def authenticate(self, request):
        return (self.force_user, self.force_token)

    def _not_authenticated(self):
        """
        Set authenticator, user & authtoken representing an unauthenticated request.

        Defaults are None, AnonymousUser & None.
        """
        self._authenticator = None

        if api_settings.UNAUTHENTICATED_USER:
            self.user = api_settings.UNAUTHENTICATED_USER()
        else:
            self.user = None

        if api_settings.UNAUTHENTICATED_TOKEN:
            self.auth = api_settings.UNAUTHENTICATED_TOKEN()
        else:
            self.auth = None

api_settings = APISettings(None, DEFAULTS, IMPORT_STRINGS)

'UNAUTHENTICATED_USER': 'django.contrib.auth.models.AnonymousUser',
 'UNAUTHENTICATED_TOKEN': None,

from django.shortcuts import HttpResponse

from rest_framework.views import APIView#导入rest_framework的试图类

from rest_framework.authentication import BaseAuthentication
from rest_framework import exceptions
from . import models
class CustomAuthenticate(BaseAuthentication):
    """
    All authentication classes should extend BaseAuthentication.
    """

    def authenticate(self, request):
        """
        Authenticate the request and return a two-tuple of (user, token).
        """
        tk = request.query_param.get('tk')      #获取用户输入的token   简化写法，就直接在url中传参了
        token_obj = models.Token.objects.filter(token=tk).first()
        if token_obj:
            return (token_obj.user,token_obj)


        raise exceptions.AuthenticationFailed('请登录')    #抛出异常表示不允许匿名用户访问

        # else:
        #     return (None,None)
    def authenticate_header(self, request):
        """
        Return a string to be used as the value of the `WWW-Authenticate`
        header in a `401 Unauthenticated` response, or `None` if the
        authentication scheme should return `403 Permission Denied` responses.
        """
        pass
class TestView(APIView):
    authentication_classes = [CustomAuthenticate,]          #应用认证配置类
    def get(self,request,*args,**kwargs):
        return HttpResponse('ok')