        model = Bid
        fields = ["bid_input"]
        labels = {"bid_input": ""}
        widgets = {
            "bid_input": forms.NumberInput(attrs={'placeholder': 'Enter bid (£)'})
        }
    
    def clean_bid_input(self):
        input_bid = self.cleaned_data['bid_input']
        item_bid = self.cleaned_data['bid_item']
        highest_bid = Bid.objects.filter(item_bid).aggregate(Max('bid_input'))
        listing_price = Listing.objects.get('bid_item').start_price
        if highest_bid is None:
            if input_bid < listing_price:
                raise ValidationError('Bid must be higher than listing start price')
        else:
            if input_bid < highest_bid:
                raise ValidationError('Bid must be higher than current highest bid')
        return input_bid

将参数添加到ForeignKey字段？

0 个答案: