zoukankan      html  css  js  c++  java

  • Restful Framework （二）

    目录

    一、认证

    二、权限

    三、限制访问频率

    四、总结

    一、认证（补充的一个点）

    回到顶部

    认证请求头

     1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 from rest_framework.views import APIView
 4 from rest_framework.response import Response
 5 from rest_framework.authentication import BaseAuthentication
 6 from rest_framework.permissions import BasePermission
 7 
 8 from rest_framework.request import Request
 9 from rest_framework import exceptions
10 
11 token_list = [
12     'sfsfss123kuf3j123',
13     'asijnfowerkkf9812',
14 ]
15 
16 
17 class TestAuthentication(BaseAuthentication):
18     def authenticate(self, request):
19         """
20         用户认证，如果验证成功后返回元组： (用户,用户Token)
21         :param request: 
22         :return: 
23             None,表示跳过该验证；
24                 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
25                 self._authenticator = None
26                 if api_settings.UNAUTHENTICATED_USER:
27                     self.user = api_settings.UNAUTHENTICATED_USER() # 默认值为：匿名用户
28                 else:
29                     self.user = None
30         
31                 if api_settings.UNAUTHENTICATED_TOKEN:
32                     self.auth = api_settings.UNAUTHENTICATED_TOKEN()# 默认值为：None
33                 else:
34                     self.auth = None
35             (user,token)表示验证通过并设置用户名和Token；
36             AuthenticationFailed异常
37         """
38         val = request.query_params.get('token')
39         if val not in token_list:
40             raise exceptions.AuthenticationFailed("用户认证失败")
41 
42         return ('登录用户', '用户token')
43 
44     def authenticate_header(self, request):
45         """
46         Return a string to be used as the value of the `WWW-Authenticate`
47         header in a `401 Unauthenticated` response, or `None` if the
48         authentication scheme should return `403 Permission Denied` responses.
49         """
50         pass
51 
52 
53 class TestPermission(BasePermission):
54     message = "权限验证失败"
55 
56     def has_permission(self, request, view):
57         """
58         判断是否有权限访问当前请求
59         Return `True` if permission is granted, `False` otherwise.
60         :param request: 
61         :param view: 
62         :return: True有权限；False无权限
63         """
64         if request.user == "管理员":
65             return True
66 
67     # GenericAPIView中get_object时调用
68     def has_object_permission(self, request, view, obj):
69         """
70         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
71         Return `True` if permission is granted, `False` otherwise.
72         :param request: 
73         :param view: 
74         :param obj: 
75         :return: True有权限；False无权限
76         """
77         if request.user == "管理员":
78             return True
79 
80 
81 class TestView(APIView):
82     # 认证的动作是由request.user触发
83     authentication_classes = [TestAuthentication, ]
84 
85     # 权限
86     # 循环执行所有的权限
87     permission_classes = [TestPermission, ]
88 
89     def get(self, request, *args, **kwargs):
90         # self.dispatch
91         print(request.user)
92         print(request.auth)
93         return Response('GET请求，响应内容')
94 
95     def post(self, request, *args, **kwargs):
96         return Response('POST请求，响应内容')
97 
98     def put(self, request, *args, **kwargs):
99         return Response('PUT请求，响应内容')
    views.py
     1 #
 2 class MyAuthtication(BasicAuthentication):
 3     def authenticate(self, request):
 4         token = request.query_params.get('token')  #注意是没有GET的，用query_params表示
 5         if token == 'zxxzzxzc':
 6             return ('uuuuuu','afsdsgdf') #返回user，auth
 7         # 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
 8         raise APIException('认证错误')
 9     def authenticate_header(self, request):  #认证不成功的时候执行
10         return 'Basic reala="api"'
11 
12 class UserView(APIView):
13     authentication_classes = [MyAuthtication,]
14     def get(self,request,*args,**kwargs):
15         print(request.user)
16         print(request.auth)
17         return Response('用户列表')
    自定义认证功能

