02-Django REST framwork 板块(02-CBV、FBV详解)

文章目录

一、CBV / FBV处理请求的实现方式二、CBV详解1.原理：2.流程3.CBV对csrf的实现 三、注意点1. CSRF基于Django的中间件的实现2. CSRF两种配置方式

一、CBV / FBV处理请求的实现方式

1.一个是基于类写的，一个是基于函数写的，本质上区别不大。 2.推荐CBV方式来写，因为里边直接对请求方式进行了判断

# 基于FBV (function base view) urlpatterns = [ url(r'^order/', views.order), ] # 视图 view.py def order(request): if request.method == 'GET': return HttpResponse('获取订单') elif request.method == 'POST': return HttpResponse('创建订单') elif request.method == 'PUT': return HttpResponse('更新订单') elif request.method == 'DELETE': return HttpResponse('删除订单') # 基于CBV (class base view) # 根据请求method的不同，进行对应dispatch，做不同操作 urlpatterns = [ url(r'^order/', views.OrderView.as_view()), ] # 视图 view.py class OrderView(View): # view内部实现请求分发机制（dispatch） def get(self,request,*args,**kwargs): return HttpResponse('获取订单') def post(self,request,*args,**kwargs): return HttpResponse('创建订单') def put(self,request,*args,**kwargs): return HttpResponse('更新订单') def delete(self,request,*args,**kwargs): return HttpResponse('删除订单')

二、CBV详解

CBV，基于反射实现根据请求方式不同，执行不同的方法。 (与装饰器功能特别相似）对请求进行检测dispatch分发，发到对应的post/get等方法

1.原理：

- `入口 as_view --> view(基于View基类) --> dispatch` - `路由url --> view方法.as_view() --> dispatch方法（反射执行其他：GET/POST/DELETE/PUT）`

2.流程

class StudentsView(View): def dispatch(self, request, *args, **kwargs): print('before') ret = super(StudentsView,self).dispatch(request, *args, **kwargs) print('after') return ret def get(self,request,*args,**kwargs): return HttpResponse('GET') def post(self, request, *args, **kwargs): return HttpResponse('POST') def put(self, request, *args, **kwargs): return HttpResponse('PUT') def delete(self, request, *args, **kwargs): return HttpResponse('DELETE') # 继承（多个类共用的功能，为了避免重复编写，可以基于继承来实现）： from django.views import View class MyBaseView(object): def dispatch(self, request, *args, **kwargs): print('before') ret = super(MyBaseView,self).dispatch(request, *args, **kwargs) print('after') return ret class StudentsView(MyBaseView,View): def get(self,request,*args,**kwargs): print('get方法') return HttpResponse('GET') def post(self, request, *args, **kwargs): return HttpResponse('POST') def put(self, request, *args, **kwargs): return HttpResponse('PUT') def delete(self, request, *args, **kwargs): return HttpResponse('DELETE') class TeachersView(MyBaseView,View): def get(self,request,*args,**kwargs): return HttpResponse('GET') def post(self, request, *args, **kwargs): return HttpResponse('POST') def put(self, request, *args, **kwargs): return HttpResponse('PUT') def delete(self, request, *args, **kwargs): return HttpResponse('DELETE')

3.CBV对csrf的实现

@method_decorator(csrf_exempt) 在dispatch上添加（单独的请求添加无效） # 方式一： from django.views.decorators.csrf import csrf_exempt,csrf_protect from django.utils.decorators import method_decorator class StudentsView(View): @method_decorator(csrf_exempt) def dispatch(self, request, *args, **kwargs): return super(StudentsView,self).dispatch(request, *args, **kwargs) def get(self,request,*args,**kwargs): print('get方法') return HttpResponse('GET') def post(self, request, *args, **kwargs): return HttpResponse('POST') def put(self, request, *args, **kwargs): return HttpResponse('PUT') def delete(self, request, *args, **kwargs): return HttpResponse('DELETE') # 方式二： from django.views.decorators.csrf import csrf_exempt,csrf_protect from django.utils.decorators import method_decorator @method_decorator(csrf_exempt,name='dispatch') class StudentsView(View): def get(self,request,*args,**kwargs): print('get方法') return HttpResponse('GET') def post(self, request, *args, **kwargs): return HttpResponse('POST') def put(self, request, *args, **kwargs): return HttpResponse('PUT') def delete(self, request, *args, **kwargs): return HttpResponse('DELETE')

三、注意点

1. CSRF基于Django的中间件的实现

Django中间件（最多五个） - process_request - process_view - process_response - process_exception - process_render_templateDjango中间件的执行顺序？使用中间件做啥？ 权限用户登录验证 Django的CSRF是如何实现的？ process_view方法（为什么在这？只有到这才能找到那个装饰器函数，才能进行处理）

2. CSRF两种配置方式

# 情况一（全局配置认证，个别函数不配置）： MIDDLEWARE = [ 'django.middleware.csrf.CsrfViewMiddleware', # 全站使用csrf认证 ] from django.views.decorators.csrf import csrf_exempt @csrf_exempt # 该函数无需认证 def users(request): user_list = ['alex','oldboy'] return HttpResponse(json.dumps((user_list))) # 情况二（全局不配置认证，个别配置）： MIDDLEWARE = [ #'django.middleware.csrf.CsrfViewMiddleware', # 注掉这个中间件，表示全站不使用csrf认证 ] from django.views.decorators.csrf import csrf_exempt @csrf_protect # 该函数需认证 def users(request): user_list = ['alex','oldboy'] return HttpResponse(json.dumps((user_list)))