基于Mixins扩展类和GenericAPIView实现API接口

5个视图扩展类也叫混入类（Mixin）

作用：

提供了几种后端视图（对数据资源进行增删改查）处理流程的实现，如果需要编写的视图属于这五种，则视图可以通过继承相应的扩展类来复用代码，减少自己编写的代码量。

这五个扩展类需要搭配GenericAPIView通用视图基类，因为五个扩展类的实现需要调用GenericAPIView提供的序列化器与数据库查询的方法

1.ListModelMixin

列表视图扩展类，提供list(request, *args, **kwargs)方法快速实现列表视图，返回200状态码。

该Mixin的list方法会对数据进行过滤和分页。

class ListModelMixin:
    """
    List a queryset.
    """
    def list(self, request, *args, **kwargs):
        queryset = self.filter_queryset(self.get_queryset())

        page = self.paginate_queryset(queryset)
        if page is not None:
            serializer = self.get_serializer(page, many=True)
            return self.get_paginated_response(serializer.data)

        serializer = self.get_serializer(queryset, many=True)
        return Response(serializer.data)

2.CreateModelMixin

创建视图扩展类，提供create(request, *args, **kwargs)方法快速实现创建资源的视图，成功返回201状态码。

如果序列化器对前端发送的数据验证失败，返回400错误。

class CreateModelMixin:
    """
    Create a model instance.
    """
    def create(self, request, *args, **kwargs):
        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        self.perform_create(serializer)
        headers = self.get_success_headers(serializer.data)
        return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)

    def perform_create(self, serializer):
        serializer.save()

    def get_success_headers(self, data):
        try:
            return {'Location': str(data[api_settings.URL_FIELD_NAME])}
        except (TypeError, KeyError):
            return {}

3.RetrieveModelMixin

详情视图扩展类，提供retrieve(request, *args, **kwargs)方法，可以快速实现返回一个存在的数据对象。

如果存在，返回200， 否则返回404。

class RetrieveModelMixin:
    """
    Retrieve a model instance.
    """
    def retrieve(self, request, *args, **kwargs):
        instance = self.get_object()
        serializer = self.get_serializer(instance)
        return Response(serializer.data)

4.UpdateModelMixin

更新视图扩展类，提供update(request, *args, **kwargs)方法，可以快速实现更新一个存在的数据对象。

同时也提供partial_update(request, *args, **kwargs)方法，可以实现局部更新。

成功返回200，序列化器校验数据失败时，返回400错误。

class UpdateModelMixin:
    """
    Update a model instance.
    """
    def update(self, request, *args, **kwargs):
        partial = kwargs.pop('partial', False)
        instance = self.get_object()
        serializer = self.get_serializer(instance, data=request.data, partial=partial)
        serializer.is_valid(raise_exception=True)
        self.perform_update(serializer)

        if getattr(instance, '_prefetched_objects_cache', None):
            # If 'prefetch_related' has been applied to a queryset, we need to
            # forcibly invalidate the prefetch cache on the instance.
            instance._prefetched_objects_cache = {}

        return Response(serializer.data)

    def perform_update(self, serializer):
        serializer.save()

    def partial_update(self, request, *args, **kwargs):
        kwargs['partial'] = True
        return self.update(request, *args, **kwargs)

5.DestroyModelMixin

删除视图扩展类，提供destroy(request, *args, **kwargs)方法，可以快速实现删除一个存在的数据对象。

成功返回204，不存在返回404。

class DestroyModelMixin:
    """
    Destroy a model instance.
    """
    def destroy(self, request, *args, **kwargs):
        instance = self.get_object()
        self.perform_destroy(instance)
        return Response(status=status.HTTP_204_NO_CONTENT)

    def perform_destroy(self, instance):
        instance.delete()

整体代码

views:

from .models import Student
from .serializers import StudentModelSerializer
from rest_framework.generics import GenericAPIView
from rest_framework.mixins import ListModelMixin,CreateModelMixin,RetrieveModelMixin,UpdateModelMixin,DestroyModelMixin


class StudentMixinView(GenericAPIView,ListModelMixin,CreateModelMixin):
    queryset=Student.objects.all()
    serializer_class=StudentModelSerializer

    def get(self,request):
        return self.list(request)
    
    def post(self,request):
        return self.create(request)

class StudentInfoMixinView(GenericAPIView,RetrieveModelMixin,UpdateModelMixin,DestroyModelMixin):
    queryset=Student.objects.all()
    serializer_class=StudentModelSerializer

    def get(self,request,pk):
        return self.retrieve(request,pk=pk)

    def put(self,request,pk):
        return self.update(request,pk=pk)
    
    def delete(self,request,pk):
        return self.destroy(request,pk=pk)




    

urls:

from django.urls import path,re_path
from . import views

# 路由列表
urlpatterns = [
    path("students/",views.StudentMixinView.as_view()),
    re_path(r"students/(?P<pk>\d+)/",views.StudentInfoMixinView.as_view())
    
]

 

标签：GenericAPIView,Mixins,self,request,instance,API,def,kwargs,serializer
来源： https://www.cnblogs.com/fuck-Innovative-training/p/16670604.html