django之restframework使用 （二）视图三部曲

下面我来来看restframework是如何将冗余的代码一步步的进行封装.

这里主要用到的是多继承

mixin类编写视图

view.py

vfrom rest_framework import mixins
from rest_framework import generics

class AuthorView(mixins.ListModelMixin,mixins.CreateModelMixin,generics.GenericAPIView):
    queryset=Author.objects.all()
    serializer_class =AuthorModelSerializers

    def get(self,request, *args, **kwargs):
        return self.list(request, *args, **kwargs)
    def post(self,request, *args, **kwargs):
        return self.create(request, *args, **kwargs)


class AuthorDetailView(mixins.RetrieveModelMixin,mixins.DestroyModelMixin,mixins.UpdateModelMixin,generics.GenericAPIView):
    queryset = Author.objects.all()
    serializer_class = AuthorModelSerializers

    def get(self,request,*args, **kwargs):
        return self.retrieve(request,*args, **kwargs)

    def delete(self,request,*args, **kwargs):
        return self.destroy(request,*args, **kwargs)

    def put(self,request,*args, **kwargs):
        return self.retrieve(request,*args, **kwargs)

 url

 url(r'^authors/$', views.AuthorModelView.as_view(),name='author')
 url(r'^authors/(?P<pk>d+)/$', views.AuthorModelView.as_view(),name="detailauthor"),

 使用通用的基于类的视图

通过使用mixin类，我们使用更少的代码重写了这些视图，但我们还可以再进一步。REST框架提供了一组已经混合好（mixed-in）的通用视图，我们可以使用它来简化我们的views.py模块。

views.py

from rest_framework import generics


class AuthorView(generics.ListCreateAPIView):
    queryset=Author.objects.all()
    serializer_class =AuthorModelSerializers

class AuthorDetailView(generics.RetrieveUpdateDestroyAPIView):
    queryset = Author.objects.all()
    serializer_class = AuthorModelSerializers

 url

 url(r'^authors/$', views.AuthorModelView.as_view(),name='author')
 url(r'^authors/(?P<pk>d+)/$', views.AuthorModelView.as_view(),name="detailauthor"),

到这里是第二部,但是我们还是需要实例化两个类来对应两个url,为什么要实例两个类,因为每个类都有get方法,

如果不写两个类,怎么知道走哪个get方法?

第三部viewsets.ModelViewSet

views.py:

class BookViewSet(viewsets.ModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializers

 urls.py:

url(r'^books/$', views.BookViewSet.as_view({"get":"list","post":"create"}),name="book_list"), 
url(r'^books/(?P<pk>d+)$', views.BookViewSet.as_view({ 'get': 'retrieve', 'put': 'update', 'patch': 'partial_update', 'delete': 'destroy' }),
name="book_detail"),

from rest_framework import viewsets
class AuthorModelView(viewsets.ModelViewSet):
ModelViewSet--->GenericViewSet--->ViewSetMixin----在这个类下执行了as_view
for method, action in actions.items():
　　#as_view后面的参数被循环后得到了请求key,相对应的方法values
    handler = getattr(self, action) # handler -->getattr(self,list) self--->自己写的类AuthorModelView
    setattr(self, method, handler)   #setattr(self,get,self.list) self.get---->执行self.list

 认证与权限组件

认证组件

局部视图认证

在app01.service.auth.py:

class Authentication(BaseAuthentication):

    def authenticate(self,request):
        token=request._request.GET.get("token")
        token_obj=UserToken.objects.filter(token=token).first()
        if not token_obj:
            raise exceptions.AuthenticationFailed("验证失败!")
        return (token_obj.user,token_obj)

 在views.py：

def get_random_str(user):
    import hashlib,time
    ctime=str(time.time())

    md5=hashlib.md5(bytes(user,encoding="utf8"))
    md5.update(bytes(ctime,encoding="utf8"))

    return md5.hexdigest()


from app01.service.auth import *

from django.http import JsonResponse
class LoginViewSet(APIView):
    authentication_classes = [Authentication,]
    def post(self,request,*args,**kwargs):
        res={"code":1000,"msg":None}
        try:
            user=request._request.POST.get("user")
            pwd=request._request.POST.get("pwd")
            user_obj=UserInfo.objects.filter(user=user,pwd=pwd).first()
            print(user,pwd,user_obj)
            if not user_obj:
                res["code"]=1001
                res["msg"]="用户名或者密码错误"
            else:
                token=get_random_str(user)
                UserToken.objects.update_or_create(user=user_obj,defaults={"token":token})
                res["token"]=token

        except Exception as e:
            res["code"]=1002
            res["msg"]=e

        return JsonResponse(res,json_dumps_params={"ensure_ascii":False})

全局视图认证组件

settings.py配置如下：

REST_FRAMEWORK={
    "DEFAULT_AUTHENTICATION_CLASSES":["app01.service.auth.Authentication",]
}