How to install third party extension for Yii2?

Question

Yii

Hello! I want to install wiki.workerman.net/Workerman_documentation#Installation
I add it to composer, I create a file at the root with the following content:

namespace app;
use Workerman\Worker;
use Workerman\Lib\Timer;
use app\models\Auction;
require_once './vendor/workerman/workerman/Autoloader.php';

$task = new Worker();
$task->onWorkerStart = function($task){
    $time_interval = 5;
    $timer_id = Timer::add($time_interval,
        function(){
            $endedAuctionExist = Auction::find()->where(['ended_at'=>2])->exists();
            if($endedAuctionExist){
                $auctions = Auction::find()->where(['ended_at'=>2])->all();
                foreach($auctions as $auction){
                    /* @var $auction Auction */
                    $auction->winner_id = 10;
                    $auction->save();
                }
            }

        }
    );
};
Worker::runAll();

Workerman starts:

Workerman[auction.php] start in DEBUG mode
----------------------- WORKERMAN -----------------------------
Workerman version:3.3.4          PHP version:5.4.16
------------------------ WORKERS -------------------------------
user          worker        listen        processes status
root          none          none           1         [OK] 
----------------------------------------------------------------
Press Ctrl-C to quit. Start success.
PHP Fatal error:  Class 'app\models\Auction' not found in auction.php on line 15

Tell me what's wrong?

Answer 1

php already told you:
PHP Fatal error: Class 'app\models\Auction' not found in auction.php on
line
15 app\models\auction.php ? does it really have namespace app\models ? And wasn't the path to app (application directory) overridden? Nothing else should fail.