基于Swoole扩展开发异步高性能的MySQL代理服务器_MySQL

class DBServer{    protected $pool_size = 20;    protected $idle_pool = array(); //空闲连接    protected $busy_pool = array(); //工作连接    protected $wait_queue = array(); //等待的请求    protected $wait_queue_max = 100; //等待队列的最大长度，超过后将拒绝新的请求    /**     * @var swoole_server     */    protected $serv;    function run()    {        $serv = new swoole_server("127.0.0.1", 9509);        $serv->set(array(            'worker_num' => 1,        ));        $serv->on('WorkerStart', array($this, 'onStart'));        //$serv->on('Connect', array($this, 'onConnect'));        $serv->on('Receive', array($this, 'onReceive'));        //$serv->on('Close', array($this, 'onClose'));        $serv->start();    }    function onStart($serv)    {        $this->serv = $serv;        for ($i = 0; $i < $this->pool_size; $i++) {            $db = new mysqli;            $db->connect('127.0.0.1', 'root', 'root', 'test');            $db_sock = swoole_get_mysqli_sock($db);            swoole_event_add($db_sock, array($this, 'onSQLReady'));            $this->idle_pool[] = array(                'mysqli' => $db,                'db_sock' => $db_sock,                'fd' => 0,            );        }        echo "Server: start.Swoole version is [" . SWOOLE_VERSION . "]/n";    }    function onSQLReady($db_sock)    {        $db_res = $this->busy_pool[$db_sock];        $mysqli = $db_res['mysqli'];        $fd = $db_res['fd'];        echo __METHOD__ . ": client_sock=$fd|db_sock=$db_sock/n";        if ($result = $mysqli->reap_async_query()) {            $ret = var_export($result->fetch_all(MYSQLI_ASSOC), true) . "/n";            $this->serv->send($fd, $ret);            if (is_object($result)) {                mysqli_free_result($result);            }        } else {            $this->serv->send($fd, sprintf("MySQLi Error: %s/n", mysqli_error($mysqli)));        }        //release mysqli object        $this->idle_pool[] = $db_res;        unset($this->busy_pool[$db_sock]);        //这里可以取出一个等待请求        if (count($this->wait_queue) > 0) {            $idle_n = count($this->idle_pool);            for ($i = 0; $i < $idle_n; $i++) {                $req = array_shift($this->wait_queue);                $this->doQuery($req['fd'], $req['sql']);            }        }    }    function onReceive($serv, $fd, $from_id, $data)    {        //没有空闲的数据库连接        if (count($this->idle_pool) == 0) {            //等待队列未满            if (count($this->wait_queue) < $this->wait_queue_max) {                $this->wait_queue[] = array(                    'fd' => $fd,                    'sql' => $data,                );            } else {                $this->serv->send($fd, "request too many, Please try again later.");            }        } else {            $this->doQuery($fd, $data);        }    }    function doQuery($fd, $sql)    {        //从空闲池中移除        $db = array_pop($this->idle_pool);        /**         * @var mysqli         */        $mysqli = $db['mysqli'];        for ($i = 0; $i < 2; $i++) {            $result = $mysqli->query($sql, MYSQLI_ASYNC);            if ($result === false) {                if ($mysqli->errno == 2013 or $mysqli->errno == 2006) {                    $mysqli->close();                    $r = $mysqli->connect();                    if ($r === true) continue;                }            }            break;        }        $db['fd'] = $fd;        //加入工作池中        $this->busy_pool[$db['db_sock']] = $db;    }}$server = new DBServer();$server->run();