JSON API 与 Django Rest - 'included' 属性

Question

我正在使用 Django-rest 框架创建 JSON-API。除了 "included" 属性外，我可以按照 JSON-API 文档指定的方式构造 returned JSON 对象。有没有办法包含相关模型的多个序列化对象？

例如

如果我有两个模型类

# Snippet Model
from django.db import models
class Snippet(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    title = models.CharField(max_length=100, blank=True, default='')
    user = models.ForeignKey('auth.User', related_name='snippets')

# Comment Model
from django.db import models
class Comment(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    title = models.CharField(max_length=100, blank=True, default='')
    user = models.ForeignKey('auth.User', related_name='comments')

我有这两个模型的序列化程序：

from rest_framework import serializers
class SnippetSerializer(serializers.ModelSerializer):
     model = Snippet
     fields = ('id','created', 'title')

from rest_framework import serializers
class CommentSerializer(serializers.ModelSerializer):
     model = Comment
     fields = ('id','created', 'title')

我有用户序列化器

# User serializer
from .serializers import SnippetSerializer
from .serializers import CommentSerializer
class UserSerializer(serializers.ModelSerializer):
    included = serializers.SerilizerMethodField()
    class Meta: 
        model = User
        fields = ('id','included')

     def get_included(self, obj):
        included_objs = []
        request = self.context['request']

        # check if requested url has a query parameter "included" 
        query = request.QUERY_PARAMS['included'] if 'included' in  request.QUERY_PARAMS else None
        if query:
             queries = query.split(',')
             if 'included' in queries:
                  snippets = SnippetSerializer(many=True, read_only=True).data
                  comments = CommentSerializer(many=True, read_only=True).data
                  included_objs.append(snippets)
                  included_objs.append(comments)
        return included_objs

并且这些代码没有提供我需要的东西。

中的objective是如果请求url包含一个查询"included"，那么API会return一个JSON带有CommentSerialized的对象'included' 属性下与用户对象相关的 SnippetSerialized 对象。结果应该是这样的。

{
   "id" : 1,
   "included": [
       {'id': 2,'created': "20150729", "title":'snippet' },
       {'id': 2,'created': "20150730", "title":"comment" }, 
       {'id': 3,'created': "20150731", "title":"comment" }, 
   ] 
 }

如果有人能帮助我，那就太好了。谢谢！

Answer 1

为此，我将编写第二个序列化程序：

class IncludedUserSerializer(serializers.ModelSerializer):
      snippets = SnippetSerializer(source = 'snippet_set', many=True)
      comments = CommentSerializer(source = 'comment_set', many=True)

      class Meta:
          model=User
          fields = ('id','snippets', 'comments')

然后在您的视图中覆盖 get_serializer 方法

 def get_serializer(self):
     if self.query_params.get('included', None):
           return IncludedUserSerializer
     else:
           return UserSerializer

Answer 2

项目 django-rest-framework-json-api 最近实现了对此行为的支持。

它的用法是这样的：

class UserSerializer(serializers.Serializer):
    name = serializers.CharField(max_length=200)
    # PostSerializer NOT included directly on the serializer, ResourceRelatedField is 
    # specified as default
    posts = relations.ResourceRelatedField(
        source='post_set', many=True, read_only=True) 

    # specifies serializer to use when passing in the `include` param
    included_serializers = {
        'posts': PostSerializer,
    }

如果我理解得很好，你已经自己实现了JSON-API规范的一部分，所以我不知道你是否可以切换并使用他们的项目。但是看看他们如何实现你想要的可能会有一些帮助。例如，参见 this and this。

JSON API 与 Django Rest - 'included' 属性

JSON API with Django Rest - 'included' attribute

python

django

django-models

django-rest-framework

django-serializer