Question

我正在尝试将评论模型与 auth用户模型的用户名字段相关联。
这是代码

from django.contrib.auth.models import User
from django.db import models
from urllib.parse import urlparse


class Posts(models.Model):
    title = models.CharField(max_length=200)
    url = models.URLField()
    points = models.IntegerField(default=0)
    moderator = models.ForeignKey(User, related_name="moderated_stories")
    voters = models.ManyToManyField(User, related_name="liked_stories", blank=True)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    @property
    def domain(self):
            return urlparse(self.url).netloc

    def __str__(self):
            return self.title + " by " + self.moderator.username

    class Meta:
            verbose_name_plural = "stories"


class Comments(models.Model):

    comment = models.TextField()
    created_at = models.DateTimeField(auto_now_add=True)
    user = models.ForeignKey(User, related_name="commented_on", to_field="username")
    commented_on = models.ForeignKey(Posts, related_name="comments")

    def __str__(self):
            return self.comment + " by " + self.user

    class Meta:
            verbose_name_plural = "comments"

但是在执行查询时会出现以下错误：

>>> post = Posts.objects.get(id=2)
>>> post.comments.all()
django.contrib.auth.models.DoesNotExist: User matching query does not exist.

但是当我执行查询以序列化数据时它可以工作

>>> serializers.serialize('json', post.comments.all())
'[{"model": "news.comments", "pk": 1, "fields": {"comment": "Thanks for sharing
the link :)", "commented_on": 2, "created_at": "2015-09-30T06:01:40.201Z", "user
": 1}}, {"model": "news.comments", "pk": 2, "fields": {"comment": "this is what
i was looking for...!", "commented_on": 2, "created_at": "2015-09-30T06:02:17.4
97Z", "user": 4}}, {"model": "news.comments", "pk": 3, "fields": {"comment": "th
anks for sharing !", "commented_on": 2, "created_at": "2015-09-30T06:02:43.971Z"
, "user": 3}}]'

但序列化数据仍然包含用户的 PK ，而不是用户名。这段代码出了什么问题？

to_field在django中没有在ForeignKey关系中工作

0 个答案: