PullManager::subscribeOnEvent

protected function subscribeOnEvent(string $eventName, bool $immediate = true): ?string
{
	if($this->isEnabled && !empty($eventName))
	{
		$addResult = CPullWatch::Add(Driver::getInstance()->getUserId(), $eventName, $immediate);
		if($addResult)
		{
			return $eventName;
		}
	}

	return null;
}