user.php

См. документацию.

<?php
namespace Bitrix\MessageService\Context;
 
use Bitrix\Main\Loader;
 
class User
{
    public static function getId()
    {
        $user = static::getUser();
        return $user? (int)$user->getId() : 0;
    }

    public static function getUser()
    {
        return isset($GLOBALS['USER']) && $GLOBALS['USER'] instanceof \CUser ? $GLOBALS['USER'] : null;
    }
 
    public static function isAdmin()
    {
        $user = static::getUser();
 
        if ($user && $user->isAuthorized())
        {
            return (
                $user->IsAdmin()
                ||
                Loader::includeModule('bitrix24') && \CBitrix24::isPortalAdmin($user->getId())
            );
        }
 
        return false;
    }
}