from rest_framework.mixins import ListModelMixin

class ListModelMixin(object):
  """
  List a queryset.
  """
  def list(self, request, *args, **kwargs):
    # 过滤
    queryset = self.filter_queryset(self.get_queryset())
    # 分页
    page = self.paginate_queryset(queryset)
    if page is not None:
      serializer = self.get_serializer(page, many=True)
      return self.get_paginated_response(serializer.data)
    # 序列化
    serializer = self.get_serializer(queryset, many=True)
    return Response(serializer.data)

from rest_framework.mixins import ListModelMixin
from rest_framework.generics import GenericAPIView

class BookListView(ListModelMixin, GenericAPIView):
  queryset = BookInfo.objects.all()
  serializer_class = BookInfoSerializer

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

from rest_framework.mixins import CreateModelMixin

class CreateModelMixin(object):
  """
  Create a model instance.
  """
  def create(self, request, *args, **kwargs):
    # 获取序列化器
    serializer = self.get_serializer(data=request.data)
    # 验证
    serializer.is_valid(raise_exception=True)
    # 保存
    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 {}

from rest_framework.mixins import RetrieveModelMixin

class RetrieveModelMixin(object):
  """
  Retrieve a model instance.
  """
  def retrieve(self, request, *args, **kwargs):
    # 获取对象，会检查对象的权限
    instance = self.get_object()
    # 序列化
    serializer = self.get_serializer(instance)
    return Response(serializer.data)

from rest_framework.mixins import RetrieveModelMixin
from rest_framework.generics import GenericAPIView

class BookDetailView(RetrieveModelMixin, GenericAPIView):
  queryset = BookInfo.objects.all()
  serializer_class = BookInfoSerializer

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

from rest_framework.mixins import UpdateModelMixin

class UpdateModelMixin(object):
  """
  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)

from rest_framework.mixins import DestroyModelMixin

class DestroyModelMixin(object):
  """
  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()

"""GenericAPIView结合视图扩展类实现api接口"""
from rest_framework.generics import GenericAPIView
from rest_framework.mixins import ListModelMixin,CreateModelMixin

class Students2GenericAPIView(GenericAPIView,ListModelMixin,CreateModelMixin):
  # 本次视图类中要操作的数据[必填]
  queryset = Student.objects.all()
  # 本次视图类中要调用的默认序列化器[玄天]
  serializer_class = StudentModelSerializer

  def get(self, request):
    """获取多个学生信息"""
    return self.list(request)

  def post(self,request):
    """添加学生信息"""
    return self.create(request)

from rest_framework.mixins import RetrieveModelMixin,UpdateModelMixin,DestroyModelMixin
from rest_framework.generics import GenericAPIView

class Student2GenericAPIView(GenericAPIView,RetrieveModelMixin,UpdateModelMixin,DestroyModelMixin):
  queryset = Student.objects.all()

  serializer_class = StudentModelSerializer

  # 在使用GenericAPIView视图获取或操作单个数据时,视图方法中的代表主键的参数最好是pk
  def get(self,request,pk):
    """获取一条数据"""
    return self.retrieve(request,pk)

  def put(self,request,pk):
    """更新一条数据"""
    return self.update(request,pk)

  def delete(self,request,pk):
    """删除一条数据"""
    return self.destroy(request,pk)