$sub = new \Mix\Redis\Subscriber\Subscriber('127.0.0.1', 6379, '', 5); // 连接失败将抛出异常
$sub->subscribe('foo', 'bar'); // 订阅失败将抛出异常
$chan = $sub->channel();
while (true) {
    $data = $chan->pop();
    if (empty($data)) { // 手动close与redis异常断开都会导致返回false
        if (!$sub->closed) {
            // redis异常断开处理
            var_dump('Redis connection is disconnected abnormally');
        }
        break;
    }
    var_dump($data);
}