zoukankan      html  css  js  c++  java
  • Django Restful Framework【第三篇】认证、权限、限制访问频率

    一、认证

    认证请求头

    views.py
    #!/usr/bin/env python
    # -*- coding:utf-8 -*-
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from rest_framework.authentication import BaseAuthentication
    from rest_framework.permissions import BasePermission
    
    from rest_framework.request import Request
    from rest_framework import exceptions
    
    token_list = [
        'sfsfss123kuf3j123',
        'asijnfowerkkf9812',
    ]
    
    
    class TestAuthentication(BaseAuthentication):
        def authenticate(self, request):
            """
            用户认证,如果验证成功后返回元组: (用户,用户Token)
            :param request: 
            :return: 
                None,表示跳过该验证;
                    如果跳过了所有认证,默认用户和Token和使用配置文件进行设置
                    self._authenticator = None
                    if api_settings.UNAUTHENTICATED_USER:
                        self.user = api_settings.UNAUTHENTICATED_USER() # 默认值为:匿名用户
                    else:
                        self.user = None
            
                    if api_settings.UNAUTHENTICATED_TOKEN:
                        self.auth = api_settings.UNAUTHENTICATED_TOKEN()# 默认值为:None
                    else:
                        self.auth = None
                (user,token)表示验证通过并设置用户名和Token;
                AuthenticationFailed异常
            """
            val = request.query_params.get('token')
            if val not in token_list:
                raise exceptions.AuthenticationFailed("用户认证失败")
    
            return ('登录用户', '用户token')
    
        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 TestPermission(BasePermission):
        message = "权限验证失败"
    
        def has_permission(self, request, view):
            """
            判断是否有权限访问当前请求
            Return `True` if permission is granted, `False` otherwise.
            :param request: 
            :param view: 
            :return: True有权限;False无权限
            """
            if request.user == "管理员":
                return True
    
        # GenericAPIView中get_object时调用
        def has_object_permission(self, request, view, obj):
            """
            视图继承GenericAPIView,并在其中使用get_object时获取对象时,触发单独对象权限验证
            Return `True` if permission is granted, `False` otherwise.
            :param request: 
            :param view: 
            :param obj: 
            :return: True有权限;False无权限
            """
            if request.user == "管理员":
                return True
    
    
    class TestView(APIView):
        # 认证的动作是由request.user触发
        authentication_classes = [TestAuthentication, ]
    
        # 权限
        # 循环执行所有的权限
        permission_classes = [TestPermission, ]
    
        def get(self, request, *args, **kwargs):
            # self.dispatch
            print(request.user)
            print(request.auth)
            return Response('GET请求,响应内容')
    
        def post(self, request, *args, **kwargs):
            return Response('POST请求,响应内容')
    
        def put(self, request, *args, **kwargs):
            return Response('PUT请求,响应内容')
    

      

    自定义认证功能
    class MyAuthtication(BasicAuthentication):
        def authenticate(self, request):
            token = request.query_params.get('token')  #注意是没有GET的,用query_params表示
            if token == 'zxxzzxzc':
                return ('uuuuuu','afsdsgdf') #返回user,auth
            # raise AuthenticationFailed('认证错误')  #只要抛出认证错误这样的异常就会去执行下面的函数
            raise APIException('认证错误')
        def authenticate_header(self, request):  #认证不成功的时候执行
            return 'Basic reala="api"'
    
    class UserView(APIView):
        authentication_classes = [MyAuthtication,]
        def get(self,request,*args,**kwargs):
            print(request.user)
            print(request.auth)
            return Response('用户列表')

     

    二、权限

    1、需求:Host是匿名用户和用户都能访问  #匿名用户的request.user = none;User只有注册用户能访问

    urls.py
    from app03 import views
    from django.conf.urls import url
    urlpatterns = [
        # django rest framework
        url('^auth/', views.AuthView.as_view()),
        url(r'^hosts/', views.HostView.as_view()),
        url(r'^users/', views.UsersView.as_view()),
        url(r'^salary/', views.SalaryView.as_view()),
    ]
    

      

    views.py
    from django.shortcuts import render
    from rest_framework.views import APIView  #继承的view
    from rest_framework.response import  Response #友好的返回
    from rest_framework.authentication import BaseAuthentication   #认证的类
    from rest_framework.authentication import BasicAuthentication
    from app01 import models
    from rest_framework import  exceptions
    from rest_framework.permissions import AllowAny   #权限在这个类里面
    from rest_framework.throttling import BaseThrottle,SimpleRateThrottle
    # Create your views here.
    # +++++++++++++++认证类和权限类========================
    class MyAuthentication(BaseAuthentication):
        def authenticate(self, request):
            token = request.query_params.get('token')
            obj = models.UserInfo.objects.filter(token=token).first()
            if obj :  #如果认证成功,返回用户名和auth
                return (obj.username,obj)
            return None  #如果没有认证成功就不处理,进行下一步
    
        def authenticate_header(self, request):
            pass
    
    class MyPermission(object):
        message = '无权访问'
        def has_permission(self,request,view):  #has_permission里面的self是view视图对象
            if request.user:
                return True  #如果不是匿名用户就说明有权限
            return False  #否则无权限
    
    class AdminPermission(object):
        message = '无权访问'
        def has_permission(self, request, view):  # has_permission里面的self是view视图对象
            if request.user=='haiyun':
                return True  # 返回True表示有权限
            return False #返回False表示无权限
    
