Django REST framework 限流功能的使用

// 前端函数限流示例
function throttle(fn, delay) {
    var timer;
    return function () {
        var _this = this;
        var args = arguments;
        if (timer) {
            return;
        }
        timer = setTimeout(function () {
            fn.apply(_this, args);
            timer = null;
        }, delay)
    }
}

# demo/settings.py

REST_FRAMEWORK = {
    # ...
    'DEFAULT_THROTTLE_CLASSES': (
        'rest_framework.throttling.AnonRateThrottle',
        'rest_framework.throttling.UserRateThrottle',
         'rest_framework.throttling.ScopedRateThrottle',
    ),
    'DEFAULT_THROTTLE_RATES': {
        'anon': '10/day',
        'user': '2/day'
    },
}

# article/views.py

# 基于ViewSet的限流
class ArticleViewSet(viewsets.ModelViewSet, ExceptionMixin):
    """
    允许用户查看或编辑的API路径。
    """
    queryset = Article.objects.all()
    # 使用默认的用户限流
    throttle_classes = (UserRateThrottle,)
    serializer_class = ArticleSerializer

# 基于view的限流
@throttle_classes([UserRateThrottle])

$ curl -H 'Accept: application/json; indent=4' -u root:root   http://127.0.0.1:8000/api/article/1/ 
{
    "id": 1,
    "creator": "admin",
    "tag": "现代诗",
    "title": "如果",
    "content": "今生今世 永不再将你想起\n除了\n除了在有些个\n因落泪而湿润的夜里 如果\n如果你愿意"
}

from functools import wraps

TOTAL_RATE = 2

FUNC_SCOPE = ['test', 'test1']


def rate_count(func):
    func_num = {
        # 需要注意函数名不能重复
        func.__name__: 0
    }

    @wraps(func)
    def wrapper():
        if func.__name__ in FUNC_SCOPE:
            if func_num[func.__name__] >= TOTAL_RATE:
                raise Exception(f"{func.__name__}函数调用超过设定次数")
            result = func()
            func_num[func.__name__] += 1
            print(f" 函数 {func.__name__} 调用次数为： {func_num[func.__name__]}")
            return result
        else:
            # 不在计数限制的函数不受限制
            return func()

    return wrapper


@rate_count
def test1():
    pass


@rate_count
def test2():
    print("test2")
    pass


if __name__ == "__main__":
    try:
        test2()
        test2()
        test1()
        test1()
        test1()
    except Exception as e:
        print(e)
    test2()
    test2()
    
"""
test2
test2
 函数 test1 调用次数为： 1
 函数 test1 调用次数为： 2
test1函数调用超过设定次数
test2
test2
"""

class SimpleRateThrottle(BaseThrottle):
   
    # ......
    
    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)
        if self.key is None:
            return True

        self.history = self.cache.get(self.key, [])
        self.now = self.timer()

        # 根据设置时间的限制改变请求次数的缓存
        while self.history and self.history[-1] <= self.now - self.duration:
            self.history.pop()
        # 核心逻辑就是这里判断请求次数
        if len(self.history) >= self.num_requests:
            return self.throttle_failure()
        return self.throttle_success()
    
    # ......
    
class UserRateThrottle(SimpleRateThrottle):
    """
    Limits the rate of API calls that may be made by a given user.

    The user id will be used as a unique cache key if the user is
    authenticated.  For anonymous requests, the IP address of the request will
    be used.
    """
    scope = 'user'

    def get_cache_key(self, request, view):
        if request.user.is_authenticated:
            ident = request.user.pk
        else:
            # 考虑到用户没有认证的情况 与 AnonRateThrottle 中 key 一致
            ident = self.get_ident(request)
        # 根据设置的范围构建缓存的 key
        return self.cache_format % {
            'scope': self.scope,
            'ident': ident
        }