如何：创建一个视图和序列化器，用于添加，编辑和删除具有外部关系的对象django rest framework

Posted 2021-04-06

我很难连接django和django rest框架上关于如何创建允许外键的视图和序列化器的所有文档。

编辑：我可能在这里有一个答案：http://www.django-rest-framework.org/api-guide/relations/#writable-nested-serializers

示例I具有这些模型。

class SearchCity(models.Model):
    city = models.CharField(max_length=200)

class SearchNeighborhood(models.Model):
    city = models.ForeignKey(SearchCity, on_delete=models.CASCADE)
    neighborhood = models.CharField(max_length=200)

我希望能够选择一个城市，然后查看该城市所有的社区，并能够添加社区，编辑和社区，并删除一个社区。

所以也许是一个城市拥有所有社区的网址或为城市创建一个新的社区

url(r'^neighborhood/(?P<citypk>[0-9]+)$', SearchNeighborhoodListCreate.as_view()),

和一个编辑和删除邻居：

url(r'^neighborhood/(?P<citypk>[0-9]+)/(?P<neighborhoodpk>[0-9]+)$',SearchNeighborhoodDetail.as_view()),

我目前正在使用来自DRF Generics的ListCreateAPIView和RetreiveUpdateDestoryAPIView

我知道我们有像query_setrelated这样的选项，可以让我们获得模型所具有的所有关系。

我知道我们有x_set选项。在我的例子中使用这样的。 Searchcity.SearchNeighborhood_set.all()

我知道我们有相关的序列化器

并且我创建它们的正确方法是这样的：

class CityNeighborhoodSerializer(serializers.ModelSerializer):
    neighborhood = serializers.PrimaryKeyRelatedField(many=True, read_only=False)

    class Meta:
        model = SearchCity
        fields = ('City', 'neighborhood')

但是我如何在这个用例中使用它呢？

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

关于链接在这里http://gregblogs.com/tlt-how-to-retrieve-the-fields-of-a-related-model-from-a-django-rest-framework-endpoint/的关系中的所有对象有一个很好的参考

但这与编辑，删除，相关的对象有关吗？

最后我做了大量的研究，但我正在寻求帮助填补裂缝并真正理解这件事。这是一个常见的用例，我相信你们中的许多人以前都做过。

编辑：

看起来这个问题间接地回答了我的问题，但我仍然不确定。我将继续关注它并测试它。看看我发现了什么。

Deletion objects that is used as foreign key

答案

以下是我对此的看法：

网址：

url(r'^city/(?P<city_pk>[0-9]+)/neighborhood/', SearchNeighborhoodListCreateView.as_view()),
url(r'^city/(?P<city_pk>[0-9]+)/neighborhood/(?P<pk>[0-9]+)$', SearchNeighborhoodDetailView.as_view()),

由于每个城市都有一个或多个社区

串行器：

• 只需像这样为SearchNeighborhood创建一个序列化器： class NeighborhoodSerializer(serializers.ModelSerializer): class Meta: model = SearchNeighborhood fields = ('id', 'city', 'neighborhood')
• 如果你想要你所在城市api的社区列表，你可以使用这个： class CityNeighborhoodSerializer(serializers.ModelSerializer): neighborhoods = NeighborhoodSerializer(many=True, source='searchneighborhood_set.all') class Meta: model = SearchCity fields = ('city', 'neighborhoods')

我建议在SearchNeighborhood领域的city模型上有一个相关的名字，例如：related_name='neighborhoods'，那么你可以使用source='neighborhoods.all'，它更具可读性。

观点：这里的诀窍是只获得与城市相关的社区

class SearchNeighborhoodListCreateView(generics.ListCreateAPIView):
    queryset = SearchNeighborhood.objects.all()
    serializer_class = NeighborhoodSerializer

    def get_city(self):
        queryset = SearchCity.objects.all()
        return get_object_or_404(queryset, pk=self.kwargs['city_pk'])

    def get_queryset(self):
        city = self.get_city()
        return super().get_queryset().filter(city=city)

    def perform_create(self, serializer):
        city = self.get_city()
        serializer.save(city=city)

希望你能得到主要的想法。

另一答案

在这里，我再次回答我自己的问题......

最好的方法是创建自己的视图，用于按城市创建和获取对象。

# create and get list of Search Neighborhood objects by city
class CityNeighborhoodsListCreate(APIView):

    # this get request gets all the neighborhoods by city
    def get (self, request, format=None, *args, **kwargs):
        citypk = kwargs.get('citypk', None)
        city = get_object_or_404(SearchCity,pk=citypk)
        neighborhoods = city.searchneighborhood_set.all()
        serialized = SearchNeighborhoodSerializer(neighborhoods, many=True)
        return Response({
            'neighborhoods': serialized.data
        })

    def post(self, request, *args, **kwargs):
        citypk = kwargs.get('citypk', None)
        city=get_object_or_404(SearchCity,pk=citypk)
        serialized = SearchNeighborhoodSerializer(data=request.data)
        if serialized.is_valid(raise_exception=True):
            validatedData = serialized.validated_data
            neighborhood = validatedData.get('neighborhood')
            neighborhoodobject = SearchNeighborhood(neighborhood= neighborhood, city = city)
            neighborhoodobject.save()
            createdneighborhood = SearchNeighborhoodSerializer(neighborhoodobject)
            return Response({
                'neighborhood': createdneighborhood.data
            })