    # +++++++++++++++++++++++++++
    class AuthView(APIView):
        authentication_classes = []  #认证页面不需要认证
    
        def get(self,request):
            self.dispatch
            return '认证列表'
    
    class HostView(APIView):
        '''需求:
              Host是匿名用户和用户都能访问  #匿名用户的request.user = none
              User只有注册用户能访问
        '''
        authentication_classes = [MyAuthentication,]
        permission_classes = []  #都能访问就没必要设置权限了
        def get(self,request):
            print(request.user)
            print(request.auth)
            return Response('主机列表')
    
    class UsersView(APIView):
        '''用户能访问,request.user里面有值'''
        authentication_classes = [MyAuthentication,]
        permission_classes = [MyPermission,]
        def get(self,request):
            print(request.user,'111111111')
            return Response('用户列表')
    
        def permission_denied(self, request, message=None):
            """
            If request is not permitted, determine what kind of exception to raise.
            """
            if request.authenticators and not request.successful_authenticator:
                '''如果没有通过认证,并且权限中return False了,就会报下面的这个异常了'''
                raise exceptions.NotAuthenticated(detail='无权访问')
            raise exceptions.PermissionDenied(detail=message)
    

      

    认证和权限配合使用
    class SalaryView(APIView):
        '''用户能访问'''
        message ='无权访问'
        authentication_classes = [MyAuthentication,]  #验证是不是用户
        permission_classes = [MyPermission,AdminPermission,] #再看用户有没有权限,如果有权限在判断有没有管理员的权限
        def get(self,request):
            return Response('薪资列表')
    
        def permission_denied(self, request, message=None):
            """
            If request is not permitted, determine what kind of exception to raise.
            """
            if request.authenticators and not request.successful_authenticator:
                '''如果没有通过认证,并且权限中return False了,就会报下面的这个异常了'''
                raise exceptions.NotAuthenticated(detail='无权访问')
            raise exceptions.PermissionDenied(detail=message)
    

      

    如果遇上这样的,还可以自定制,参考源码

        def check_permissions(self, request):
            """
            Check if the request should be permitted.
            Raises an appropriate exception if the request is not permitted.
            """
            for permission in self.get_permissions():
                #循环每一个permission对象,调用has_permission
                #如果False,则抛出异常
                #True 说明有权访问
                if not permission.has_permission(request, self):
                    self.permission_denied(
                        request, message=getattr(permission, 'message', None)
                    )
        def permission_denied(self, request, message=None):
            """
            If request is not permitted, determine what kind of exception to raise.
            """
            if request.authenticators and not request.successful_authenticator:
                '''如果没有通过认证,并且权限中return False了,就会报下面的这个异常了'''
                raise exceptions.NotAuthenticated()
            raise exceptions.PermissionDenied(detail=message)

    那么我们可以重写permission_denied这个方法,如下:

    views.py
    class UsersView(APIView):
        '''用户能访问,request.user里面有值'''
        authentication_classes = [MyAuthentication,]
        permission_classes = [MyPermission,]
        def get(self,request):
            return Response('用户列表')
    
        def permission_denied(self, request, message=None):
            """
            If request is not permitted, determine what kind of exception to raise.
            """
            if request.authenticators and not request.successful_authenticator:
                '''如果没有通过认证,并且权限中return False了,就会报下面的这个异常了'''
                raise exceptions.NotAuthenticated(detail='无权访问')
            raise exceptions.PermissionDenied(detail=message)
    

      

    2. 全局使用

    上述操作中均是对单独视图进行特殊配置,如果想要对全局进行配置,则需要再配置文件中写入即可。

    settings.py
    REST_FRAMEWORK = {
        'UNAUTHENTICATED_USER': None,
        'UNAUTHENTICATED_TOKEN': None,  #将匿名用户设置为None
        "DEFAULT_AUTHENTICATION_CLASSES": [
            "app01.utils.MyAuthentication",
        ],
        'DEFAULT_PERMISSION_CLASSES':[
            "app03.utils.MyPermission",#设置路径,
        ]
    }
    

      

