使用 Django Rest Framework 序列化查询集时的“ListSerializer”

Question

我有一个稍微复杂的 APIView，这使得我无法使用通用的ListAPIView返回查询集。但我似乎无法简单地使用 ModelSerializer 序列化一个简单的 Django 查询集，即使我设置了many=True.

不知怎的，这不起作用：

序列化器.py：

class SomeModelSerializer(serializers.ModelSerializer):

    class Meta:
        model = SomeModel
        fields = ['some_field']

视图.py：

from rest_framework.response import Response

class SomeAPIView(APIView):
    serializer_class = SomeInputSerializer

    def post(self, request, format=None):
        serializer = self.serializer_class(data=request.data)
        if serializer.is_valid():
            # first some business logic, then return results
            results = SomeModel.objects.all()
            output_serializer = SomeModelSerializer(results, many=True)
            return Response(output_serializer.data)

我不断得到的是：'ListSerializer' object is not iterable。

我究竟做错了什么？

错误：

/projectfolder/venv/lib/python2.7/site-packages/django/template/defaulttags.py in render
            try:
                values = self.sequence.resolve(context, True)
            except VariableDoesNotExist:
                values = []
            if values is None:
                values = []
            if not hasattr(values, '__len__'):
                values = list(values) ...
            len_values = len(values)
            if len_values < 1:
                return self.nodelist_empty.render(context)
            nodelist = []
            if self.is_reversed:
                values = reversed(values)

values = list(values)似乎对错误负责

Answer 1

遇到了和你一样的问题。我找到了一个快速简单的错误修复方法：将序列化器数据复制到一个新数组并返回它。

results = SomeModel.objects.all()

output_serializer = SomeModelSerializer(results, many=True)    
data = output_serializer.data[:]

return Response(data)

这对我有用，希望对你也有用。

Answer 2

下面使用 as_view() url 对我有用：

 class ListCreateMemberViewSet(generics.ListCreateAPIView):
        """
        API endpoint that allows multiple members to be created.
        """
        queryset = Member.objects.none()
        serializer_class = MemberSerializer

    def get_queryset(self):
         queryset = Member.objects.all()
         return queryset

    def create(self, request, *args, **kwargs):
        serializer = self.get_serializer(data=request.data, many=isinstance(request.data, list))
        serializer.is_valid(raise_exception=True)
        self.perform_create(serializer)
        results = Member.objects.all()
        output_serializer = MemberSerializer(results, many=True)
        data = output_serializer.data[:]
        return Response(data)