    二、权限

    回到顶部

    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

    1 from app03 import views
2 from django.conf.urls import url
3 urlpatterns = [
4     # django rest framework
5     url('^auth/', views.AuthView.as_view()),
6     url(r'^hosts/', views.HostView.as_view()),
7     url(r'^users/', views.UsersView.as_view()),
8     url(r'^salary/', views.SalaryView.as_view()),
9 ]
    urls.py
     1 from django.shortcuts import render
 2 from rest_framework.views import APIView  #继承的view
 3 from rest_framework.response import  Response #友好的返回
 4 from rest_framework.authentication import BaseAuthentication   #认证的类
 5 from rest_framework.authentication import BasicAuthentication
 6 from app01 import models
 7 from rest_framework import  exceptions
 8 from rest_framework.permissions import AllowAny   #权限在这个类里面
 9 from rest_framework.throttling import BaseThrottle,SimpleRateThrottle
10 # Create your views here.
11 # +++++++++++++++认证类和权限类========================
12 class MyAuthentication(BaseAuthentication):
13     def authenticate(self, request):
14         token = request.query_params.get('token')
15         obj = models.UserInfo.objects.filter(token=token).first()
16         if obj :  #如果认证成功，返回用户名和auth
17             return (obj.username,obj)
18         return None  #如果没有认证成功就不处理，进行下一步
19 
20     def authenticate_header(self, request):
21         pass
22 
23 class MyPermission(object):
24     message = '无权访问'
25     def has_permission(self,request,view):  #has_permission里面的self是view视图对象
26         if request.user:
27             return True  #如果不是匿名用户就说明有权限
28         return False  #否则无权限
29 
30 class AdminPermission(object):
31     message = '无权访问'
32     def has_permission(self, request, view):  # has_permission里面的self是view视图对象
33         if request.user=='haiyun':
34             return True  # 返回True表示有权限
35         return False #返回False表示无权限
36 
37 # +++++++++++++++++++++++++++
38 class AuthView(APIView):
39     authentication_classes = []  #认证页面不需要认证
40 
41     def get(self,request):
42         self.dispatch
43         return '认证列表'
44 
45 class HostView(APIView):
46     '''需求：
47           Host是匿名用户和用户都能访问  #匿名用户的request.user = none
48           User只有注册用户能访问
49     '''
50     authentication_classes = [MyAuthentication,]
51     permission_classes = []  #都能访问就没必要设置权限了
52     def get(self,request):
53         print(request.user)
54         print(request.auth)
55         return Response('主机列表')
56 
57 class UsersView(APIView):
58     '''用户能访问,request.user里面有值'''
59     authentication_classes = [MyAuthentication,]
60     permission_classes = [MyPermission,]
61     def get(self,request):
62         print(request.user,'111111111')
63         return Response('用户列表')
64 
65     def permission_denied(self, request, message=None):
66         """
67         If request is not permitted, determine what kind of exception to raise.
68         """
69         if request.authenticators and not request.successful_authenticator:
70             '''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'''
71             raise exceptions.NotAuthenticated(detail='无权访问')
72         raise exceptions.PermissionDenied(detail=message)
    views.py
     1 class SalaryView(APIView):
 2     '''用户能访问'''
 3     message ='无权访问'
 4     authentication_classes = [MyAuthentication,]  #验证是不是用户
 5     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
 6     def get(self,request):
 7         return Response('薪资列表')
 8 
 9     def permission_denied(self, request, message=None):
10         """
11         If request is not permitted, determine what kind of exception to raise.
12         """
13         if request.authenticators and not request.successful_authenticator:
14             '''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'''
15             raise exceptions.NotAuthenticated(detail='无权访问')
16         raise exceptions.PermissionDenied(detail=message)
    认证和权限配合使用

    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：

     1 class UsersView(APIView):
 2     '''用户能访问,request.user里面有值'''
 3     authentication_classes = [MyAuthentication,]
 4     permission_classes = [MyPermission,]
 5     def get(self,request):
 6         return Response('用户列表')
 7 
 8     def permission_denied(self, request, message=None):
 9         """
10         If request is not permitted, determine what kind of exception to raise.
11         """
12         if request.authenticators and not request.successful_authenticator:
13             '''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'''
14             raise exceptions.NotAuthenticated(detail='无权访问')
15         raise exceptions.PermissionDenied(detail=message)
    views.py