    Views.py
    class AuthView(APIView):
        authentication_classes = []  #认证页面不需要认证
    
        def get(self,request):
            self.dispatch
            return '认证列表'
    
    class HostView(APIView):
        '''需求:
              Host是匿名用户和用户都能访问  #匿名用户的request.user = none
              User只有注册用户能访问
        '''
        authentication_classes = [MyAuthentication,]
        permission_classes = []  #都能访问就没必要设置权限了
        def get(self,request):
            print(request.user)
            print(request.auth)
            return Response('主机列表')
    
    class UsersView(APIView):
        '''用户能访问,request.user里面有值'''
        authentication_classes = [MyAuthentication,]
        permission_classes = [MyPermission,]
        def get(self,request):
            print(request.user,'111111111')
            return Response('用户列表')
    
        def permission_denied(self, request, message=None):
            """
            If request is not permitted, determine what kind of exception to raise.
            """
            if request.authenticators and not request.successful_authenticator:
                '''如果没有通过认证,并且权限中return False了,就会报下面的这个异常了'''
                raise exceptions.NotAuthenticated(detail='无权访问')
            raise exceptions.PermissionDenied(detail=message)
    
    
    class SalaryView(APIView):
        '''用户能访问'''
        message ='无权访问'
        authentication_classes = [MyAuthentication,]  #验证是不是用户
        permission_classes = [MyPermission,AdminPermission,] #再看用户有没有权限,如果有权限在判断有没有管理员的权限
        def get(self,request):
            return Response('薪资列表')
    
        def permission_denied(self, request, message=None):
            """
            If request is not permitted, determine what kind of exception to raise.
            """
            if request.authenticators and not request.successful_authenticator:
                '''如果没有通过认证,并且权限中return False了,就会报下面的这个异常了'''
                raise exceptions.NotAuthenticated(detail='无权访问')
            raise exceptions.PermissionDenied(detail=message)
    

      

    三、限流

    1、为什么要限流呢?  

    答:防爬

    2、限制访问频率源码分析

    self.check_throttles(request)
    self.check_throttles(request)
    check_throttles
    def check_throttles(self, request):
            """
            Check if request should be throttled.
            Raises an appropriate exception if the request is throttled.
            """
            for throttle in self.get_throttles():
                #循环每一个throttle对象,执行allow_request方法
                # allow_request:
                    #返回False,说明限制访问频率
                    #返回True,说明不限制,通行
                if not throttle.allow_request(request, self):
                    self.throttled(request, throttle.wait())
                    #throttle.wait()表示还要等多少秒就能访问了
    get_throttles
    def get_throttles(self):
            """
            Instantiates and returns the list of throttles that this view uses.
            """
            #返回对象
            return [throttle() for throttle in self.throttle_classes]
    找到类,可自定制类throttle_classes
    throttle_classes = api_settings.DEFAULT_THROTTLE_CLASSES
    BaseThrottle
    class BaseThrottle(object):
        """
        Rate throttling of requests.
        """
    
        def allow_request(self, request, view):
            """
            Return `True` if the request should be allowed, `False` otherwise.
            """
            raise NotImplementedError('.allow_request() must be overridden')
    
        def get_ident(self, request):
            """
            Identify the machine making the request by parsing HTTP_X_FORWARDED_FOR
            if present and number of proxies is > 0. If not use all of
            HTTP_X_FORWARDED_FOR if it is available, if not use REMOTE_ADDR.
            """
            xff = request.META.get('HTTP_X_FORWARDED_FOR')
            remote_addr = request.META.get('REMOTE_ADDR')
            num_proxies = api_settings.NUM_PROXIES
    
            if num_proxies is not None:
                if num_proxies == 0 or xff is None:
                    return remote_addr
                addrs = xff.split(',')
                client_addr = addrs[-min(num_proxies, len(addrs))]
                return client_addr.strip()
    
            return ''.join(xff.split()) if xff else remote_addr
    
        def wait(self):
            """
            Optionally, return a recommended number of seconds to wait before
            the next request.
            """
            return None
    也可以重写allow_request方法
     
    可自定制返回的错误信息throttled
    def throttled(self, request, wait):
            """
            If request is throttled, determine what kind of exception to raise.
            """
            raise exceptions.Throttled(wait)
    raise exceptions.Throttled(wait)错误信息详情
    class Throttled(APIException):
        status_code = status.HTTP_429_TOO_MANY_REQUESTS
        default_detail = _('Request was throttled.')
        extra_detail_singular = 'Expected available in {wait} second.'
        extra_detail_plural = 'Expected available in {wait} seconds.'
        default_code = 'throttled'
    
        def __init__(self, wait=None, detail=None, code=None):
            if detail is None:
                detail = force_text(self.default_detail)
            if wait is not None:
                wait = math.ceil(wait)
                detail = ' '.join((
                    detail,
                    force_text(ungettext(self.extra_detail_singular.format(wait=wait),
                                         self.extra_detail_plural.format(wait=wait),
                                         wait))))
            self.wait = wait
            super(Throttled, self).__init__(detail, code)
    

      

