有没有办法在django rest框架中为嵌套关系（嵌套序列化器class）动态指定查询集

Question

假设我们有两个模型：

class Chapter(models.Model):
    title = models.CharField(max_length=128)
    owner = models.ForeignKey(User, on_delete=models.CASCADE)


class Post(models.Model):
    title = models.CharField(max_length=128)
    body = models.TextField()
    is_archived = models.BooleanField(default=False)
    chapter = models.ForeignKey(Chapter, on_delete=models.CASCADE)

Chapter 模型的默认 ModelViewSet 视图集：

class ChapterViewSet(viewsets.ModelViewSet):
    queryset = Chapter.objects.all()
    serializer_class = ChapterSerializer

关键是 ChapterSerializer 使用 PostSerializer 执行嵌套序列化以在响应中提供 post_set 键。

class PostSerializer(serializers.HyperlinkedModelSerializer):
    detail_url = HyperlinkedIdentityField(view_name='post-detail', read_only=True)

    class Meta:
        fields = ['id', 'title', 'is_archived', 'detail_url']
        model = Post

class ChapterSerializer(serializers.ModelSerializer):
    post_set = PostSerializer(read_only=True, many=True)

    class Meta:
        model = Chapter
        fields = ['id', 'title', 'owner', 'post_set']

问题是如何为这个嵌套 PostSerializer 动态指定查询集。例如，当用户发出 GET 请求时，我只想包含未存档的帖子（is_archived 字段设置为 False），如果已完成请求的用户不是Chapter (request.user != current_chapter.owner) 的所有者。有什么办法可以实现吗？

Answer 1

您可以使用 prefetch_related to prefetch the results used by a nested serializer, this prefetch can be filtered by using a Prefetch 对象，然后这将过滤嵌套结果

class ChapterViewSet(viewsets.ModelViewSet):
    queryset = Chapter.objects.all()
    serializer_class = ChapterSerializer

    def get_queryset(self):
        queryset = super().get_queryset()
        return queryset.prefetch_related(
            Prefetch('post_set', queryset=Post.objects.filter(is_archived=False))
        )

在get_queryset方法中你必须动态执行预取，当前请求可以通过self.request

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有没有办法在django rest框架中为嵌套关系（嵌套序列化器class）动态指定查询集

Is there a way to dynamically specify a queryset for nested relationship (nested serializer class) in django rest framework

django

django-rest-framework

django-serializer

django-rest-viewsets