时间窗口算法简易版

<?php
session_start();
$time = 60;//60秒
$count = 10; //可访问 10次

//第一次初始化
if(!isset($_SESSION[‘count‘])){

    $_SESSION[‘count‘] = 1;
    $_SESSION[‘time‘] = time();
    $_SESSION[‘cha‘] = 0;
    $_SESSION[‘status‘] = ‘success‘;
    print_r($_SESSION);

}else {


    $now = time();
    $cha = $now - $_SESSION[‘time‘];
    $avg = intval($time / $count);//平均多少秒可获得一次机会

    //如果超过次数
    if($_SESSION[‘count‘] > $count){

        //如果时差超过平均可获得次数的时长
        if($cha > $avg){

            $_SESSION[‘count‘] -= intval($cha / $avg); //计算可得多少次机会
            $_SESSION[‘count‘] = max($_SESSION[‘count‘], 0);//修正次数不能为负。

            $_SESSION[‘count‘]++;
            $_SESSION[‘time‘] = $now;
            $_SESSION[‘cha‘] = $cha;
            $_SESSION[‘status‘] = ‘success‘;
            print_r($_SESSION);

        }else{

            //如果时差没有超过 $avg ，则还是失败。
            $_SESSION[‘cha‘] = $cha;
            $_SESSION[‘status‘] = ‘fail‘;
            print_r($_SESSION);

        }


    }else{
        //如果没超过次数正常访问

        if($cha > $avg) {
            $_SESSION[‘count‘] -= intval($cha / $avg); //计算可得多少次机会
            $_SESSION[‘count‘] = max($_SESSION[‘count‘], 0);//修正次数不能为负。
        }

        $_SESSION[‘count‘]++;
        $_SESSION[‘time‘] = $now;
        $_SESSION[‘cha‘] = $cha;
        $_SESSION[‘status‘] = ‘success‘;
        print_r($_SESSION);

    }


}