     下面来看看最简单的从源码中分析的示例,这只是举例说明了一下

    urls.py
    from django.conf.urls import url
    from app04 import views
    urlpatterns = [
        url('limit/',views.LimitView.as_view()),
    
    ]
    views.py
    from django.shortcuts import render
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from rest_framework import exceptions
    # from rest_framewor import
    # Create your views here.
    class MyThrottle(object):
        def allow_request(self,request,view):
            #返回False,限制
            #返回True,不限制
            pass
        def wait(self):
            return 1000
    
    
    class LimitView(APIView):
        authentication_classes = []  #不让认证用户
        permission_classes = []  #不让验证权限
        throttle_classes = [MyThrottle, ]
        def get(self,request):
            # self.dispatch
            return Response('控制访问频率示例')
    
        def throttled(self, request, wait):
            '''可定制方法设置中文错误'''
            # raise exceptions.Throttled(wait)
            class MyThrottle(exceptions.Throttled):
                default_detail = '请求被限制'
                extra_detail_singular = 'Expected available in {wait} second.'
                extra_detail_plural = 'Expected available in {wait} seconds.'
                default_code = '还需要再等{wait}秒'
            raise MyThrottle(wait)
    

      

    3、需求:对匿名用户进行限制,每个用户一分钟允许访问10次(只针对用户来说)

    a、基于用户IP限制访问频率

    流程分析:

    • 先获取用户信息,如果是匿名用户,获取IP。如果不是匿名用户就可以获取用户名。
    • 获取匿名用户IP,在request里面获取,比如IP= 1.1.1.1。
    • 吧获取到的IP添加到到recode字典里面,需要在添加之前先限制一下。
    • 如果时间间隔大于60秒,说明时间久远了,就把那个时间给剔除 了pop。在timelist列表里面现在留的是有效的访问时间段。
    • 然后判断他的访问次数超过了10次没有,如果超过了时间就return False。
    • 美中不足的是时间是固定的,我们改变他为动态的:列表里面最开始进来的时间和当前的时间进行比较,看需要等多久。

    具体实现:

    views初级版本
    from django.shortcuts import render
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from rest_framework import exceptions
    from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
    import time
    # Create your views here.
    RECORD = {}
    class MyThrottle(BaseThrottle):
    
        def allow_request(self,request,view):
            '''对匿名用户进行限制,每个用户一分钟访问10次 '''
            ctime = time.time()
            ip = '1.1.1.1'
            if ip not in RECORD:
                RECORD[ip] = [ctime]
            else:
                #[152042123,15204212,3152042,123152042123]
                time_list = RECORD[ip]  #获取ip里面的值
                while True:
                    val = time_list[-1]#取出最后一个时间,也就是访问最早的时间
                    if (ctime-60)>val:  #吧时间大于60秒的给剔除了
                        time_list.pop()
                    #剔除了之后timelist里面就是有效的时间了,在进行判断他的访问次数是不是超过10次
                    else:
                        break
                if len(time_list) >10:
                    return False        # 返回False,限制
                time_list.insert(0, ctime)
            return True   #返回True,不限制
    
        def wait(self):
            ctime = time.time()
            first_in_time = RECORD['1.1.1.1'][-1]
            wt = 60-(ctime-first_in_time)
            return wt
    
    
    class LimitView(APIView):
        authentication_classes = []  #不让认证用户
        permission_classes = []  #不让验证权限
        throttle_classes = [MyThrottle, ]
        def get(self,request):
            # self.dispatch
            return Response('控制访问频率示例')
    
        def throttled(self, request, wait):
            '''可定制方法设置中文错误'''
            # raise exceptions.Throttled(wait)
            class MyThrottle(exceptions.Throttled):
                default_detail = '请求被限制'
                extra_detail_singular = 'Expected available in {wait} second.'
                extra_detail_plural = 'Expected available in {wait} seconds.'
                default_code = '还需要再等{wait}秒'
            raise MyThrottle(wait)
     
