function __construct()
{
$this->yaf = \ImReworks\Yaf::getInstance();
$this->db = $this->yaf->db;
$this->db->connect();
$this->dbs = new \Swoole\SelectDB($this->db);
}
/**
* 检查连接状态，如果连接断开，则重新连接
*/
function check_status()
{
if (!$this->_db->ping()) {
$this->_db->close();
$this->_db->connect();
}
}