DRF(Django REST framework)Mixin中的檢視的五個擴充套件類
阿新 • • 發佈:2019-02-08
這五個擴充套件類需要搭配GenericAPIView父類,因為五個擴充套件類的實現需要呼叫GenericAPIView提供的序列化器與資料庫查詢的方法
1)ListModelMixin
列表檢視擴充套件類,提供list(request, *args, **kwargs)方法快速實現列表檢視,返回200狀態碼。
該Mixin的list方法會對資料進行過濾和分頁
原始碼:
class ListModelMixin(object):
"""
List a queryset.
"""
def list(self, request, *args, **kwargs) :
# 過濾
queryset = self.filter_queryset(self.get_queryset())
# 分頁
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)
舉例:
"""使用ListModelMixin+GenericAPIView實現“獲取所有圖書資訊”介面"""
class BookListView(mixins.ListModelMixin,GenericAPIView):
# 指定序列化器
serializer_class = BookInfoSerializer
# 指定查詢集
queryset = BookInfo.objects.all()
def get(self,request):
"""
GET /books/
:param request:請求物件
:return: JSON
"""
return self.list(request)
ListAPIView子類檢視簡化程式碼
"""使用ListAPIView實現“獲取所有圖書資訊”介面"""
class BookListView(ListAPIView):
# 指定序列化器類
serializer_class = BookInfoSerializer
# 指定查詢集
queryset = BookInfo.objects.all()
2)CreateModelMixin
建立檢視擴充套件類,提供create(request, *args, **kwargs)方法快速實現建立資源的檢視,成功返回201狀態碼。
如果序列化器對前端傳送的資料驗證失敗,返回400錯誤。
原始碼:
class CreateModelMixin(object):
"""
Create a model instance.
"""
def create(self, request, *args, **kwargs):
# 獲取序列化器
serializer = self.get_serializer(data=request.data)
# 驗證
serializer.is_valid(raise_exception=True)
# 儲存
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 {}
3) RetrieveModelMixin
詳情檢視擴充套件類,提供retrieve(request, *args, **kwargs)方法,可以快速實現返回一個存在的資料物件。
如果存在,返回200, 否則返回404。
原始碼:
class RetrieveModelMixin(object):
"""
Retrieve a model instance.
"""
def retrieve(self, request, *args, **kwargs):
# 獲取物件,會檢查物件的許可權
instance = self.get_object()
# 序列化
serializer = self.get_serializer(instance)
return Response(serializer.data)
舉例:
class BookDetailView(RetrieveModelMixin, GenericAPIView):
queryset = BookInfo.objects.all()
serializer_class = BookInfoSerializer
def get(self, request, pk):
return self.retrieve(request)
4)UpdateModelMixin
更新檢視擴充套件類,提供update(request, *args, **kwargs)方法,可以快速實現更新一個存在的資料物件。
同時也提供partial_update(request, *args, **kwargs)方法,可以實現區域性更新。
成功返回200,序列化器校驗資料失敗時,返回400錯誤。
原始碼:
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)
5)DestroyModelMixin
刪除檢視擴充套件類,提供destroy(request, *args, **kwargs)方法,可以快速實現刪除一個存在的資料物件。
成功返回204,不存在返回404
原始碼:
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()