    稍微做了改动
    # from django.shortcuts import render
    # from rest_framework.views import APIView
    # from rest_framework.response import Response
    # from rest_framework import exceptions
    # from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
    # import time
    # # Create your views here.
    # RECORD = {}
    # class MyThrottle(BaseThrottle):
    #
    #     def allow_request(self,request,view):
    #         '''对匿名用户进行限制,每个用户一分钟访问10次 '''
    #         ctime = time.time()
    #         ip = '1.1.1.1'
    #         if ip not in RECORD:
    #             RECORD[ip] = [ctime]
    #         else:
    #             #[152042123,15204212,3152042,123152042123]
    #             time_list = RECORD[ip]  #获取ip里面的值
    #             while True:
    #                 val = time_list[-1]#取出最后一个时间,也就是访问最早的时间
    #                 if (ctime-60)>val:  #吧时间大于60秒的给剔除了
    #                     time_list.pop()
    #                 #剔除了之后timelist里面就是有效的时间了,在进行判断他的访问次数是不是超过10次
    #                 else:
    #                     break
    #             if len(time_list) >10:
    #                 return False        # 返回False,限制
    #             time_list.insert(0, ctime)
    #         return True   #返回True,不限制
    #
    #     def wait(self):
    #         ctime = time.time()
    #         first_in_time = RECORD['1.1.1.1'][-1]
    #         wt = 60-(ctime-first_in_time)
    #         return wt
    #
    #
    # class LimitView(APIView):
    #     authentication_classes = []  #不让认证用户
    #     permission_classes = []  #不让验证权限
    #     throttle_classes = [MyThrottle, ]
    #     def get(self,request):
    #         # self.dispatch
    #         return Response('控制访问频率示例')
    #
    #     def throttled(self, request, wait):
    #         '''可定制方法设置中文错误'''
    #         # raise exceptions.Throttled(wait)
    #         class MyThrottle(exceptions.Throttled):
    #             default_detail = '请求被限制'
    #             extra_detail_singular = 'Expected available in {wait} second.'
    #             extra_detail_plural = 'Expected available in {wait} seconds.'
    #             default_code = '还需要再等{wait}秒'
    #         raise MyThrottle(wait)
    
    
    
    from django.shortcuts import render
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from rest_framework import exceptions
    from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
    import time
    # Create your views here.
    RECORD = {}
    class MyThrottle(BaseThrottle):
    
        def allow_request(self,request,view):
            '''对匿名用户进行限制,每个用户一分钟访问10次 '''
            ctime = time.time()
            self.ip =self.get_ident(request)
            if self.ip not in RECORD:
                RECORD[self.ip] = [ctime]
            else:
                #[152042123,15204212,3152042,123152042123]
                time_list = RECORD[self.ip]  #获取ip里面的值
                while True:
                    val = time_list[-1]#取出最后一个时间,也就是访问最早的时间
                    if (ctime-60)>val:  #吧时间大于60秒的给剔除了
                        time_list.pop()
                    #剔除了之后timelist里面就是有效的时间了,在进行判断他的访问次数是不是超过10次
                    else:
                        break
                if len(time_list) >10:
                    return False        # 返回False,限制
                time_list.insert(0, ctime)
            return True   #返回True,不限制
    
        def wait(self):
            ctime = time.time()
            first_in_time = RECORD[self.ip][-1]
            wt = 60-(ctime-first_in_time)
            return wt
    
    
    class LimitView(APIView):
        authentication_classes = []  #不让认证用户
        permission_classes = []  #不让验证权限
        throttle_classes = [MyThrottle, ]
        def get(self,request):
            # self.dispatch
            return Response('控制访问频率示例')
    
        def throttled(self, request, wait):
            '''可定制方法设置中文错误'''
            # raise exceptions.Throttled(wait)
            class MyThrottle(exceptions.Throttled):
                default_detail = '请求被限制'
                extra_detail_singular = 'Expected available in {wait} second.'
                extra_detail_plural = 'Expected available in {wait} seconds.'
                default_code = '还需要再等{wait}秒'
            raise MyThrottle(wait)
    

      

    b、用resetframework内部的限制访问频率(利于Django缓存)

     源码分析:

    from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
    BaseThrottle相当于一个抽象类
    class BaseThrottle(object):
        """
        Rate throttling of requests.
        """
    
        def allow_request(self, request, view):
            """
            Return `True` if the request should be allowed, `False` otherwise.
            """
            raise NotImplementedError('.allow_request() must be overridden')
    
        def get_ident(self, request):  #唯一标识
            """
            Identify the machine making the request by parsing HTTP_X_FORWARDED_FOR
            if present and number of proxies is > 0. If not use all of
            HTTP_X_FORWARDED_FOR if it is available, if not use REMOTE_ADDR.
            """
            xff = request.META.get('HTTP_X_FORWARDED_FOR')
            remote_addr = request.META.get('REMOTE_ADDR') #获取IP等
            num_proxies = api_settings.NUM_PROXIES
    
            if num_proxies is not None:
                if num_proxies == 0 or xff is None:
                    return remote_addr
                addrs = xff.split(',')
                client_addr = addrs[-min(num_proxies, len(addrs))]
                return client_addr.strip()
    
            return ''.join(xff.split()) if xff else remote_addr
    
        def wait(self):
            """
            Optionally, return a recommended number of seconds to wait before
            the next request.
            """
            return None
    
    SimpleRateThrottle
    class SimpleRateThrottle(BaseThrottle):
        """
        一个简单的缓存实现,只需要` get_cache_key() `。被覆盖。
        速率(请求/秒)是由视图上的“速率”属性设置的。类。该属性是一个字符串的形式number_of_requests /期。
        周期应该是:(的),“秒”,“M”,“min”,“h”,“小时”,“D”,“一天”。
        以前用于节流的请求信息存储在高速缓存中。
        A simple cache implementation, that only requires `.get_cache_key()`
        to be overridden.
    
