Question

我有一个工作函数，我需要向其添加一个新变量，其值将取决于执行代码的哪一部分。

working_code.py

class YoutubeAuthView(APIView):    
    permission_classes = (permissions.IsAuthenticated,)    
    def post(self, request, *args, **kwargs):
        .....
        some code
        .....

        try:
           ...some code...
           try:
              p = Platform.objects.get(
                content_type=ContentType.objects.get_for_model(y),
                object_id=y.id,
                user=request.user
            )
           except:
              p = Platform(user=request.user,
                         platform=y, description=description)

        except Youtube.DoesNotExist:
           p = Platform(user=request.user,
                         platform=y, description=description)                
        return Response(
            PlatformSerializer(p, context={'request': request}).data
        )

现在，我添加变量 NEW

class MyAuthView(APIView):    
    permission_classes = (permissions.IsAuthenticated,)    
    def post(self, request, *args, **kwargs):
        .....
        some code
        .....

        try:
           ...some code...
           try:
              p = Platform.objects.get(
                content_type=ContentType.objects.get_for_model(y),
                object_id=y.id,
                user=request.user
            )
           except:
              p = Platform(user=request.user,
                         platform=y, description=description)
           NEW = False
        except Youtube.DoesNotExist:
           p = Platform(user=request.user,
                         platform=y, description=description)
           NEW = True                
        return Response(?????)

如何在返回值中添加右赋Response变量？像PlatformSerializer(p, context={'request': request, 'new':new}).data

Answer 1

我认为更好的方法是在将此值赋给序列化程序之前先将其分配给对象，例如

    ...
    try:
       ...some code...
       try:
          p = Platform.objects.get(
            content_type=ContentType.objects.get_for_model(y),
            object_id=y.id,
            user=request.user
        )
       except:
          p = Platform(user=request.user,
                     platform=y, description=description)
          p.new = False      ######## here

    except Youtube.DoesNotExist:
       p = Platform(user=request.user,
                     platform=y, description=description)
       p.new = True      ######## here        
    return Response(
        PlatformSerializer(p, context={'request': request}).data
    )

，然后在序列化器中使用SerializerMethodField：

new = serializers.SerializerMethodField()

def get_new(self, obj):
    value = getattr(obj, 'new', False)
    return value

Answer 2

您可以为此重写序列化程序的to_representation方法：

PlatformSerializer(ModelSerializer):
    ...
    def to_representation(self, obj):
        data = super().to_representation(obj)
        data['new'] = self.context.get('new')
        return data

在w视图中：

serializer = PlatformSerializer(p, context={'request': request, 'new':new})
return Response(serializer.data)

将新变量添加到DRF响应

2 个答案: