DRF之限制单位时间访问次数

Posted 2020-12-26 fqh202

1、节流源码流程：

# step 1
def dispatch(self, request, *args, **kwargs):
    try:
        self.initial(request, *args, **kwargs)


# step 2
def initial(self, request, *args, **kwargs):
    self.perform_authentication(request)  # 先认证
    self.check_permissions(request)  # 随后权限管理
    self.check_throttles(request)  # 最后是节流管理
    

# step 3
def check_throttles(self, request):
    for throttle in self.get_throttles():
        # 调用类的allow_request函数，返回False,则节流有效，反之，不节流
        if not throttle.allow_request(request, self):
            self.throttled(request, throttle.wait())


# step 4 :获取节流类的实例化对象列表
def get_throttles(self):
    return [throttle() for throttle in self.throttle_classes]


# step 5

from rest_framework.throttling import BaseThrottle

# 默认的节流类
class SimpleRateThrottle(BaseThrottle):
    cache = default_cache
    timer = time.time
    cache_format = 'throttle_%(scope)s_%(ident)s'
    scope = None
    THROTTLE_RATES = api_settings.DEFAULT_THROTTLE_RATES  # 可以自定义

    def get_cache_key(self, request, view):
        pass

2、自定义节流：

# 相关参数的解析方式
def parse_rate(self, rate):
    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)


# setting.py
REST_FRAMEWORK = {
    'DEFAULT_THROTTLE_RATES':{
        'anon':'5/m'  # 表示每分钟只能访问5次数
    },
}


# views.py
class MyThrottle(SimpleRateThrottle):
    scope = 'anon'  # 标识符

    def get_cache_key(self, request, view):
        return self.cache_format % {
            'scope': self.scope,
            'ident': self.get_ident(request)
        }


class Throttle(object):
    throttle_classes = [MyThrottle,]


class UserView(Auth,Throttle,APIView):
    """所有用户都有权限，也可以限制匿名用户，去掉Auth类参数即可"""
    def get(self,request,*args,**kwargs):
        return HttpResponse('<h1>用户界面</h1>')

3、错误页面：

4、请求次数限制方法，可以对ip(对代理用户无效)、用户名或者手机等特定标识节流：

dict={
    ip:[11:12,11:10,11:01,]  # 最新访问时间从左侧插入
    # 例如若限制为：5/m，那么每次插入元素前都会与相应的元素比较时间差，若在时间差内则插入，否则不插入
}