Rest::getLangField

private function getLangField($appId, $fieldName)
{
	$fields = $this->getAppLangFields($appId);
	if (!$fields)
	{
		return '';
	}

	$fieldLangs = $fields[$fieldName];
	if (isset($fieldLangs[LANGUAGE_ID]))
	{
		return $fieldLangs[LANGUAGE_ID];
	}
	else
	{
		$defaultLang = Loc::getDefaultLang(LANGUAGE_ID);
		if (isset($fieldLangs[$defaultLang]))
		{
			return $fieldLangs[$defaultLang];
		}
	}
	return $fieldLangs['**'];
}