logSystem-advance/backend/controllers/BaseController.php

<?php
namespace backend\controllers;

use yii\web\Controller;

/**
 * Class BaseController
 * @package backend\controllers
 */
class BaseController extends Controller
{
	public function init()
	{
		\Yii::$app->response->format = \yii\web\Response::FORMAT_JSON;
		parent::init();
	}

	public function beforeAction($action)
	{
		//todo
		/*if (Yii::$app->user->isGuest) {

		}*/
		return true;
	}
}