FRONTEND_MVC/controllers/NewsController.php

<?php

namespace app\controllers;

use app\models\News;
use yii\web\Controller;
use yii\web\NotFoundHttpException;

class NewsController extends Controller
{

    /**
     * @param int $id
     * @return string
     */
    public function actionView(int $id):string {
        $model = $this->findModel($id);
        if(!$model instanceof News) throw new NotFoundHttpException("Новость не найдена");
        return $this->render('view',['model'=>$model]);
    }

    public function actionStoryslugView($storyslug):string
    {
        $model = News::find()->andWhere(['alias'=>$storyslug])->one();
        if(!$model instanceof News) throw new NotFoundHttpException("Новость не найдена");
        return $this->render('view',['model'=>$model]);
    }

    private function findModel($id)
    {
        return News::find()->andWhere(['id'=>$id])->one();
    }
}