    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。

     1 REST_FRAMEWORK = {
 2     'UNAUTHENTICATED_USER': None,
 3     'UNAUTHENTICATED_TOKEN': None,  #将匿名用户设置为None
 4     "DEFAULT_AUTHENTICATION_CLASSES": [
 5         "app01.utils.MyAuthentication",
 6     ],
 7     'DEFAULT_PERMISSION_CLASSES':[
 8         "app03.utils.MyPermission",#设置路径，
 9     ]
10 }
    settings.py
     1 class AuthView(APIView):
 2     authentication_classes = []  #认证页面不需要认证
 3 
 4     def get(self,request):
 5         self.dispatch
 6         return '认证列表'
 7 
 8 class HostView(APIView):
 9     '''需求：
10           Host是匿名用户和用户都能访问  #匿名用户的request.user = none
11           User只有注册用户能访问
12     '''
13     authentication_classes = [MyAuthentication,]
14     permission_classes = []  #都能访问就没必要设置权限了
15     def get(self,request):
16         print(request.user)
17         print(request.auth)
18         return Response('主机列表')
19 
20 class UsersView(APIView):
21     '''用户能访问,request.user里面有值'''
22     authentication_classes = [MyAuthentication,]
23     permission_classes = [MyPermission,]
24     def get(self,request):
25         print(request.user,'111111111')
26         return Response('用户列表')
27 
28     def permission_denied(self, request, message=None):
29         """
30         If request is not permitted, determine what kind of exception to raise.
31         """
32         if request.authenticators and not request.successful_authenticator:
33             '''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'''
34             raise exceptions.NotAuthenticated(detail='无权访问')
35         raise exceptions.PermissionDenied(detail=message)
36 
37 
38 class SalaryView(APIView):
39     '''用户能访问'''
40     message ='无权访问'
41     authentication_classes = [MyAuthentication,]  #验证是不是用户
42     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
43     def get(self,request):
44         return Response('薪资列表')
45 
46     def permission_denied(self, request, message=None):
47         """
48         If request is not permitted, determine what kind of exception to raise.
49         """
50         if request.authenticators and not request.successful_authenticator:
51             '''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'''
52             raise exceptions.NotAuthenticated(detail='无权访问')
53         raise exceptions.PermissionDenied(detail=message)
    Views.py

    三、限流

    回到顶部

    1、为什么要限流呢?  

    答：防爬

    2、限制访问频率源码分析

    1  self.check_throttles(request)
    self.check_throttles(request)
     1     def check_throttles(self, request):
 2         """
 3         Check if request should be throttled.
 4         Raises an appropriate exception if the request is throttled.
 5         """
 6         for throttle in self.get_throttles():
 7             #循环每一个throttle对象，执行allow_request方法
 8             # allow_request:
 9                 #返回False，说明限制访问频率
10                 #返回True，说明不限制，通行
11             if not throttle.allow_request(request, self):
12                 self.throttled(request, throttle.wait())
13                 #throttle.wait()表示还要等多少秒就能访问了
    check_throttles
    1     def get_throttles(self):
2         """
3         Instantiates and returns the list of throttles that this view uses.
4         """
5         #返回对象
6         return [throttle() for throttle in self.throttle_classes]
    get_throttles
    1 throttle_classes = api_settings.DEFAULT_THROTTLE_CLASSES
    找到类，可自定制类throttle_classes
     1 class BaseThrottle(object):
 2     """
 3     Rate throttling of requests.
 4     """
 5 
 6     def allow_request(self, request, view):
 7         """
 8         Return `True` if the request should be allowed, `False` otherwise.
 9         """
10         raise NotImplementedError('.allow_request() must be overridden')
11 
12     def get_ident(self, request):
13         """
14         Identify the machine making the request by parsing HTTP_X_FORWARDED_FOR
15         if present and number of proxies is > 0. If not use all of
16         HTTP_X_FORWARDED_FOR if it is available, if not use REMOTE_ADDR.
17         """
18         xff = request.META.get('HTTP_X_FORWARDED_FOR')
19         remote_addr = request.META.get('REMOTE_ADDR')
20         num_proxies = api_settings.NUM_PROXIES
21 
22         if num_proxies is not None:
23             if num_proxies == 0 or xff is None:
24                 return remote_addr
25             addrs = xff.split(',')
26             client_addr = addrs[-min(num_proxies, len(addrs))]
27             return client_addr.strip()
28 
29         return ''.join(xff.split()) if xff else remote_addr
30 
31     def wait(self):
32         """
33         Optionally, return a recommended number of seconds to wait before
34         the next request.
35         """
36         return None
    BaseThrottle
    1 zz
    也可以重写allow_request方法
    1   def throttled(self, request, wait):
2         """
3         If request is throttled, determine what kind of exception to raise.
4         """
5         raise exceptions.Throttled(wait)
    可自定制返回的错误信息throttled
     1 class Throttled(APIException):
 2     status_code = status.HTTP_429_TOO_MANY_REQUESTS
 3     default_detail = _('Request was throttled.')
 4     extra_detail_singular = 'Expected available in {wait} second.'
 5     extra_detail_plural = 'Expected available in {wait} seconds.'
 6     default_code = 'throttled'
 7 
 8     def __init__(self, wait=None, detail=None, code=None):
 9         if detail is None:
10             detail = force_text(self.default_detail)
11         if wait is not None:
12             wait = math.ceil(wait)
13             detail = ' '.join((
14                 detail,
15                 force_text(ungettext(self.extra_detail_singular.format(wait=wait),
16                                      self.extra_detail_plural.format(wait=wait),
17                                      wait))))
18         self.wait = wait
19         super(Throttled, self).__init__(detail, code)
    raise exceptions.Throttled(wait)错误信息详情

