Django 继承模型："Cannot resolve keyword 'keyword' into field." (Django 2.1.1)

Question

伙计们。相同的上下文处理器，新问题（链接到）。

我有以下模型来检查网站上的促销活动：

class PagePromotion(LinkedPromotion):
   """
   A promotion embedded on a particular page.
   """
   page_url = URLField(max_length=128, min_length=0)

   def __str__(self):
       return "%s on %s" % (self.content_object, self.page_url)

   def get_link(self):
       return reverse('promotions:page-click',
                   kwargs={'page_promotion_id': self.id})

   class Meta(LinkedPromotion.Meta):
       verbose_name = _("Page Promotion")
       verbose_name_plural = _("Page Promotions")

继承自该模型：

class LinkedPromotion(models.Model):

# We use generic foreign key to link to a promotion model
content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
object_id = models.PositiveIntegerField()
content_object = fields.GenericForeignKey('content_type', 'object_id')

position = models.CharField(_("Position"), max_length=100,
                            help_text="Position on page")
display_order = models.PositiveIntegerField(_("Display Order"), default=0)
clicks = models.PositiveIntegerField(_("Clicks"), default=0)
date_created = models.DateTimeField(_("Date Created"), auto_now_add=True)

class Meta:
    abstract = True
    app_label = 'promotions'
    ordering = ['-clicks']
    verbose_name = _("Linked Promotion")
    verbose_name_plural = _("Linked Promotions")

def record_click(self):
    self.clicks += 1
    self.save()
record_click.alters_data = True

在与此页面相关的上下文处理器上，我编写了一段代码来请求这样的页面升级：

def get_request_promotions(request):
"""
Return promotions relevant to this request
"""

promotions = PagePromotion.objects.filter(page_url=request.path).order_by('display_order')

if 'q' in request.GET:
    keyword_promotions \
        = KeywordPromotion.objects.select_related().filter(keyword=request.GET['q'])
    if keyword_promotions.exists():
        promotions = list(chain(promotions, keyword_promotions))
return promotions

起初它就像链接版本，但由于出现以下错误，我尝试修改它：

Cannot resolve keyword 'page_url' into field.
Choices are: clicks, content_object, content_type, content_type_id, 
date_created, display_order, id, object_id, position`

如果您转到上一个问题，您会发现代码之间的细微差别。问题似乎是 Django 没有识别与继承模型相关的字段，但我不明白为什么。有什么提示吗？

Answer 1

我还没有完全解决这个问题，但问题似乎出在 URLField 上。不知道Django是不是看不懂字段，我把字段改成CharField就解决了。我将在请求 URLField 的字段上插入一个验证器，但万一有人遇到类似问题，这是解决问题的一种方法。

Django 继承模型："Cannot resolve keyword 'keyword' into field." (Django 2.1.1)

Django Inherited Model: "Cannot resolve keyword 'keyword' into field." (Django 2.1.1)

django

model

django-queryset

inherited