DRF视图的三次封装

DRF视图相关的类

from rest_framework import views
from rest_framework import generics
from rest_framework import mixins
from rest_framework import viewsets

 第一次封装：

1.定义一个通用类

from rest_framework.views import APIView

class GenericAPIView(APIView):
    query_set = None
    serializer_class = None

    def get_queryset(self):
        return self.query_set

    def get_serializer(self, *args, **kwargs):
        return self.serializer_class(*args, **kwargs)

 2.抽离出get/post/put方法：

class ListModelMixin(object):
    # list 对应get请求，全部查找
    def list(self, request):
        queryset = self.get_queryset()
        ret = self.get_serializer(queryset, many=True)
        return Response(ret.data)


class CreateModelMixin(object):
    # create 对应post请求
    def create(self, request):
        serializer = self.get_serializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)


class RetrieveModelMixin(object):
    # retrieve 对应get请求（含id），具体查找某一条数据
    def retrieve(self, request, id):
        book_obj = self.get_queryset().filter(id=id).first()
        ret = self.get_serializer(book_obj)
        return Response(ret.data)


class UpdateModelMixin(object):
    # update 对应put请求
    def update(self, request, id):
        book_obj = self.get_queryset().filter(id=id).first()
        serializer = self.get_serializer(book_obj, data=request.data, partial=True)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)


class DestroyModelMixin(object):
    # destory 对应 DELETE 请求
    def destroy(self, request, id):
        book_obj = self.get_queryset().filter(id=id).first()
        book_obj.delete()
        return Response("")

 3.在视图中调用

class BookView(GenericAPIView, ListModelMixin, CreateModelMixin):
    query_set = Book.objects.all()
    serializer_class = BookSerializer

    def get(self, request):
        book_obj = Book.objects.first()
        ret = BookSerializer(book_obj)
        book_list = Book.objects.all()
        book_list = self.get_queryset()
        ret = self.get_serializer(book_list, many=True)
        return Response(ret.data)

    def post(self, request):
        print(request.data)
        serializer = BookSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)

 第二次封装：

整合需要继承的类，然后让视图类来继承这个新的类

class ListCreateAPIView(GenericAPIView, ListModelMixin, CreateModelMixin):
    pass

class BookView(ListCreateAPIView):
    query_set = Book.objects.all()
    serializer_class = BookSerializer

    def get(self, request):
        book_obj = Book.objects.first()
        ret = BookSerializer(book_obj)
        book_list = Book.objects.all()
        book_list = self.get_queryset()
        ret = self.get_serializer(book_list, many=True)
        return Response(ret.data)

    def post(self, request):
        print(request.data)
        serializer = BookSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        else:
            return Response(serializer.errors)

 第三次封装：

合并视图

想要合并视图，就需要给as_view传参，因此我们需要继承一个能够为as_view传参的类，即ViewSetMixin;
ViewSetMinix将get/post/put等请求与action:list/create/update形成对应关系，通过dispath分发，实现视图的合并;
因此我们需要自定义一个继承ViewSetMixin的CBV：ModelViewSet，并让视图类继承ModelViewSet;

class ModelViewSet(ViewSetMixin, GenericAPIView, ListModelMixin, CreateModelMixin, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin):
    pass
    
class BookModelViewSet(ModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializer

 在rest_framework中为我们提供了ModelViewSet

from rest_framework.viewsets import ModelViewSet