     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

    1 from django.conf.urls import url
2 from app04 import views
3 urlpatterns = [
4     url('limit/',views.LimitView.as_view()),
5 
6 ]
    urls.py
     1 from django.shortcuts import render
 2 from rest_framework.views import APIView
 3 from rest_framework.response import Response
 4 from rest_framework import exceptions
 5 # from rest_framewor import
 6 # Create your views here.
 7 class MyThrottle(object):
 8     def allow_request(self,request,view):
 9         #返回False，限制
10         #返回True，不限制
11         pass
12     def wait(self):
13         return 1000
14 
15 
16 class LimitView(APIView):
17     authentication_classes = []  #不让认证用户
18     permission_classes = []  #不让验证权限
19     throttle_classes = [MyThrottle, ]
20     def get(self,request):
21         # self.dispatch
22         return Response('控制访问频率示例')
23 
24     def throttled(self, request, wait):
25         '''可定制方法设置中文错误'''
26         # raise exceptions.Throttled(wait)
27         class MyThrottle(exceptions.Throttled):
28             default_detail = '请求被限制'
29             extra_detail_singular = 'Expected available in {wait} second.'
30             extra_detail_plural = 'Expected available in {wait} seconds.'
31             default_code = '还需要再等{wait}秒'
32         raise MyThrottle(wait)
    views.py

