命令：
subscribe __keyevent@0__:expired

命令：
setex test_key_name 30 ceshi

<?php
//設(shè)置php腳本執(zhí)行時(shí)間
set_time_limit(0);
//設(shè)置socket連接超時(shí)時(shí)間
ini_set('default_socket_timeout', -1);
class redisSubscribe 
{
    protected $config = [
        "host" => "127.0.0.1",
        "password" => "6379"
    ];
    protected $redis;
    public function __construct() 
    {
        try {
            $this->redis = new \Redis();
            $this->redis->pconnect($this->config['host'],$this->config['password']);
        } catch(\Exception $e) {
            echo "redis錯(cuò)誤：".$e->getMessage().PHP_EOL;
        }
    }
    // 普通消息訂閱
    public function normal()
    {
        //聲明頻道名稱
        $channelName = "test";
        try {
            $this->redis->subscribe([$channelName], function ($redis, $channel, $msg)
            {
                echo 'channel:' . $channel . ',message:' . $msg . PHP_EOL;
                file_put_contents('subscribe.log',"\n-".$msg."-\n",FILE_APPEND);
            });
        } catch (\Exception $e) {
            echo $e->getMessage();
        }
    }
    // 訂閱Key失效事件的頻道
    public function keyNotify()
    {
        echo "wathc keyNotify start~~".PHP_EOL;
        // Key事件回調(diào)
        //$channel = "__keyevent@0__:expired";        // 0號(hào)庫(kù)的Key過期事件頻道名
        $channel = "__keyevent@*__:expired";        // 所有庫(kù)的Key過期事件頻道名
        try {
            $this->redis->subscribe([$channel], function ($redis, $channel, $msg)
            {
                echo 'channel:' . $channel . '===========' . ',message:' . $msg . PHP_EOL;
                file_put_contents('subscribe.log',"\n-".$msg."-\n",FILE_APPEND);
            });
        } catch (\Exception $e) {
            echo $e->getMessage();
        }
    }
}
(new redisSubscribe())->keyNotify();
?>

/**
     * @Notes: 高并發(fā)防止重復(fù)提交（插入數(shù)據(jù)） 【保證接口的冪等性】
     * @Interface preventRepeatSubmit
     * @return mixed
     * @author: bqs
     * @Time: 2020/6/19 14:56
     */
    public function preventRepeatSubmit()
    {
        /* 比如查詢某條(什么條件)記錄是否存在，分布式鎖機(jī)制[redis的原子性setnx]
         * 1. 通過條件拼接為唯一的鍵名，將鍵名setnx設(shè)置一個(gè)30s有效期的值
         * 2. setnx設(shè)置鍵名不成功(返回0)表示已經(jīng)存在，接口則直接返回記錄已經(jīng)存在
         * 3. 根據(jù)該條件查詢數(shù)據(jù)庫(kù)記錄，如果存在，接口再返回記錄已經(jīng)存在
         * 【只要添加記錄前需要查詢什么是否存在則都需要考慮高并發(fā)情況，則通過此方案】
        */
        $redis = Redis::db(0);
        $no = date('YmdHis',time()).mt_rand(1000,9999);
        //$no = 202006191537447811;
        // 是否添加鎖表
        $addLock = false;
        if ($redis->setnx($no,1)) {
            $redis->expire($no,30);     //設(shè)置30s過期時(shí)間
        } else {
            $addLock = true;        // 訂單已經(jīng)存在則鎖住
        }
        // 數(shù)據(jù)庫(kù)查詢是否存在
        $isExist = Db::name('ztest')->where(['no'=>$no])->find();
        if ($isExist) {
            $addLock = true;
        }
        if (!$addLock) {
            $data = [
                "no" => $no,
                "tab_num" => 2,
                "stock" => 20,
                "create_time" => time()
            ];
            $res = Db::name('ztest')->insertGetId($data);
        }
        return "添加數(shù)據(jù)成功";
    }

/**
     * @Notes: 高并發(fā)樂觀鎖 - （更新數(shù)據(jù)）
     * @Interface testConcurrence
     * @return mixed
     * @author: bqs
     * @Time: 2020/6/19 14:25
     */
    public function testConcurrence()
    {
        // 開啟事務(wù)
        Db::startTrans();
        // 查詢ID25當(dāng)前的庫(kù)存和版本號(hào)
        $curr = Db::name('ztest')->field('stock,version')->where(['id'=>25])->find();
        // 判斷庫(kù)存是否小于0
        if ($curr && $curr['stock'] <= 0) {
            throw new \Exception('物品已售罄',302);
        }
        try {
            // 修改庫(kù)存 - 獲取ID25的行瑣
            $updateRes = Db::name('ztest')->where(['id'=>25,'version'=>$curr['version']])->update(['stock'=>$curr['stock']-1,'version'=>$curr['version']+1]);
            // 標(biāo)識(shí)并發(fā)過來修改的，拿到的version太舊，事務(wù)回滾重新回到查詢?cè)僮咭槐?
            if (!$updateRes) {
                Db::rollback();
            }
        } catch(\Exception $e) {
            Db::rollback();
            // 記錄日志，或者返回
        }
        // 事務(wù)提交
        Db::commit();
        return '購(gòu)買成功了';
    }