在Django基于类视图中验证唯一性字段

Question

我需要排除表单中的'user'字段，因为'user'是将添加模型的loggedin用户。在阅读了所有Django表单文档并参考这里的答案后，Django's ModelForm unique_together validation

我的django views.py仍然报告错误，其中'user'是登录用户

Request Method: POST
Request URL:    http://localhost:8080/flavor/add_flavor/
Django Version: 1.8
Exception Type: KeyError
Exception Value: 'user'

谁能指出我代码中的错误?

models.py

class Flavor(models.Model):
    user = models.ForeignKey(UserProfile, related_name='flavors', verbose_name=_('user'))
    # Attributes
    name = models.CharField(max_length=100, verbose_name=_('name'), help_text=_('Enter the flavor name'))
    date_created = models.DateField(_("date created"), default=datetime.date.today)
    class Meta:
        verbose_name = _('Flavor')
        verbose_name_plural = _('Flavors')
        ordering = ('name', 'user')
        unique_together = ('user', 'name')

forms.py

class FlavorForm(forms.ModelForm):
    class Meta:
        model = Flavor
        # Never use exclude keyword which involves Massive Assignment Risk
        fields = ('name', 'date_created')
    def __init__(self, *args, **kwargs):
        # set the user as an attribute of the form which is more robust
        # Always pop user from kwargs before calling super()
        self.user = kwargs.pop('user')
        super(FlavorForm, self).__init__(*args, **kwargs)
    def clean(self):
        '''
        To verify the uniqueness by the unique_together fields
        '''
        cleaned_data = super(FlavorForm, self).clean()
        if Flavor.objects.filter(name=cleaned_data.get('name',''), user=self.user).exists():
            raise ValidationError(_('You have already added a flavor with this name'), code='invalid')
        # Always return cleaned data
        return cleaned_data

views.py

class FlavorCreateView(LoginRequiredMixin, CreateView):
    model = Flavor
    form_class = FlavorForm
    template_name = 'flavor/add_flavor.html'
    view_name = 'add_flavor'
    success_url = reverse_lazy(view_name)
    def get_form_kwargs(self):
        '''
        This injects form with keyword arguments.
        '''
        kwargs = super(FlavorCreateView, self).get_form_kwargs()
        #Update the kwargs with the user_id
        kwargs['user'] = self.request.user
        return kwargs

    def post(self, request, *args, **kwargs):
        form = self.form_class(request.POST)
        if form.is_valid():
            form.save()
            # process cleaned data
            return HttpResponseRedirect(success_url)
        return render(request, self.template_name, {'form': form})

Answer 1

您已经仔细定义了get_form_kwargs以提供用户kwarg。但是由于某种原因你重写了post;您的版本直接实例化表单，忽略helper方法。

很少有理由在cbv中重写post，当然不是在你的情况下。删除整个方法

(注意，这与检查唯一性无关)

Answer 2

我在FlavorForm中删除了post方法并覆盖了clean方法以保证唯一性。