        The rate (requests / seconds) is set by a `rate` attribute on the View
        class.  The attribute is a string of the form 'number_of_requests/period'.
    
        Period should be one of: ('s', 'sec', 'm', 'min', 'h', 'hour', 'd', 'day')
    
        Previous request information used for throttling is stored in the cache.
        """
        cache = default_cache
        timer = time.time
        cache_format = 'throttle_%(scope)s_%(ident)s'
        scope = None
        THROTTLE_RATES = api_settings.DEFAULT_THROTTLE_RATES
    
        def __init__(self):
            if not getattr(self, 'rate', None):
                self.rate = self.get_rate()
            self.num_requests, self.duration = self.parse_rate(self.rate)
    
        def get_cache_key(self, request, view):#这个相当于是一个半成品,我们可以来补充它
            """
            Should return a unique cache-key which can be used for throttling.
            Must be overridden.
    
            May return `None` if the request should not be throttled.
            """
            raise NotImplementedError('.get_cache_key() must be overridden')
    
        def get_rate(self):
            """
            Determine the string representation of the allowed request rate.
            """
            if not getattr(self, 'scope', None):
                msg = ("You must set either `.scope` or `.rate` for '%s' throttle" %
                       self.__class__.__name__)
                raise ImproperlyConfigured(msg)
    
            try:
                return self.THROTTLE_RATES[self.scope]
            except KeyError:
                msg = "No default throttle rate set for '%s' scope" % self.scope
                raise ImproperlyConfigured(msg)
    
        def parse_rate(self, rate):
            """
            Given the request rate string, return a two tuple of:
            <allowed number of requests>, <period of time in seconds>
            """
            if rate is None:
                return (None, None)
            num, period = rate.split('/')
            num_requests = int(num)
            duration = {'s': 1, 'm': 60, 'h': 3600, 'd': 86400}[period[0]]
            return (num_requests, duration)
    
        #1、一进来会先执行他,
        def allow_request(self, request, view):
            """
            Implement the check to see if the request should be throttled.
    
            On success calls `throttle_success`.
            On failure calls `throttle_failure`.
            """
            if self.rate is None:
                return True
    
            self.key = self.get_cache_key(request, view)  #2、执行get_cache_key,这里的self.key就相当于我们举例ip
            if self.key is None:
                return True
    
            self.history = self.cache.get(self.key, [])  #3、得到的key,默认是一个列表,赋值给了self.history,
                                                            # 这时候self.history就是每一个ip对应的访问记录
            self.now = self.timer()
    
            # Drop any requests from the history which have now passed the
            # throttle duration
            while self.history and self.history[-1] <= self.now - self.duration:
                self.history.pop()
            if len(self.history) >= self.num_requests:
                return self.throttle_failure()
            return self.throttle_success()
    
        def throttle_success(self):
            """
            Inserts the current request's timestamp along with the key
            into the cache.
            """
            self.history.insert(0, self.now)
            self.cache.set(self.key, self.history, self.duration)
            return True
    
        def throttle_failure(self):
            """
            Called when a request to the API has failed due to throttling.
            """
            return False
    
        def wait(self):
            """
            Returns the recommended next request time in seconds.
            """
            if self.history:
                remaining_duration = self.duration - (self.now - self.history[-1])
            else:
                remaining_duration = self.duration
    
            available_requests = self.num_requests - len(self.history) + 1
            if available_requests <= 0:
                return None
    
            return remaining_duration / float(available_requests)
    

      

    请求一进来会先执行SimpleRateThrottle这个类的构造方法

    __init__
    def __init__(self):
            if not getattr(self, 'rate', None):
                self.rate = self.get_rate()  #点进去看到需要些一个scope  ,2/m
            self.num_requests, self.duration = self.parse_rate(self.rate)
    

      

    get_rate
    def get_rate(self):
            """
            Determine the string representation of the allowed request rate.
            """
            if not getattr(self, 'scope', None):  #检测必须有scope,没有就报错了
                msg = ("You must set either `.scope` or `.rate` for '%s' throttle" %
                       self.__class__.__name__)
                raise ImproperlyConfigured(msg)
    
            try:
                return self.THROTTLE_RATES[self.scope]
            except KeyError:
                msg = "No default throttle rate set for '%s' scope" % self.scope
                raise ImproperlyConfigured(msg)
    

      

    parse_rate
    def parse_rate(self, rate):
            """
            Given the request rate string, return a two tuple of:
            <allowed number of requests>, <period of time in seconds>
            """
            if rate is None:
                return (None, None)
            num, period = rate.split('/')
            num_requests = int(num)
            duration = {'s': 1, 'm': 60, 'h': 3600, 'd': 86400}[period[0]]
            return (num_requests, duration)
    

      

    allow_request
    #2、接下来会先执行他,
        def allow_request(self, request, view):
            """
            Implement the check to see if the request should be throttled.
    
