python - create() 需要 1 个位置参数但给出了 2 个？

Question

我有一个名为 Following 的模型，它具有以下字段:

class Following(models.Model):
    target = models.ForeignKey('User', related_name='followers', on_delete=models.CASCADE)
    follower = models.ForeignKey('User', related_name='targets', on_delete=models.CASCADE)

    def __str__(self):
        return '{} is followed by {}'.format(self.target, self.follower)

我要创建的是一个关注按钮，按下该按钮后，目标就会成为关注者。在具有关注按钮的 View 中，具有以下逻辑:

class ProfileView(DetailView):
    model = User
    slug_field = 'username'
    template_name = 'oauth/profile.html'
    context_object_name = 'user_profile' # Without this, Django would default to request.user instead which is the logged in user

    def post(self, request, slug):
        follower = self.request.user

        self.object = self.get_object()
        context = self.get_context_data(object=self.object)

        follow_unfollow(follower, self.object.id)  # Error is found inside this function
        return render(request, self.template_name, context=context)

def follow_unfollow(follower, id):
    target = get_object_or_404(User, id=id)

    if follower.is_authenticated():
        if follower in target.followers.all():
            target.followers.delete(follower)

        else:
            target.followers.create(follower)  # Error outputs: create() takes 1 positional argument but 2 were given

当我们想为新的关注者创建一行时，会发生错误，提示 create() 接受 1 个位置参数但给出了 2 个我做错了什么？

Answer 1

您需要将关键字参数传递给 create() 方法:

target.followers.create(follower=follower)

或者您可以使用 add() 方法代替:

target.followers.add(follower)

也应该是remove而不是delete:

target.followers.remove(follower)