PHP实现redis限制单ip、单用户的访问次数功能

<?php
$redis = new Redis();
$redis->connect('127.0.0.1', 6379);
$redis->auth("php001");
//这个key记录该ip的访问次数 也可改成用户id
//$key = 'userid_11100';
$key=get_real_ip();
//限制次数为5
$limit = 5;
$check = $redis->exists($key);
if($check){
  $redis->incr($key);
  $count = $redis->get($key);
  if($count > 5){
    exit('请求太频繁，请稍后再试！');
  }
}else{
  $redis->incr($key);
  //限制时间为60秒
  $redis->expire($key,60);
}
$count = $redis->get($key);
echo '第 '.$count.' 次请求';
//获取客户端真实ip地址
function get_real_ip(){
  static $realip;
  if(isset($_SERVER)){
    if(isset($_SERVER['HTTP_X_FORWARDED_FOR'])){
      $realip=$_SERVER['HTTP_X_FORWARDED_FOR'];
    }else if(isset($_SERVER['HTTP_CLIENT_IP'])){
      $realip=$_SERVER['HTTP_CLIENT_IP'];
    }else{
      $realip=$_SERVER['REMOTE_ADDR'];
    }
  }else{
    if(getenv('HTTP_X_FORWARDED_FOR')){
      $realip=getenv('HTTP_X_FORWARDED_FOR');
    }else if(getenv('HTTP_CLIENT_IP')){
      $realip=getenv('HTTP_CLIENT_IP');
    }else{
      $realip=getenv('REMOTE_ADDR');
    }
  }
  return $realip;
}
?>