Django views 中的装饰器

关于装饰器

示例：
有返回值的装饰器：判断用户是否登录，如果登录继续执行函数，否则跳回登录界面

def auth(func):
    def inner(request, *args, **kwargs):
        username = request.COOKIES.get('username')
        if not username:
            # 如果无法获取 'username' COOKIES，就跳转到 '/login.html'
            return redirect('/login.html')
        # 原函数执行前
        res = func(request, *args, **kwargs)
        # 原函数执行后
        return res
    return inner

FBV:

直接在需要装饰到函数上面加上@auth

@auth
def index(request):
    return render(request, 'index.html')

CBV:

关于 CBV

只需要给部分方法加上装饰器

from django import views
from django.utils.decorators import method_decorator


class Order(views.View):

	@method_decorator(auth)
	def get(self,reqeust):
		v = reqeust.COOKIES.get('username')
		return render(reqeust,'index.html',{'current_user': v})

	def post(self,reqeust):
		v = reqeust.COOKIES.get('username')
		return render(reqeust,'index.html',{'current_user': v})

需要给所有方法加上装饰器

通过 dispatch 实现

from django import views
from django.utils.decorators import method_decorator


class Order(views.View):

	@method_decorator(auth)
	def dispatch(self, request, *args, **kwargs):
	    return super(Order,self).dispatch(request, *args, **kwargs)

	def get(self,reqeust):
		v = reqeust.COOKIES.get('username')
		return render(reqeust,'index.html',{'current_user': v})

	def post(self,reqeust):
		v = reqeust.COOKIES.get('username')
		return render(reqeust,'index.html',{'current_user': v})

直接在类上给 dispatch 添加装饰器

from django import views
from django.utils.decorators import method_decorator


@method_decorator(auth,name='dispatch')
class Order(views.View):

	def get(self,reqeust):
		v = reqeust.COOKIES.get('username')
		return render(reqeust,'index.html',{'current_user': v})

	def post(self,reqeust):
		v = reqeust.COOKIES.get('username')
		return render(reqeust,'index.html',{'current_user': v})