先來看看之前優化的程式碼：

from rest_framework.generics import GenericAPIView
from django_filters.rest_framework import DjangoFilterBackend
from rest_framework.filters import OrderingFilter
from rest_framework.mixins import ListModelMixin, CreateModelMixin, RetrieveModelMixin, UpdateModelMixin, DestroyModelMixin
 
from utils.pagination import NewPagination
from .models import Projects
from .serializers import ProjectsModelSerializer


class ProjectsPage(ListModelMixin,
                   CreateModelMixin,
                   GenericAPIView):
    '''
    類檢視
    '''
    queryset = Projects.objects.all()
    serializer_class 
 
= ProjectsModelSerializer

    filter_backends = [DjangoFilterBackend, OrderingFilter]
    filterset_fields = ['id', 'name', 'leader', 'programmer', 'tester']
    ordering_fields = ['id', 'name', 'leader', 'programmer', 'tester']
    pagination_class = NewPagination

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

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


class ProjectsDetailsPage(RetrieveModelMixin,
                          UpdateModelMixin,
                          DestroyModelMixin,
                          GenericAPIView):
    
    queryset = Projects.objects.all()
    serializer_class = ProjectsModelSerializer
    
    def get(self, request, *args, **kwargs):
        self.retrieve(request, *args, **kwargs)

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

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

上面的程式碼優化只針對當前檢視，一般一個專案會有很多個檢視，如果有很多檢視結構都跟上面的相似，那可不可以不要每次都cv這些請求方法呢？

本章我們通過generics模組中的一系列類來繼續優化檢視當中的請求方法，先看看generics模組的Structure:

generics模組下主要有以下類來做優化

• CreateAPIView：繼承了mixins.CreateModelMixin和GenericAPIView
• ListAPIView：繼承了mixins.ListModelMixin和GenericAPIView
• RetrieveAPIView：繼承了mixins.RetrieveModelMixin和GenericAPIView
• DestroyAPIView：繼承了mixins.DestroyModelMixin和GenericAPIView
• UpdateAPIView：繼承了mixins.UpdateModelMixin和GenericAPIView
• ListCreateAPIView：繼承了mixins.ListModelMixin、mixins.CreateModelMixin和GenericAPIView
• RetrieveUpdateAPIView：繼承了mixins.RetrieveModelMixin、mixins.UpdateModelMixin和GenericAPIView
• RetrieveDestroyAPIView：繼承了mixins.RetrieveModelMixin、mixins.DestroyModelMixin和GenericAPIView
• RetrieveUpdateDestroyAPIView：繼承了mixins.RetrieveModelMixin、mixins.UpdateModelMixin、mixins.DestroyModelMixin和GenericAPIView

由於ProjectsPage檢視類有獲取專案列表資訊的get請求和建立專案的post請求，因此可以繼承ListCreateAPIView類來進行優化

class ProjectsPage(ListCreateAPIView):
    '''
    類檢視
    '''
    queryset = Projects.objects.all()
    serializer_class = ProjectsModelSerializer

    filter_backends = [DjangoFilterBackend, OrderingFilter]
    filterset_fields = ['id', 'name', 'leader', 'programmer', 'tester']
    ordering_fields = ['id', 'name', 'leader', 'programmer', 'tester']
    pagination_class = NewPagination

ProjectsDetailsPage檢視類有獲取專案詳情的get請求，更新的put請求和刪除專案的delete請求，因此可以繼承RetrieveUpdateDestroyAPIView類來進行優化

class ProjectsDetailsPage(RetrieveUpdateDestroyAPIView):

    queryset = Projects.objects.all()
    serializer_class = ProjectsModelSerializer