Setting frontendUrlManager

common-main.php

<?php
// common/config/main.php
return [
    'components' => [
        'frontendUrlManager' => [
            'class' => 'yii\web\UrlManager',
            'baseUrl' => '',
            // https://github.com/LAV45/yii2-settings/tree/master/examples/ProjectConfiguration
            //'hostInfo' => config('frontend_url', 'https://site.com'),
            'hostInfo' => 'https://site.com',
            'scriptUrl' => '/index.php',
            'enablePrettyUrl' => true,
            'showScriptName' => false,
            'rules' => require(Yii::getAlias('@frontend/config/url_rules.php')),
        ],
    ],
];

frontend-main.php

<?php
// frontend/config/main.php
return [
    'components' => [  
          'urlManager' => [
            'enablePrettyUrl' => true,
            'showScriptName' => false,
            'rules' => require __DIR__ . '/url_rules.php',
        ],
    ],
];

SiteController.php

<?php
// backend/controllers/SiteController.php

namespace backend\controllers;

class SiteController extends Controller
{
    public function actionIndex()
    {
        Yii::$app->frontendUrlManager
            ->createAbsoluteUrl(['/news/view', 'id' => 123]); // => https://site.com/news/123
    } 
}

url_rules.php

<?php
// frontend/config/url_rules.php
return [
    'news' => 'news/index',
    'news/<id:\d+>' => 'news/view',
];