1. django模式
def users(request):
user_list = ['alex','oldboy']
return HttpResponse(json.dumps((user_list)))
路由：
url(r'^students/', views.StudentsView.as_view()),
视图： 通过发射来找到对应的方法去执行
from django.views import View
class StudentsView(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')详谈cbv工作模式
基于反射实现根据请求的方式不同，执行不同的方法
原理
-- url -> view方法 -> dispatch方法（反射执行其他：GET/POST/DELETE/PUT）
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')2. 面向对象的继承
多个类共用的功能，为了避免重复编写
from django.views import View
最左原则
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. 面向对象的封装
class File:
文件增删改查方法
Class DB:
数据库的方法
class File:
def __init__(self,a1,a2):
self.a1 = a1
self.xxx = a2
def get:...
def delete:...
def update:...
def add:...
obj1 = File(123,666) 将数据123，666 封装到对象中
obj2 = File(456,999)
from django.test import TestCase
# Create your tests here.
## 封装示例
class Request(object):
def __init__(self,obj): # OBJ=对象B,AUTH的这个对象
self.obj = obj
@property # 静态方法
def user(self): # REQ.USER执行这里，返回 self.obj.authticate() = self.B.authticat() = Auth.authticat() = 'JOKER'
return self.obj.authticate()
class Auth(object):
def __init__(self,name,age): # NAME=JOKER,AGE=18
self.name = name
self.age = age
def authticate(self):
return self.name # 返回类的属性NAME
class APIView(object):
def dispatch(self): # 方法被执行
self.f2() # SELF就是这个类，调用F2()
def f2(self): # 调用属性方法
b = Auth('joker',18) # 实例化Auth，得到对象B
req = Request(b) # 实例化Request，得到对象REQ
print(req.user) #
obj = APIView() # 得到APIView实例化对象OBJ
obj.dispatch() # 调用属性方法4. django中间件
- process_request
- process_view
- process_response
- process_exception
- process_render_template中间件做过什么？
-权限 -登陆验证
4.1 django的csrf是如何实现？
发生在，process_view方法，因为要检查函数是否被装饰器装饰
- 检查视图是否被 @csrf_exempt （免除csrf认证）
- 去请求体或cookie中获取token
请求时候会随机产生字符串，在访问的时候会携带这个随机字符串
4.2 针对django，fbv模式如何关闭验证
from django.views.decorators.csrf import csrf_exempt（无需验证）,csrf_protect（需验证）
找到需要验证的函数，@csrf_exempt，@csrf_protect
MIDDLEWARE = [
'django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware', # 全站使用csrf认证
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
]
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)))
MIDDLEWARE = [
'django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
# 'django.middleware.csrf.CsrfViewMiddleware', # 全站不使用csrf认证
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
]
from django.views.decorators.csrf import csrf_protect
@csrf_protect # 该函数需认证
def users(request):
user_list = ['alex', 'oldboy']
return HttpResponse(json.dumps((user_list)))4.3 针对django, cbv模式如何关闭验证
dispatch函数，或者方法，是通过反射来执行相对应的方法，控制它的验证或不验证
from django.views.decorators.csrf import csrf_exempt（无需验证）,csrf_protect（需验证）
from django.utils.decorators import method_decorator
- @method_decorator(csrf_exempt)
- 在dispatch方法中（单独方法无效）
可以针对验证的函数去写，但是不能单独写，要写在@method_decorator里面
@method_decorator（csrf_exempt），@method_decorator（csrf_protect）
from django.views.decorators.csrf import csrf_exempt, csrf_protect
from django.utils.decorators import method_decorator
class StudentsView(View):
@method_decorator(csrf_exempt) # 无需验证
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')可以针对类，然后指定类里面的方法去验证还是不验证，同样需要写在@method_decorator里面
from django.views.decorators.csrf import csrf_exempt, csrf_protect
from django.utils.decorators import method_decorator
@method_decorator(csrf_exempt, name='dispatch') # 无需验证
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')5. 总结
- cbv
- 本质，基于反射来实现
- 流程：路由，view，dispatch(反射)
- 取消csrf认证（装饰器要加到dispatch方法上且method_decorator装饰）
- csrf
- 基于中间件的process_view方法
- 装饰器给单独函数进行设置（认证或无需认证）
-urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^students/', views.StudentsView.as_view()), 点 as_view查看源码
]
class View(object):
"""
Intentionally simple parent class for all views. Only implements
dispatch-by-method and simple sanity checking.
"""
http_method_names = ['get', 'post', 'put', 'patch', 'delete', 'head', 'options', 'trace']
def __init__(self, **kwargs):
"""
Constructor. Called in the URLconf; can contain helpful extra
keyword arguments, and other things.
"""
# Go through keyword arguments, and either save their values to our
# instance, or raise an error.
for key, value in six.iteritems(kwargs):
setattr(self, key, value)
@classonlymethod
def as_view(cls, **initkwargs):
"""
Main entry point for a request-response process.
"""
for key in initkwargs:
if key in cls.http_method_names:
raise TypeError("You tried to pass in the %s method name as a "
"keyword argument to %s(). Don't do that."
% (key, cls.__name__))
if not hasattr(cls, key):
raise TypeError("%s() received an invalid keyword %r. as_view "
"only accepts arguments that are already "
"attributes of the class." % (cls.__name__, key))
def view(request, *args, **kwargs):
self = cls(**initkwargs)
if hasattr(self, 'get') and not hasattr(self, 'head'):
self.head = self.get
self.request = request
self.args = args
self.kwargs = kwargs
return self.dispatch(request, *args, **kwargs)
view.view_class = cls
view.view_initkwargs = initkwargs
# take name and docstring from class
update_wrapper(view, cls, updated=())
# and possible attributes set by decorators
# like csrf_exempt from dispatch
update_wrapper(view, cls.dispatch, assigned=())
return view
def dispatch(self, request, *args, **kwargs):
# Try to dispatch to the right method; if a method doesn't exist,
# defer to the error handler. Also defer to the error handler if the
# request method isn't on the approved list.
if request.method.lower() in self.http_method_names:
handler = getattr(self, request.method.lower(), self.http_method_not_allowed)
else:
handler = self.http_method_not_allowed
return handler(request, *args, **kwargs)django请求周期
FBV wsgi--中间件--路由--视图--模版--渲染--返回
CBV wsgi--中间件--路由--dispatch
RESTFRAMEWORK wsgi--中间件--路由--dispatch
来源：oschina
链接：https://my.oschina.net/u/4384545/blog/4250960