    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：

     1 from django.shortcuts import render
 2 from rest_framework.views import APIView
 3 from rest_framework.response import Response
 4 from rest_framework import exceptions
 5 from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
 6 import time
 7 # Create your views here.
 8 RECORD = {}
 9 class MyThrottle(BaseThrottle):
10 
11     def allow_request(self,request,view):
12         '''对匿名用户进行限制，每个用户一分钟访问10次 '''
13         ctime = time.time()
14         ip = '1.1.1.1'
15         if ip not in RECORD:
16             RECORD[ip] = [ctime]
17         else:
18             #[152042123,15204212,3152042,123152042123]
19             time_list = RECORD[ip]  #获取ip里面的值
20             while True:
21                 val = time_list[-1]#取出最后一个时间，也就是访问最早的时间
22                 if (ctime-60)>val:  #吧时间大于60秒的给剔除了
23                     time_list.pop()
24                 #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
25                 else:
26                     break
27             if len(time_list) >10:
28                 return False        # 返回False，限制
29             time_list.insert(0, ctime)
30         return True   #返回True，不限制
31 
32     def wait(self):
33         ctime = time.time()
34         first_in_time = RECORD['1.1.1.1'][-1]
35         wt = 60-(ctime-first_in_time)
36         return wt
37 
38 
39 class LimitView(APIView):
40     authentication_classes = []  #不让认证用户
41     permission_classes = []  #不让验证权限
42     throttle_classes = [MyThrottle, ]
43     def get(self,request):
44         # self.dispatch
45         return Response('控制访问频率示例')
46 
47     def throttled(self, request, wait):
48         '''可定制方法设置中文错误'''
49         # raise exceptions.Throttled(wait)
50         class MyThrottle(exceptions.Throttled):
51             default_detail = '请求被限制'
52             extra_detail_singular = 'Expected available in {wait} second.'
53             extra_detail_plural = 'Expected available in {wait} seconds.'
54             default_code = '还需要再等{wait}秒'
55         raise MyThrottle(wait)
    views初级版本
      1 # from django.shortcuts import render
  2 # from rest_framework.views import APIView
  3 # from rest_framework.response import Response
  4 # from rest_framework import exceptions
  5 # from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
  6 # import time
  7 # # Create your views here.
  8 # RECORD = {}
  9 # class MyThrottle(BaseThrottle):
 10 #
 11 #     def allow_request(self,request,view):
 12 #         '''对匿名用户进行限制，每个用户一分钟访问10次 '''
 13 #         ctime = time.time()
 14 #         ip = '1.1.1.1'
 15 #         if ip not in RECORD:
 16 #             RECORD[ip] = [ctime]
 17 #         else:
 18 #             #[152042123,15204212,3152042,123152042123]
 19 #             time_list = RECORD[ip]  #获取ip里面的值
 20 #             while True:
 21 #                 val = time_list[-1]#取出最后一个时间，也就是访问最早的时间
 22 #                 if (ctime-60)>val:  #吧时间大于60秒的给剔除了
 23 #                     time_list.pop()
 24 #                 #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
 25 #                 else:
 26 #                     break
 27 #             if len(time_list) >10:
 28 #                 return False        # 返回False，限制
 29 #             time_list.insert(0, ctime)
 30 #         return True   #返回True，不限制
 31 #
 32 #     def wait(self):
 33 #         ctime = time.time()
 34 #         first_in_time = RECORD['1.1.1.1'][-1]
 35 #         wt = 60-(ctime-first_in_time)
 36 #         return wt
 37 #
 38 #
 39 # class LimitView(APIView):
 40 #     authentication_classes = []  #不让认证用户
 41 #     permission_classes = []  #不让验证权限
 42 #     throttle_classes = [MyThrottle, ]
 43 #     def get(self,request):
 44 #         # self.dispatch
 45 #         return Response('控制访问频率示例')
 46 #
 47 #     def throttled(self, request, wait):
 48 #         '''可定制方法设置中文错误'''
 49 #         # raise exceptions.Throttled(wait)
 50 #         class MyThrottle(exceptions.Throttled):
 51 #             default_detail = '请求被限制'
 52 #             extra_detail_singular = 'Expected available in {wait} second.'
 53 #             extra_detail_plural = 'Expected available in {wait} seconds.'
 54 #             default_code = '还需要再等{wait}秒'
 55 #         raise MyThrottle(wait)
 56 
 57 
 58 
 59 from django.shortcuts import render
 60 from rest_framework.views import APIView
 61 from rest_framework.response import Response
 62 from rest_framework import exceptions
 63 from rest_framework.throttling import BaseThrottle,SimpleRateThrottle  #限制访问频率
 64 import time
 65 # Create your views here.
 66 RECORD = {}
 67 class MyThrottle(BaseThrottle):
 68 
 69     def allow_request(self,request,view):
 70         '''对匿名用户进行限制，每个用户一分钟访问10次 '''
 71         ctime = time.time()
 72         self.ip =self.get_ident(request)
 73         if self.ip not in RECORD:
 74             RECORD[self.ip] = [ctime]
 75         else:
 76             #[152042123,15204212,3152042,123152042123]
 77             time_list = RECORD[self.ip]  #获取ip里面的值
 78             while True:
 79                 val = time_list[-1]#取出最后一个时间，也就是访问最早的时间
 80                 if (ctime-60)>val:  #吧时间大于60秒的给剔除了
 81                     time_list.pop()
 82                 #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
 83                 else:
 84                     break
 85             if len(time_list) >10:
 86                 return False        # 返回False，限制
 87             time_list.insert(0, ctime)
 88         return True   #返回True，不限制
 89 
 90     def wait(self):
 91         ctime = time.time()
 92         first_in_time = RECORD[self.ip][-1]
 93         wt = 60-(ctime-first_in_time)
 94         return wt
 95 
 96 
 97 class LimitView(APIView):
 98     authentication_classes = []  #不让认证用户
 99     permission_classes = []  #不让验证权限
100     throttle_classes = [MyThrottle, ]
101     def get(self,request):
102         # self.dispatch
103         return Response('控制访问频率示例')
104 
105     def throttled(self, request, wait):
106         '''可定制方法设置中文错误'''
107         # raise exceptions.Throttled(wait)
108         class MyThrottle(exceptions.Throttled):
109             default_detail = '请求被限制'
110             extra_detail_singular = 'Expected available in {wait} second.'
111             extra_detail_plural = 'Expected available in {wait} seconds.'
112             default_code = '还需要再等{wait}秒'
113         raise MyThrottle(wait)
    稍微做了改动

