django drf 级联数据和RetrieveModelMixin

1.定义View

from django.shortcuts import render

from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework import status
from rest_framework.parsers import JSONParser
from rest_framework import mixins, generics
from rest_framework.generics import ListAPIView
from rest_framework.pagination import PageNumberPagination
from goods.models import Goods, GoodsCategory
from goods.serializer import GoodsSerializer, CategorySerializer
from rest_framework import viewsets
from django_filters.rest_framework import DjangoFilterBackend

import django_filters
from rest_framework import filters


class GoodsCategotyList(mixins.ListModelMixin, mixins.RetrieveModelMixin, viewsets.GenericViewSet):
    queryset = GoodsCategory.objects.all().filter(category_type=1)
    serializer_class = CategorySerializer

2.定义Serializer

from rest_framework import serializers
from goods.models import Goods, GoodsCategory



class CategorySerializer3(serializers.ModelSerializer):

    class Meta:
        model = GoodsCategory
        fields = '__all__'

class CategorySerializer2(serializers.ModelSerializer):
    sub_cat = CategorySerializer3(many=True,read_only=True)
    class Meta:
        model = GoodsCategory
        fields = '__all__'

class CategorySerializer(serializers.ModelSerializer):
    sub_cat = CategorySerializer2(many=True,read_only=True)  # many必须指明
    class Meta:
        model = GoodsCategory
        fields = '__all__'

3.配置urls

from django.urls import path, include
import users.urls as userurl
from django.conf.urls import url
from django.views.static import serve
from MxShop.settings import MEDIA_ROOT
from goods.views_base import GoodsListView
from rest_framework.documentation import include_docs_urls
from rest_framework.routers import DefaultRouter
from goods.views import GoodsList,GoodsCategotyList #,CategoryList


router = DefaultRouter()
router.register('goods',GoodsList,base_name='a')
router.register('categorys',GoodsCategotyList)

# goods_list = GoodsListSet.as_view({
#     'get':'list'
# })


urlpatterns = [
    # path('admin/', admin.site.urls),
    url(r'useradmin/', include(userurl)),
    url(r'^media/(?P<path>.*)$', serve, {"document_root": MEDIA_ROOT}),
    url(r'^docs/',include_docs_urls(title='drf文档')),
    url(r'^api-auth/', include('rest_framework.urls',namespace='rest_framework')),
    # url(r'^goods/$', goods_list, name="goods-list"),
    url(r'^',include(router.urls)),
    #url(r'^category/$',CategoryList.as_view())
]

4.test