Django REST Framework POST/PUT 的不同深度？

Question

我正在使用 Django REST Framework 為我的 Web 應用程序創建 API。 我有一個“評論”類，在Meta類中設置了depth=2 。 這在GET ing the Comments時效果很好。 當我嘗試發送POST或PUT請求時（即創建一個新的Comment ），我被告知我需要包含對象而不是外鍵 ID。

這是我的 Serializer 類：

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

該模型：

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)

視圖代碼：

class Comments(generics.ListCreateAPIView):

    model = Comment
    serializer_class = CommentSerializer

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

輸出（JSON）中顯示的錯誤是：

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

發送此原始數據時：

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

Answer 1

我知道這有點晚了但我最終使用了2個序列化器，如下所示：

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

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

然后像這樣使用：

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

我認為定義引用外鍵關系的序列化器字段的正確方法是通過類似serializers.PrimaryKeyRelatedField 。 我不相信模型序列化程序會自動使用此字段類而不在序列化程序類中顯式定義它。

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

我想， PrimaryKeyRelatedField序列化程序將正確處理JSON數據提交，就像您在示例中使用的那樣。

Answer 3

您可以通過覆蓋get_serializer_class()函數來設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

我想添加這個，因為我一段時間后從谷歌來到這里。

Answer 4

我遇到了同樣的問題，所以我解決了制作自定義泛型方法。這是上述答案的更好實現

class CustomListCreateAPIView(mixins.ListModelMixin,
                    mixins.CreateModelMixin,
                    generics.GenericAPIView):
"""
Concrete view for listing a queryset or creating a model instance.
"""
def get_serializer_class(self):
    method = self.request.method
    if method == 'PUT' or method == 'POST':
        return self.writeSerializers
    else:
        return self.readSerializers
def get(self, request, *args, **kwargs):
    return self.list(request, *args, **kwargs)

def post(self, request, *args, **kwargs):
    return self.create(request, *args, **kwargs)

同樣的路德，

class CustomRetrieveUpdateDestroyAPIView(mixins.RetrieveModelMixin,
                               mixins.UpdateModelMixin,
                               mixins.DestroyModelMixin,
                               generics.GenericAPIView):
"""
Concrete view for retrieving, updating or deleting a model instance.
"""
def get_serializer_class(self):
    method = self.request.method
    if method == 'PUT' or method == 'POST':
        return self.writeSerializers
    else:
        return self.readSerializers

def get(self, request, *args, **kwargs):
    return self.retrieve(request, *args, **kwargs)

def put(self, request, *args, **kwargs):
    return self.update(request, *args, **kwargs)

def patch(self, request, *args, **kwargs):
    return self.partial_update(request, *args, **kwargs)

def delete(self, request, *args, **kwargs):
    return self.destroy(request, *args, **kwargs)enter code here

現在我只在 Views.py 中給出writeSerializers和readSerializers值

也有一個簡單的方法來創建讀寫序列化程序。

class employeeWriteSerializer(serializers.ModelSerializer):
    class Meta:
        model = employee
        fields = ('username','email',..)
    
class employeeReadSerializer(serializers.ModelSerializer):
     class Meta(employeeWriteSerializer.Meta):
         depth = 1

它可以節省時間和重復性工作，您還可以在自定義通用 Api（Retitve 工作）中添加身份驗證類。 謝謝。