    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
     1 class BaseThrottle(object):
 2     """
 3     Rate throttling of requests.
 4     """
 5 
 6     def allow_request(self, request, view):
 7         """
 8         Return `True` if the request should be allowed, `False` otherwise.
 9         """
10         raise NotImplementedError('.allow_request() must be overridden')
11 
12     def get_ident(self, request):  #唯一标识
13         """
14         Identify the machine making the request by parsing HTTP_X_FORWARDED_FOR
15         if present and number of proxies is > 0. If not use all of
16         HTTP_X_FORWARDED_FOR if it is available, if not use REMOTE_ADDR.
17         """
18         xff = request.META.get('HTTP_X_FORWARDED_FOR')
19         remote_addr = request.META.get('REMOTE_ADDR') #获取IP等
20         num_proxies = api_settings.NUM_PROXIES
21 
22         if num_proxies is not None:
23             if num_proxies == 0 or xff is None:
24                 return remote_addr
25             addrs = xff.split(',')
26             client_addr = addrs[-min(num_proxies, len(addrs))]
27             return client_addr.strip()
28 
29         return ''.join(xff.split()) if xff else remote_addr
30 
31     def wait(self):
32         """
33         Optionally, return a recommended number of seconds to wait before
34         the next request.
35         """
36         return None
    BaseThrottle相当于一个抽象类
      1 class SimpleRateThrottle(BaseThrottle):
  2     """
  3     一个简单的缓存实现，只需要` get_cache_key() `。被覆盖。
  4     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。
  5     周期应该是：（的），“秒”，“M”，“min”，“h”，“小时”，“D”，“一天”。
  6     以前用于节流的请求信息存储在高速缓存中。
  7     A simple cache implementation, that only requires `.get_cache_key()`
  8     to be overridden.
  9 
 10     The rate (requests / seconds) is set by a `rate` attribute on the View
 11     class.  The attribute is a string of the form 'number_of_requests/period'.
 12 
 13     Period should be one of: ('s', 'sec', 'm', 'min', 'h', 'hour', 'd', 'day')
 14 
 15     Previous request information used for throttling is stored in the cache.
 16     """
 17     cache = default_cache
 18     timer = time.time
 19     cache_format = 'throttle_%(scope)s_%(ident)s'
 20     scope = None
 21     THROTTLE_RATES = api_settings.DEFAULT_THROTTLE_RATES
 22 
 23     def __init__(self):
 24         if not getattr(self, 'rate', None):
 25             self.rate = self.get_rate()
 26         self.num_requests, self.duration = self.parse_rate(self.rate)
 27 
 28     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
 29         """
 30         Should return a unique cache-key which can be used for throttling.
 31         Must be overridden.
 32 
 33         May return `None` if the request should not be throttled.
 34         """
 35         raise NotImplementedError('.get_cache_key() must be overridden')
 36 
 37     def get_rate(self):
 38         """
 39         Determine the string representation of the allowed request rate.
 40         """
 41         if not getattr(self, 'scope', None):
 42             msg = ("You must set either `.scope` or `.rate` for '%s' throttle" %
 43                    self.__class__.__name__)
 44             raise ImproperlyConfigured(msg)
 45 
 46         try:
 47             return self.THROTTLE_RATES[self.scope]
 48         except KeyError:
 49             msg = "No default throttle rate set for '%s' scope" % self.scope
 50             raise ImproperlyConfigured(msg)
 51 
 52     def parse_rate(self, rate):
 53         """
 54         Given the request rate string, return a two tuple of:
 55         <allowed number of requests>, <period of time in seconds>
 56         """
 57         if rate is None:
 58             return (None, None)
 59         num, period = rate.split('/')
 60         num_requests = int(num)
 61         duration = {'s': 1, 'm': 60, 'h': 3600, 'd': 86400}[period[0]]
 62         return (num_requests, duration)
 63 
 64     #1、一进来会先执行他，
 65     def allow_request(self, request, view):
 66         """
 67         Implement the check to see if the request should be throttled.
 68 
 69         On success calls `throttle_success`.
 70         On failure calls `throttle_failure`.
 71         """
 72         if self.rate is None:
 73             return True
 74 
 75         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
 76         if self.key is None:
 77             return True
 78 
 79         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，
 80                                                         # 这时候self.history就是每一个ip对应的访问记录
 81         self.now = self.timer()
 82 
 83         # Drop any requests from the history which have now passed the
 84         # throttle duration
 85         while self.history and self.history[-1] <= self.now - self.duration:
 86             self.history.pop()
 87         if len(self.history) >= self.num_requests:
 88             return self.throttle_failure()
 89         return self.throttle_success()
 90 
 91     def throttle_success(self):
 92         """
 93         Inserts the current request's timestamp along with the key
 94         into the cache.
 95         """
 96         self.history.insert(0, self.now)
 97         self.cache.set(self.key, self.history, self.duration)
 98         return True
 99 
100     def throttle_failure(self):
101         """
102         Called when a request to the API has failed due to throttling.
103         """
104         return False
105 
106     def wait(self):
107         """
108         Returns the recommended next request time in seconds.
109         """
110         if self.history:
111             remaining_duration = self.duration - (self.now - self.history[-1])
112         else:
113             remaining_duration = self.duration
114 
115         available_requests = self.num_requests - len(self.history) + 1
116         if available_requests <= 0:
117             return None
118 
119         return remaining_duration / float(available_requests)
    SimpleRateThrottle

