Members::extractMemberIds

private function extractMemberIds(array $items): array
{
	$membersIds = [];
	foreach ($items as $item)
	{
		// try to get author id if isset
		if (!empty($item['data']['author']))
		{
			$membersIds[] = $item['data']['author'];
		}
		// try to get responsible id if isset
		if (!empty($item['data']['responsible']))
		{
			$membersIds[] = $item['data']['responsible'];
		}
	}
	return $membersIds;
}