Django，在 self 类内的多对多关系中，我如何在ORM方面相互引用？

Question

class User(models.Model):
    name = models.CharField(max_length=100)
    age = models.IntegerField()
    gender = models.IntegerField()
    email = models.CharField(max_length=100)
    password = models.CharField(max_length=255)
    following = models.ManyToManyField("self", related_name='followers')
    objects = UserManager()
    def __repr__(self):
        return "User: {0}".format(self.name)

在我的模型“用户”中，用户可以关注并相互关注。

我可以通过以下方式找到用户正在关注的人:

user1 = User.objects.get(id=1)
following = user1.following.all()

但是，我不知道如何找到用户关注的人。

我尝试过:

user1.followers.all()

因为它是我的模型中以下字段中的 related_name。

有人可以教我如何做到这一点吗？

非常感谢。

Answer 1

您应该通过symmetrical属性为 False。

来自文档:

When Django processes this model, it identifies that it has a ManyToManyField on itself, and as a result, it doesn’t add a followers attribute to the User class. Instead, the ManyToManyField is assumed to be symmetrical – that is, if I am your follower, then you are my follower.

If you do not want symmetry in many-to-many relationships with self, set symmetrical to False. This will force Django to add the descriptor for the reverse relationship, allowing ManyToManyField relationships to be non-symmetrical.

就您而言:

class User(models.Model):
    # ...
    following = models.ManyToManyField('self', related_name='followers', symmetrical=False)
    # ...

然后在您的 views.py 中您可以访问两者:

following = user.following.all()
followers = user.followers.all()

现在与self的关系是非对称的。