            On success calls `throttle_success`.
            On failure calls `throttle_failure`.
            """
            if self.rate is None:
                return True
    
            self.key = self.get_cache_key(request, view)  #2、执行get_cache_key,这里的self.key就相当于我们举例ip
            if self.key is None:
                return True  #不限制
            # [114521212,11452121211,45212121145,21212114,521212]
            self.history = self.cache.get(self.key, [])  #3、得到的key,默认是一个列表,赋值给了self.history,
                                                            # 这时候self.history就是每一个ip对应的访问记录
            self.now = self.timer()
    
            # Drop any requests from the history which have now passed the
            # throttle duration
            while self.history and self.history[-1] <= self.now - self.duration:
                self.history.pop()
            if len(self.history) >= self.num_requests:
                return self.throttle_failure()
            return self.throttle_success()
    

      

    wait
    def wait(self):
            """
            Returns the recommended next request time in seconds.
            """
            if self.history:
                remaining_duration = self.duration - (self.now - self.history[-1])
            else:
                remaining_duration = self.duration
    
            available_requests = self.num_requests - len(self.history) + 1
            if available_requests <= 0:
                return None
    
            return remaining_duration / float(available_requests)
    

      

    代码实现:

    views.py
    ###########用resetframework内部的限制访问频率##############
    class MySimpleRateThrottle(SimpleRateThrottle):
        scope = 'xxx'
        def get_cache_key(self, request, view):
            return self.get_ident(request)  #返回唯一标识IP
    
    class LimitView(APIView):
        authentication_classes = []  #不让认证用户
        permission_classes = []  #不让验证权限
        throttle_classes = [MySimpleRateThrottle, ]
        def get(self,request):
            # self.dispatch
            return Response('控制访问频率示例')
    
        def throttled(self, request, wait):
            '''可定制方法设置中文错误'''
            # raise exceptions.Throttled(wait)
            class MyThrottle(exceptions.Throttled):
                default_detail = '请求被限制'
                extra_detail_singular = 'Expected available in {wait} second.'
                extra_detail_plural = 'Expected available in {wait} seconds.'
                default_code = '还需要再等{wait}秒'
            raise MyThrottle(wait)
    

      

    记得在settings里面配置

    settings.py
    REST_FRAMEWORK = {
        'UNAUTHENTICATED_USER': None,
        'UNAUTHENTICATED_TOKEN': None,  #将匿名用户设置为None
        "DEFAULT_AUTHENTICATION_CLASSES": [
            "app01.utils.MyAuthentication",
        ],
        'DEFAULT_PERMISSION_CLASSES':[
            # "app03.utils.MyPermission",#设置路径,
        ],
        'DEFAULT_THROTTLE_RATES':{
            'xxx':'2/minute'  #2分钟
        }
    }
    
    #缓存:放在文件
    CACHES = {
        'default': {
            'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
            'LOCATION': 'cache',   #文件路径
        }
    }
    

      

    4、对匿名用户进行限制,每个用户1分钟允许访问5次,对于登录的普通用户1分钟访问10次,VIP用户一分钟访问20次

    • 比如首页可以匿名访问
    • #先认证,只有认证了才知道是不是匿名的,
    • #权限登录成功之后才能访问, ,index页面就不需要权限了
    • If request.user  #判断登录了没有
    urls.py
    from django.contrib import admin
    
    from django.conf.urls import url, include
    from app05 import views
    
    urlpatterns = [
        url('index/',views.IndexView.as_view()),
        url('manage/',views.ManageView.as_view()),
    ]
    views.py
    from django.shortcuts import render
    from rest_framework.views import APIView
    from rest_framework.response import Response
    from rest_framework.authentication import BaseAuthentication  #认证需要
    from rest_framework.throttling import BaseThrottle,SimpleRateThrottle #限流处理
    from rest_framework.permissions import BasePermission
    from rest_framework import exceptions
    from app01 import models
    # Create your views here.
    ###############3##认证#####################
    class MyAuthentcate(BaseAuthentication):
        '''检查用户是否存在,如果存在就返回user和auth,如果没有就返回'''
        def authenticate(self, request):
            token = request.query_params.get('token')
            obj = models.UserInfo.objects.filter(token=token).first()
            if obj:
                return (obj.username,obj.token)
            return None  #表示我不处理
    
    ##################权限#####################
    class MyPermission(BasePermission):
        message='无权访问'
        def has_permission(self, request, view):
            if request.user:
                return True  #true表示有权限
            return False  #false表示无权限
    
    class AdminPermission(BasePermission):
        message = '无权访问'
    
        def has_permission(self, request, view):
            if request.user=='haiyan':
                return True  # true表示有权限
            return False  # false表示无权限
    