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

    1  def __init__(self):
2         if not getattr(self, 'rate', None):
3             self.rate = self.get_rate()  #点进去看到需要些一个scope  ，2/m
4         self.num_requests, self.duration = self.parse_rate(self.rate)
    __init__
     1     def get_rate(self):
 2         """
 3         Determine the string representation of the allowed request rate.
 4         """
 5         if not getattr(self, 'scope', None):  #检测必须有scope，没有就报错了
 6             msg = ("You must set either `.scope` or `.rate` for '%s' throttle" %
 7                    self.__class__.__name__)
 8             raise ImproperlyConfigured(msg)
 9 
10         try:
11             return self.THROTTLE_RATES[self.scope]
12         except KeyError:
13             msg = "No default throttle rate set for '%s' scope" % self.scope
14             raise ImproperlyConfigured(msg)
    get_rate
     1   def parse_rate(self, rate):
 2         """
 3         Given the request rate string, return a two tuple of:
 4         <allowed number of requests>, <period of time in seconds>
 5         """
 6         if rate is None:
 7             return (None, None)
 8         num, period = rate.split('/')
 9         num_requests = int(num)
10         duration = {'s': 1, 'm': 60, 'h': 3600, 'd': 86400}[period[0]]
11         return (num_requests, duration)
    parse_rate
     1   #2、接下来会先执行他，
 2     def allow_request(self, request, view):
 3         """
 4         Implement the check to see if the request should be throttled.
 5 
 6         On success calls `throttle_success`.
 7         On failure calls `throttle_failure`.
 8         """
 9         if self.rate is None:
10             return True
11 
12         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
13         if self.key is None:
14             return True  #不限制
15         # [114521212,11452121211,45212121145,21212114,521212]
16         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，
17                                                         # 这时候self.history就是每一个ip对应的访问记录
18         self.now = self.timer()
19 
20         # Drop any requests from the history which have now passed the
21         # throttle duration
22         while self.history and self.history[-1] <= self.now - self.duration:
23             self.history.pop()
24         if len(self.history) >= self.num_requests:
25             return self.throttle_failure()
26         return self.throttle_success()
    allow_request
     1     def wait(self):
 2         """
 3         Returns the recommended next request time in seconds.
 4         """
 5         if self.history:
 6             remaining_duration = self.duration - (self.now - self.history[-1])
 7         else:
 8             remaining_duration = self.duration
 9 
10         available_requests = self.num_requests - len(self.history) + 1
11         if available_requests <= 0:
12             return None
13 
14         return remaining_duration / float(available_requests)
    wait

    代码实现：

     1 ###########用resetframework内部的限制访问频率##############
 2 class MySimpleRateThrottle(SimpleRateThrottle):
 3     scope = 'xxx'
 4     def get_cache_key(self, request, view):
 5         return self.get_ident(request)  #返回唯一标识IP
 6 
 7 class LimitView(APIView):
 8     authentication_classes = []  #不让认证用户
 9     permission_classes = []  #不让验证权限
10     throttle_classes = [MySimpleRateThrottle, ]
11     def get(self,request):
12         # self.dispatch
13         return Response('控制访问频率示例')
14 
15     def throttled(self, request, wait):
16         '''可定制方法设置中文错误'''
17         # raise exceptions.Throttled(wait)
18         class MyThrottle(exceptions.Throttled):
19             default_detail = '请求被限制'
20             extra_detail_singular = 'Expected available in {wait} second.'
21             extra_detail_plural = 'Expected available in {wait} seconds.'
22             default_code = '还需要再等{wait}秒'
23         raise MyThrottle(wait)
    views.py

    记得在settings里面配置

     1 REST_FRAMEWORK = {
 2     'UNAUTHENTICATED_USER': None,
 3     'UNAUTHENTICATED_TOKEN': None,  #将匿名用户设置为None
 4     "DEFAULT_AUTHENTICATION_CLASSES": [
 5         "app01.utils.MyAuthentication",
 6     ],
 7     'DEFAULT_PERMISSION_CLASSES':[
 8         # "app03.utils.MyPermission",#设置路径，
 9     ],
10     'DEFAULT_THROTTLE_RATES':{
11         'xxx':'2/minute'  #2分钟
12     }
13 }
14 
15 #缓存：放在文件
16 CACHES = {
17     'default': {
18         'BACKEND': 'django.core.cache.backends.filebased.FileBasedCache',
19         'LOCATION': 'cache',   #文件路径
20     }
21 }
    settings.py

