CRestProvider::getFeature

static function getFeature($params, $n, CRestServer $server)
{
	$params = array_change_key_case($params, CASE_UPPER);
	$result = [
		'value' => '',
	];
	if (empty($params['CODE']))
	{
		throw new RestException(
			'CODE can't be empty',
			'CODE_EMPTY',
			CRestServer::STATUS_WRONG_REQUEST
		);
	}

	if(BitrixMainModuleManager::isModuleInstalled('bitrix24') && Loader::includeModule('bitrix24'))
	{
		$result['value'] = BitrixBitrix24Feature::isFeatureEnabled($params['CODE']) ? 'Y' : 'N';
	}
	else
	{
		foreach (GetModuleEvents('rest', 'onRestGetFeature', true) as $event)
		{
			$eventData = ExecuteModuleEventEx(
				$event,
				[
					$params['CODE'],
				]
			);
			if (is_array($eventData))
			{
				if ($eventData['value'] === true || $eventData['value'] === 'Y')
				{
					$result['value'] = 'Y';
				}
				else
				{
					$result['value'] = 'N';
				}
			}
		}

		if (empty($result['value']))
		{
			$result['value'] = LANGUAGE_ID . '_selfhosted';
		}
	}

	return $result;
}