Pimcore\Tool::isValidLanguage PHP Метод

    public static function isValidLanguage($language)
    {
        $languages = self::getValidLanguages();
        // if not configured, every language is valid
        if (!$languages) {
            return true;
        }
        if (in_array($language, $languages)) {
            return true;
        }
        return false;
    }

 /**
  * Get user preferred locale.
  *
  * @return string|null
  */
 protected function getPreferredLanguage()
 {
     if (!isset($_COOKIE[self::LANG_PARAM_NAME])) {
         return null;
     }
     $lang = $_COOKIE[self::LANG_PARAM_NAME];
     if (Tool::isValidLanguage($lang)) {
         return $lang;
     }
     return null;
 }