    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
    1 from django.contrib import admin
2 
3 from django.conf.urls import url, include
4 from app05 import views
5 
6 urlpatterns = [
7     url('index/',views.IndexView.as_view()),
8     url('manage/',views.ManageView.as_view()),
9 ]
    urls.py
     1 from django.shortcuts import render
 2 from rest_framework.views import APIView
 3 from rest_framework.response import Response
 4 from rest_framework.authentication import BaseAuthentication  #认证需要
 5 from rest_framework.throttling import BaseThrottle,SimpleRateThrottle #限流处理
 6 from rest_framework.permissions import BasePermission
 7 from rest_framework import exceptions
 8 from app01 import models
 9 # Create your views here.
10 ###############3##认证#####################
11 class MyAuthentcate(BaseAuthentication):
12     '''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'''
13     def authenticate(self, request):
14         token = request.query_params.get('token')
15         obj = models.UserInfo.objects.filter(token=token).first()
16         if obj:
17             return (obj.username,obj.token)
18         return None  #表示我不处理
19 
20 ##################权限#####################
21 class MyPermission(BasePermission):
22     message='无权访问'
23     def has_permission(self, request, view):
24         if request.user:
25             return True  #true表示有权限
26         return False  #false表示无权限
27 
28 class AdminPermission(BasePermission):
29     message = '无权访问'
30 
31     def has_permission(self, request, view):
32         if request.user=='haiyan':
33             return True  # true表示有权限
34         return False  # false表示无权限
35 
36 ############3#####限流##################3##
37 class AnonThrottle(SimpleRateThrottle):
38     scope = 'wdp_anon'  #相当于设置了最大的访问次数和时间
39     def get_cache_key(self, request, view):
40         if request.user:
41             return None  #返回None表示我不限制，登录用户我不管
42         #匿名用户
43         return self.get_ident(request)  #返回一个唯一标识IP
44 
45 class UserThrottle(SimpleRateThrottle):
46     scope = 'wdp_user'
47     def get_cache_key(self, request, view):
48         #登录用户
49         if request.user:
50             return request.user
51         return None  #返回NOne表示匿名用户我不管
52 
53 
54 ##################视图#####################
55 #首页支持匿名访问,
56 #无需要登录就可以访问
57 class IndexView(APIView):
58     authentication_classes = [MyAuthentcate,]   #认证判断他是不是匿名用户
59     permission_classes = []   #一般主页就不需要权限验证了
60     throttle_classes = [AnonThrottle,UserThrottle,]  #对匿名用户和普通用户的访问限制
61 
62     def get(self,request):
63         # self.dispatch
64         return Response('访问首页')
65 
66     def throttled(self, request, wait):
67         '''可定制方法设置中文错误'''
68 
69         # raise exceptions.Throttled(wait)
70         class MyThrottle(exceptions.Throttled):
71             default_detail = '请求被限制'
72             extra_detail_singular = 'Expected available in {wait} second.'
73             extra_detail_plural = 'Expected available in {wait} seconds.'
74             default_code = '还需要再等{wait}秒'
75 
76         raise MyThrottle(wait)
77 
78 #需登录就可以访问
79 class ManageView(APIView):
80     authentication_classes = [MyAuthentcate, ]  # 认证判断他是不是匿名用户
81     permission_classes = [MyPermission,]  # 一般主页就不需要权限验证了
82     throttle_classes = [AnonThrottle, UserThrottle, ]  # 对匿名用户和普通用户的访问限制
83 
84     def get(self, request):
85         # self.dispatch
86         return Response('管理人员访问页面')
87 
88     def throttled(self, request, wait):
89         '''可定制方法设置中文错误'''
90 
91         # raise exceptions.Throttled(wait)
92         class MyThrottle(exceptions.Throttled):
93             default_detail = '请求被限制'
94             extra_detail_singular = 'Expected available in {wait} second.'
95             extra_detail_plural = 'Expected available in {wait} seconds.'
96             default_code = '还需要再等{wait}秒'
97 
98         raise MyThrottle(wait)
    views.py

    四、总结

    回到顶部

    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:
    第一个C#程序
    定位网页元素
    盒子模型
    浮动
    css3美化网页元素
    html css3
    java表单基础
    表单
    html5基础
    java程序题目解析
  • 原文地址：https://www.cnblogs.com/zhangningyang/p/8471531.html
Copyright © 2011-2022 走看看