Django，更新数据库列，rest_framework

Question

在更新数据库中的列时有点卡住。我正在发送put 更新列的请求。但返回错误。

assert isinstance(response, HttpResponseBase), ( AssertionError: 预期为 Response、HttpResponse 或 HttpStreamingResponse 从视图返回，但收到<class 'NoneType'>

这里是前端。发送request。

updateInvoceProject(id, company_name){
    return axios.put(API_HANDLER.database_api + "api/v1/update-project", {id, company_name})
},

serializer.py

class InvocesSerializer(serializers.ModelSerializer):
    class Meta:
        model = Invoces
        fields = ("__all__")

查看

@csrf_exempt 
@api_view(["PUT"])
def update(request):
    if request.method == "PUT":
        serializer = InvocesSerializer(data=request.data)
        if serializer.is_valid():
            invoce = Invoces.objects.get(id=serializer.data["id"])
            invoce.company_name = serializer.data["company_name"]
            invoce.save()

            return Response(serializer.data)

网址

urlpatterns = [
    #
    path("api/v1/update-project", invocesView.update, name="update-project"),
    #
]

但最后，我上面提到的错误弹出了。我在这里错过了什么吗？

Answer 1

发生这种情况是因为当序列化数据无效时您没有返回任何内容。

你可以简单地把它变成这样，以确保它在所有情况下都会返回一些东西。

@csrf_exempt 
@api_view(["PUT"])
def update(request):
    # if request.method == "PUT":
    # You don't have to check for method, since you already defined it
    # in api_view(...) decorator.
    serializer = InvocesSerializer(data=request.data)
    # Raises a ValidatinException which will be sent as a 400 response.
    serializer.is_valid(raise_exception=True)
    invoce = Invoces.objects.get(id=serializer.data["id"])
    invoce.company_name = serializer.data["company_name"]
    invoce.save()
    return Response(serializer.data)

---

更好的解决方案

我建议你使用 DRF 的UpdateAPIView (Do it the DRF way :D)，为了避免陷入这样的错误，也避免做所有的验证和序列化手。

如下：

1.保留您的InvocesSerializer，并创建另一个仅用于更新company_name

# Inside serializers.py
class InvocesCompanyNameUpdateSerializer(serializers.ModelSerializer):

    def to_representation(self, instance):
        return InvocesSerializer(instance).to_representation(instance)

    class Meta:
        model = Invoces
        fields = ('company_name',)

2 。为该序列化程序创建一个UpdateAPIView 类

# Inside views.py
class InvoiceUpdateCompanyNameAPIView(UpdateAPIView):
    http_method_names = ['put'] # This is only to allow PUT method on this view.
    serializer_class = InvocesCompanyNameUpdateSerializer
    queryset = Invoces.objects.all()

3 .现在将带有re_path 的视图附加到您的网址。

# Inside urls.py
urlpatterns = [
    #
    # you have to add "pk" url path variable, so DRF use it internally to identify
    # which object you want to update.
    re_path(r"api/v1/update-project/(?P<pk>[\d]+)/", 
        invocesView.InvoiceUpdateCompanyNameAPIView.as_view(), 
        name="update-project"),
    #
]