This question has been answered by multiple community members. See the first response.
<?php /* only operate on new resources */ if ($mode != modSystemEvent::MODE_NEW) return; $parentId = $resource->get('parent'); $res = $parentId; /* top level documents are not regarded! */ if ($parentId > "0") { $parentResource = $resource->getOne('Parent'); $groups = $parentResource->getMany('ResourceGroupResources'); foreach($groups as $name => $grpObject) { $resGrpId = $grpObject->get('document_group'); $success = $resource->joinGroup($resGrpId); } }
foreach($groups as $group) { $resGrpId = $group->get('document_group'); $success = $resource->joinGroup($resGrpId); }