Django REST Framework为POST/PUT提供了不同的深度？

Question

我正在使用Django REST Framework为我的Web应用程序创建API.我有一个班级'评论',已depth=2在Meta课堂上设定.这很有GET用Comments.当我尝试发送POST或PUT请求(即创建一个新的Comment)时,我被告知我需要包含对象而不是ForeignKey ID.

这是我的Serializer类:

class CommentSerializer(serializers.ModelSerializer):
    class Meta:
        model = Comment
        depth = 2 

该模型:

class Comment(models.Model):
    user = models.ForeignKey(User, null=True, blank=True,
        related_name='comments')
    budget = models.ForeignKey(Budget, related_name='comments')
    published = models.BooleanField(default=False)
    body = models.TextField()
    created = models.DateTimeField(auto_now_add=True)

视图代码:

class Comments(generics.ListCreateAPIView):

    model = Comment
    serializer_class = CommentSerializer

    def pre_save(self, obj):
        obj.user = self.request.user

输出(JSON)中显示的错误是:

{"user": ["This field is required."], "budget": [{"non_field_errors": ["Invalid data"]}]}

发送此原始数据时:

{"budget": 2, "published": true, "body": "Another comment"}

Answer 1

我知道这有点晚了但我最终使用了2个序列化器,如下所示:

class CommentReadSerializer(serializers.ModelSerializer):
    class Meta:
        model = Comment
        depth = 2

class CommentWriteSerializer(serializers.ModelSerializer):
    class Meta:
        model = Comment

然后像这样使用:

class Comments(generics.ListCreateAPIView):

    model = Comment
    serializer_class = CommentReadSerializer

    def create(self, request, *args, **kwargs):
        serializer = CommentWriteSerializer(data=request.DATA, files=request.FILES)
        if serializer.is_valid():
            self.pre_save(serializer.object)
            self.object = serializer.save(force_insert=True)
            self.post_save(self.object, created=True)
            headers = self.get_success_headers(serializer.data)
            serializer = CommentReadSerializer(serializer.object)
            return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)

        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

Answer 2

您可以通过覆盖该get_serializer_class()函数来设置不同的序列化程序，如下所示：

def get_serializer_class(self): method = self.request.method if method == 'PUT' or method == 'POST': return YourWriteSerializer else: return YourReadSerializer

我想添加这个，因为一段时间后我从谷歌搜索来到这里。

Answer 3

我认为定义引用外键关系的序列化器字段的正确方法是通过类似的方式serializers.PrimaryKeyRelatedField.我不相信模型序列化程序会自动使用此字段类,而无需在序列化程序类中明确定义它.

http://www.django-rest-framework.org/api-guide/relations/#primarykeyrelatedfield

我想,PrimaryKeyRelatedField序列化程序可以正确处理JSON数据提交,就像您在示例中使用的那样.