php+redis消息队列实现抢购功能

<?php/*********************************************** 抢购模块** @author liubin* @date 2016-02-10** ab -n 1000 -c 100 http://192.168.16.73/Seckill/buy.php**/class seckill extends common{ private $_orderModel = null; private $_goodsModel = null; private $_redis = null; /*  * 错误信息 */ protected $_error = ''; /**  * 构造器  * */ public function __construct() {  if($this->_orderModel === null){   $this->_orderModel = new OrderModel();  }  if($this->_goodsModel === null){   $this->_goodsModel = new GoodsModel();  }  if($this->_redis === null){   $this->_redis = new QRedis();   } } /*  * 秒杀API  *   * @author liubin  * @date 2017-02-10 */ public function addQsec(){  $gid = intval($_GET['gid']);  $type = isset($_GET['type']) ? $_GET['type'] : 'mysql';  switch ($type) {   case 'mysql':    $this->order_check_mysql($gid);    echo $this->getError();    break;   case 'redis':    $this->order_check_redis($gid);    echo $this->getError();    break;   case 'transaction':    $this->order_check_transaction($gid);    echo $this->getError();    break;   default:    echo '类型错误';    break;  } } /*  * 获取错误信息  *   * @author liubin  * @date 2017-02-10 */ public function getError(){  return $this->_error; } /*  * 基于mysql验证库存信息  * @desc 高并发下会导致超卖  *  * @author liubin  * @date 2017-02-10 */ protected function order_check_mysql($gid){  $model = $this->_goodsModel;  $pdo = $model->getHandler();  $gid = intval($gid);  /*   * 1：$sql_forlock如果不加事务，不加写锁：   * 超卖非常严重，就不说了   *    * 2：$sql_forlock如果不加事务，只加写锁：   * 第一个会话读$sql_forlock时加写锁，第一个会话$sql_forlock查询结束会释放该行锁.   * 第二个会话在第一个会话释放后读$sql_forlock的写锁时，会再次$sql_forlock查库存   * 导致超卖现象产生   *  */  $sql_forlock = 'select * from goods where id = '.$gid .' limit 1 for update';  //$sql_forlock = 'select * from goods where id = '.$gid .' limit 1';  $result = $pdo->query($sql_forlock,PDO::FETCH_ASSOC);  $goodsInfo = $result->fetch();  if($goodsInfo['counts']>0){   //去库存   $gid = $goodsInfo['id'];   $sql_inventory = 'UPDATE goods SET counts = counts - 1 WHERE id = '.$gid;   $result = $this->_goodsModel->exect($sql_inventory);   if($result){    //创订单    $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);    if($order_rs){     $this->_error = '购买成功';     return true;    }   }  }  $this->_error = '库存不足';  return false; } /*  * 基于redis队列验证库存信息  * @desc Redis是底层是单线程的,命令执行是原子操作,包括lpush,lpop等.高并发下不会导致超卖  *  * @author liubin  * @date 2017-02-10 */ protected function order_check_redis($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);  $this->_error = '购买成功';  return true; } /*  * 基于mysql事务验证库存信息  * @desc 事务 和 行锁 模式,高并发下不会导致超卖，但效率会慢点  * @author liubin  * @date 2017-02-10  说明：  如果$sql_forlock不加写锁，并发时，$sql_forlock查询的记录存都大于0，可以减库存操作.  如果$sql_forlock加了写锁，并发时，$sql_forlock查询是等待第一次链接释放后查询.所以库存最多就是5 */ protected function order_check_transaction($gid){  $model = $this->_goodsModel;  $pdo = $model->getHandler();  $gid = intval($gid);  try{   $pdo->beginTransaction();//开启事务处理   /*    * 1：$sql_forlock如果只加事务，不加写锁：    * 开启事务    * 因为没有加锁，读$sql_forlock后，并发时$sql_inventory之前还可以再读。    * $sql_inventory之后和commit之前才会锁定    * 出现超卖跟事务的一致性不冲突    *     *    * 2：$sql_forlock如果加了事务，又加读锁：    * 开启事务    * 第一个会话读$sql_forlock时加读锁，并发时，第二个会话也允许获得$sql_forlock的读锁，    * 但是在第一个会话执行去库存操作时（写锁），写锁便会等待第二个会话的读锁，第二个会话执行写操作时，写锁便会等待第一个会话的读锁，    * 出现死锁    * 3：$sql_forlock如果加了事务，又加写锁：    * 开启事务    * 第一个会话读$sql_forlock时加写锁，直到commit才会释放写锁，并发查询不会出现超卖现象。    *   */   $sql_forlock = 'select * from goods where id = '.$gid .' limit 1 for update';   //$sql_forlock = 'select * from goods where id = '.$gid .' limit 1 LOCK IN SHARE MODE';   //$sql_forlock = 'select * from goods where id = '.$gid .' limit 1';   $result = $pdo->query($sql_forlock,PDO::FETCH_ASSOC);   $goodsInfo = $result->fetch();   if($goodsInfo['counts']>0){    //去库存    $gid = $goodsInfo['id'];    $sql_inventory = 'UPDATE goods SET counts = counts - 1 WHERE id = '.$gid;    $result = $this->_goodsModel->exect($sql_inventory);    if(!$result){     $pdo->rollBack();     $this->_error = '库存减少失败';     return false;    }    //创订单    $data    = [];    $data['id']   = 'null';    $data['order_id'] = $this->_orderModel->buildOrderNo();    $data['goods_id'] = $goodsInfo['id'];    $data['uid']  = 'abc';    $data['addtime'] = time();    $sql = 'insert into orders (id,order_id,goods_id,uid,addtime) values ('.$data['id'].',"'.$data['order_id'].'","'.$data['goods_id'].'","'.$data['uid'].'","'.$data['addtime'].'")';       $result = $pdo->exec($sql);    if(!$result){     $pdo->rollBack();     $this->_error = '订单创建失败';     return false;    }    $pdo->commit();//提交    $this->_error = '购买成功';    return true;   }else{    $this->_error = '库存不足';    return false;   }  }catch(PDOException $e){   echo $e->getMessage();   $pdo->rollBack();  } } /*  * 创建订单  * mysql 事物处理，也可以用存储过程  * */ private function create_order($goodsInfo){  //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);  return true; }}