    ############3#####限流##################3##
    class AnonThrottle(SimpleRateThrottle):
        scope = 'wdp_anon'  #相当于设置了最大的访问次数和时间
        def get_cache_key(self, request, view):
            if request.user:
                return None  #返回None表示我不限制,登录用户我不管
            #匿名用户
            return self.get_ident(request)  #返回一个唯一标识IP
    
    class UserThrottle(SimpleRateThrottle):
        scope = 'wdp_user'
        def get_cache_key(self, request, view):
            #登录用户
            if request.user:
                return request.user
            return None  #返回NOne表示匿名用户我不管
    
    
    ##################视图#####################
    #首页支持匿名访问,
    #无需要登录就可以访问
    class IndexView(APIView):
        authentication_classes = [MyAuthentcate,]   #认证判断他是不是匿名用户
        permission_classes = []   #一般主页就不需要权限验证了
        throttle_classes = [AnonThrottle,UserThrottle,]  #对匿名用户和普通用户的访问限制
    
        def get(self,request):
            # self.dispatch
            return Response('访问首页')
    
        def throttled(self, request, wait):
            '''可定制方法设置中文错误'''
    
            # raise exceptions.Throttled(wait)
            class MyThrottle(exceptions.Throttled):
                default_detail = '请求被限制'
                extra_detail_singular = 'Expected available in {wait} second.'
                extra_detail_plural = 'Expected available in {wait} seconds.'
                default_code = '还需要再等{wait}秒'
    
            raise MyThrottle(wait)
    
    #需登录就可以访问
    class ManageView(APIView):
        authentication_classes = [MyAuthentcate, ]  # 认证判断他是不是匿名用户
        permission_classes = [MyPermission,]  # 一般主页就不需要权限验证了
        throttle_classes = [AnonThrottle, UserThrottle, ]  # 对匿名用户和普通用户的访问限制
    
        def get(self, request):
            # self.dispatch
            return Response('管理人员访问页面')
    
        def throttled(self, request, wait):
            '''可定制方法设置中文错误'''
    
            # raise exceptions.Throttled(wait)
            class MyThrottle(exceptions.Throttled):
                default_detail = '请求被限制'
                extra_detail_singular = 'Expected available in {wait} second.'
                extra_detail_plural = 'Expected available in {wait} seconds.'
                default_code = '还需要再等{wait}秒'
    
            raise MyThrottle(wait)

     

    四、总结

    1、认证:就是检查用户是否存在;如果存在返回(request.user,request.auth);不存在request.user/request.auth=None

     2、权限:进行职责的划分

    3、限制访问频率

    认证
        - 类:authenticate/authenticate_header ##验证不成功的时候执行的
        - 返回值:
            - return None,
            - return (user,auth),
            - raise 异常
        - 配置:
            - 视图:
                class IndexView(APIView):
                    authentication_classes = [MyAuthentication,]
            - 全局:
                REST_FRAMEWORK = {
                        'UNAUTHENTICATED_USER': None,
                        'UNAUTHENTICATED_TOKEN': None,
                        "DEFAULT_AUTHENTICATION_CLASSES": [
                            # "app02.utils.MyAuthentication",
                        ],
                }
    
    权限 
        - 类:has_permission/has_object_permission
        - 返回值: 
            - True、#有权限
            - False、#无权限
            - exceptions.PermissionDenied(detail="错误信息")  #异常自己随意,想抛就抛,错误信息自己指定
        - 配置:
            - 视图:
                class IndexView(APIView):
                    permission_classes = [MyPermission,]
            - 全局:
                REST_FRAMEWORK = {
                        "DEFAULT_PERMISSION_CLASSES": [
                            # "app02.utils.MyAuthentication",
                        ],
                }
    限流
        - 类:allow_request/wait PS: scope = "wdp_user"
        - 返回值:
          return True、#不限制
          return False #限制 - 配置: - 视图: class IndexView(APIView): throttle_classes=[AnonThrottle,UserThrottle,] def get(self,request,*args,**kwargs): self.dispatch return Response('访问首页') - 全局 REST_FRAMEWORK = { "DEFAULT_THROTTLE_CLASSES":[ ], 'DEFAULT_THROTTLE_RATES':{ 'wdp_anon':'5/minute', 'wdp_user':'10/minute', } }
  • 相关阅读:
    STM32本学习笔记EXTI(外部中断)
    加速了土壤深根技术,建立了完善的技术体系,改变思维模式,引创造新的工作流程。。。
    2.大约QT数据库操作,简单的数据库连接操作,增删改查数据库,QSqlTableModel和QTableView,事务性操作,大约QItemDelegate 代理
    CentOS7下一个mysql安装
    【iOS】随机三角瓷砖布局算法
    [LeetCode]Pascal&#39;s Triangle
    APK 代码混淆
    动态规划最长的回文序列
    jQuery整理笔记2----jQuery选择整理
    POJ 3422 Kaka&#39;s Matrix Travels(费用流)
  • 原文地址:https://www.cnblogs.com/xiaohema/p/8456857.html
Copyright © 2011-2022 走看看