七、频率控制

7.1 定义频率控制类

• utils/throttle.py：定义频率控制类的allow_request和wait方法

  from rest_framework.throttling import BaseThrottle
  import time
  
  VISIT_RECORD = {}
  
  
  class MyThrottle(BaseThrottle):
  
      def __init__(self):
          self.history = None
  
      def allow_request(self, request, view):
          """
          示例：以IP限流
          访问列表 {IP: [time1, time2, time3]}
          """
          # 1 获取请求的IP地址
          ip = request.META.get("REMOTE_ADDR")
          # 2 判断IP地址是否在访问列表
          now = time.time()
          if ip not in VISIT_RECORD:
              VISIT_RECORD[ip] = [now, ]
              return True
          history = VISIT_RECORD[ip]
          history.insert(0, now)
          # 3 确保列表里最新访问时间以及最老的访问时间差 是1分钟
          while history and history[0] - history[-1] > 60:
              history.pop()
          self.history = history
          # 4 得到列表长度，判断是否是允许的次数
          if len(history) > 3:
              return False
          else:
              return True
  
      def wait(self):
          """ 需要等待时间 """
          time = 60 - (self.history[0] - self.history[-1])
          return time
  
  

7.2 应用局部频率控制

• views.py

  from rest_framework.views import APIView
  from utils.auth import MyAuth
  from utils.permission import MyPermission
  
  
  class TestView(APIView):
      authentication_classes = [MyAuth, ]  # 局部认证
      permission_classes = [MyPermission, ]  # 局部权限
      throttle_classes = [MyThrottle, ]  # 频率控制
  
      def get(self, request):
          pass
     
  

7.3 利用框架

• 提供了四种频率控制类

  from rest_framework.throttling import AnonRateThrottle
  from rest_framework.throttling import UserRateThrottle
  from rest_framework.throttling import ScopedRateThrottle
  from rest_framework.throttling import SimpleRateThrottle