查询扩展用户模型返回

Question

进行以下查询时，我收到一个错误：

Election.objects.all().exclude(candidate__UserID=request.user).filter(Gender=request.user.Profile.Gender).filter(CandidateReg=True)

对于此模型：

class Election(models.Model):
    Name = models.CharField(max_length=20)
    CandidateReg = models.BooleanField(default=True)
    VotingOpen = models.BooleanField(default=False)
    Description = models.CharField(max_length=255, null=True, blank=True)
    GENDERS = (("M","Male"), ("F","Female"))
    Gender = models.CharField(max_length=1, choices=GENDERS, default="M")
    Seats = models.IntegerField(default=7)
    FlipGrid = models.URLField(null=True, blank=True)
    Complete = models.BooleanField(default=False)

此错误中描述了该问题：

Traceback (most recent call last):
      File "/home/elections/venv/lib/python3.6/site-packages/django/core/handlers/exception.py", line 41, in inner
        response = get_response(request)
      File "/home/elections/venv/lib/python3.6/site-packages/django/core/handlers/base.py", line 187, in _get_response
        response = self.process_exception_by_middleware(e, request)
      File "/home/elections/venv/lib/python3.6/site-packages/django/core/handlers/base.py", line 185, in _get_response
        response = wrapped_callback(request, *callback_args, **callback_kwargs)
      File "/home/elections/elections-real/elections/views.py", line 139, in add_candidate
        elections = Election.objects.all().exclude(candidate__UserID=request.user).filter(Gender=request.user.Profile.Gender).filter(CandidateReg=True)
      File "/home/elections/venv/lib/python3.6/site-packages/django/utils/functional.py", line 239, in inner
        return func(self._wrapped, *args)
    AttributeError: 'User' object has no attribute 'Profile'

它似乎表明问题与当前用户配置文件中的Gender数据有关——这是用户模型的扩展。如下所示：

class Profile(models.Model):
    UserID = models.OneToOneField(User, on_delete=models.CASCADE)
    GENDERS = (("M","Male"), ("F","Female"))
    Gender = models.CharField(max_length=1, choices=GENDERS)
    UserTypeID = models.ForeignKey(UserType, on_delete=models.PROTECT, blank=True, null=True)
    EmailConfirmed = models.BooleanField(default=False)

@receiver(post_save, sender=User)
def create_user_profile(sender, instance, created, **kwargs):
    if created:
        Profile.objects.create(UserID=instance)

@receiver(post_save, sender=User)
def save_user_profile(sender, instance, **kwargs):
    instance.profile.save()

如果不是以上述方式，如何正确引用已登录用户配置文件的Gender属性

Answer 1

一对一字段的反向访问器始终是模型的小写名称：因此它应该是request.user.profile...

如果您遵循标准的PEP-8兼容样式，并使用小写形式命名所有字段-gender、voting_open、email_confirmed等，那么您就不会感到惊讶了。另外请注意，给关系字段命名以ID结尾并不是最佳做法，因为它们提供了对整个相关对象的访问，而不仅仅是ID，所以你的UserID应该叫做user

最后，关于性别，请阅读Falsehoods Programmers believe about Gender，并考虑你是否真的需要问这个信息。