我应该发送什么样的API请求来接收图形参数？

Question

我有个关于django的博客。我有两篇模型文章和评论。每个注释都可以添加到另一个注释中。如果我发送一个API请求localhost:8000/ comments /1，我将收到带有id="1“和所有嵌套注释到第三层的注释。

api请求后的json localhost:8000/comments/：

HTTP 200 OK
Allow: GET, POST, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

[
    {
        "id": 9,
        "text": "First comment",
        "owner": "alex",
        "article": 3,
        "parent": null,
        "reply_set": [
            {
                "id": 10,
                "text": "Comment to comment",
                "owner": "alex",
                "article": 3,
                "parent": 9,
                "reply_set": [
                    {
                        "id": 11,
                        "text": "Third level nested comment",
                        "owner": "alex",
                        "article": 3,
                        "parent": 10
                    }
                ]
            }
        ]
    },
    {
        "id": 10,
        "text": "Comment to comment",
        "owner": "alex",
        "article": 3,
        "parent": 9,
        "reply_set": [
            {
                "id": 11,
                "text": "Third level nested comment",
                "owner": "alex",
                "article": 3,
                "parent": 10,
                "reply_set": [
                    {
                        "id": 12,
                        "text": "Forth level nested comment",
                        "owner": "alex",
                        "article": 3,
                        "parent": 11
                    }
                ]
            }
        ]
    },
    {
        "id": 11,
        "text": "Third level nested comment",
        "owner": "alex",
        "article": 3,
        "parent": 10,
        "reply_set": [
            {
                "id": 12,
                "text": "Forth level nested comment",
                "owner": "alex",
                "article": 3,
                "parent": 11,
                "reply_set": []
            }
        ]
    },
    {
        "id": 12,
        "text": "Forth level nested comment",
        "owner": "alex",
        "article": 3,
        "parent": 11,
        "reply_set": []
    }
]

如何与所有其他嵌套注释一起接收第三级注释？我应该用视图和urls写什么？

评论模式：

class Comment(models.Model):
    date_pub = models.DateTimeField(auto_now_add=True)
    text = models.TextField(blank=False)
    owner = models.ForeignKey('auth.User', related_name='comments', on_delete=models.CASCADE)
    article = models.ForeignKey('Article', related_name='comments', on_delete=models.CASCADE)
    parent = models.ForeignKey('self', related_name='reply_set', null=True, on_delete=models.PROTECT)

    class Meta:
        ordering = ['date_pub']

注释序列化程序：

class RecursiveSerializer(serializers.Serializer):
    def to_representation(self, value):
        serializer = self.parent.parent.__class__(value, context=self.context)
        return serializer.data


class CommentSerializer(serializers.ModelSerializer):
    owner = serializers.ReadOnlyField(source='owner.username')
    reply_set = RecursiveSerializer(many=True, read_only=True)

    class Meta:
        model = Comment
        fields = ['id', 'text', 'owner', 'article', 'parent', 'reply_set']

评论意见

class CommentList(generics.ListCreateAPIView):
    queryset = Comment.objects.all()
    serializer_class = serializers.CommentSerializer
    permission_classes = [permissions.IsAuthenticatedOrReadOnly]

    def perform_create(self, serializer):
        serializer.save(owner=self.request.user)

class CommentDetail(generics.RetrieveUpdateDestroyAPIView):
    queryset = Comment.objects.all()
    serializer_class = serializers.CommentSerializer
    permission_classes = [permissions.IsAuthenticatedOrReadOnly,
                          IsOwnerOrReadOnly]

在urlpatterns模式中：

path('comments/', views.CommentList.as_view()),
path('comments/<int:pk>/', views.CommentDetail.as_view())

Answer 1

如果您的问题是如何接收到特定的第一级评论的所有三级评论(没有他们的父母只是第三级评论)，那么您可以像这样过滤查询集

third_level_comment = Comment.objects.filter(replay_set__replay_set__id = <the 1st level comment id>)

您使用"__“下面的”双倍“来提升关系链上的一个级别。