DRF序列化程序自定义创建

Question

我不知道我这样做是否正确，但我在保存与DRF串行化程序的关系方面有问题。

假设我有一个MessageBoard和一些MessageBoardPosts

Post有一个序列化程序，类似于：

class MessageBoardPostSerializer(serializers.ModelSerializer):
  class Meta:
      model = MessageBoardPost
      fields = '__all__'

我想通过投递到/api/ MessageBoard /PK/create/来添加一个Post，为此，我向MessageBoard视图集添加了一个操作：

@action(detail=True, methods=['post'], permission_classes=[MatchesMessageboardVisibility])
def create_post(self, request, pk=None):
    # Messageboard to post to
    messageBoard = MessageBoard.objects.get(pk=pk)

    if messageBoard is not None:
        serializer = MessageBoardPostSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        serializer.save()
    return Response(serializer.data)

由于MessageBoard是post上必需的FK，所以在视图集中创建post时，我会得到验证错误。

解决这个问题的最好方法是什么？

Answer 1

序列化程序(我假设"message_board“是MessageBoardPost模型中的ForeignKey )：

class MessageBoardPostSerializer(serializers.ModelSerializer):
  # this is read only by default which means serializer will not require that field 
  message_board = serializers.StringRelatedField() 

  class Meta:
      model = MessageBoardPost
      fields = '__all__'

Viewset操作：

@action(detail=True, methods=['post'], permission_classes=[MatchesMessageboardVisibility])
def create_post(self, request, pk=None):
    # Messageboard to post to
    messageBoard = get_object_or_404(MessageBoard, pk=pk)

    serializer = MessageBoardPostSerializer(data=request.data)
    serializer.is_valid(raise_exception=True)

    # here you can pass data without validation directly to the save method
    serializer.save(message_board=messageBoard)
    return Response(serializer.data)

• 您应该以snake_case样式(如" message_board“等)编写变量。对于更高级的crud，应该使用
• ，您应该使url /api/留言板/PK/ POST /在其中发布您的帖子，而message_board应该在过高的初始方法

中预取。

Answer 2

可以将MessageBoard作为上下文传递给序列化程序：

views.py

from django.shortcuts import get_object_or_404

@action(detail=True, methods=['post'], permission_classes=[MatchesMessageboardVisibility])
def create_post(self, request, pk=None):
    # Messageboard to post to
    message_board = get_object_or_404(MessageBoard, pk=pk)

    context = {'message_board': message_board}
    serializer = MessageBoardPostSerializer(data=request.data, context=context)
    serializer.is_valid(raise_exception=True)
    serializer.save()
    return Response(serializer.data)

serializers.py

class MessageBoardPostSerializer(serializers.ModelSerializer):
    class Meta:
        model = MessageBoardPost
        fields = '__all__'

    def create(self, validated_data):
        post = MessageBoardPost(**validated_data)
        post.message_board = self.context['message_board']
        post.save()
        return post