PHP里redis秒杀案例

<?php
   /*-------------------------------------------------
    * redis驱动类，需要安装phpredis扩展
    *
    * @athor  liubin
    * @link   http://pecl.php.net/package/redis
    * @date   2016-02-09
    *-------------------------------------------------
   */
   class QRedis{
      
        private $_redis = null;
      /** 构造**/
      public function __construct(){
         if($this->_redis === null){
            try{
               $redis    = new Redis();
               $hanedel   = $redis->connect('127.0.0.1',6379);
               if($hanedel){
                  $this->_redis = $redis;
               }else{
                  echo 'redis服务器无法链接';
                  $this->_redis = false;
                  exit;
               }
            }catch(RedisException $e){
               echo 'phpRedis扩展没有安装：' . $e->getMessage();
               exit;
            }
         }
      }
   /** 队列尾追加**/
      public function addRlist($key,$value){
         $result = $this->_redis->rPush($key,$value);
         return $result;
      }
   /** 队列头追**/
      public function addLlist($key,$value){
         $result = $this->_redis->lPush($key,$value);
         return $result;
      }
   /** 头出队列**/
      public function lpoplist($key){
         $result=$this->_redis->lPop($key);
         return $result;
      }
   /** 尾出队列**/
      public function rpoplist($key){
         $result=$this->_redis->rPop($key);
         return $result;
      }
    /** 查看队列**/
      public function showlist($key){
         $result = $this->_redis->lRange($key, 0, -1);
         return $result;
      }
    /** 队列数量**/
      public function listcount($key){
         $result = $this->_redis->lSize($key);
         return $result;
      }
   /** 清空队列**/
      public function clearlist($key){
         $result = $this->_redis->delete($key);
         return $result;
      }
    /** 获取redis资源对象**/
      public function getHandel(){
         return $this->_redis;
      }
   }
?>

以上是建立redis链接，下面是实现库存减少(简单案例实现)

/*
 * 基于redis队列验证库存信息
 * @desc Redis是底层是单线程的,命令执行是原子操作,包括lpush,lpop等.高并发下不会导致超卖
*/
protected function order_check_redis($gid){

   $goodsInfo     = $this->_goodsModel->getGoods($gid);
   if(!$goodsInfo){
      $this->_error = '商品不存在';
      return false;
   }

   $key   = 'goods_list_'.$goodsInfo['id'];
   $count     = $this->_redis->getHandel()->lpop($key);
   if(!$count){
      $this->_error = '库存不足';
      return false;
   }

   //生成订单
   $data           = [];
   $data['order_id']  = $this->_orderModel->buildOrderNo();
   $data['goods_id']  = $goodsInfo['id'];
   $data['addtime']   = time();
   $data['uid']      = 1;
   $order_rs        = $this->_orderModel->create_order($data);
   
   //库存减少
   $gid   = $goodsInfo['id'];
   $sql   = 'UPDATE goods SET counts = counts - 1 WHERE id = '.$gid;
   $result = $this->_goodsModel->exect($sql);
   $this->_error = '购买成功';
   return true;
}