To prevent search engines from indexing identical content across your sites and punishing you for “duplicate content”, you can set the canonical tag on your sub-sites to the URL of the content on your source site.
To get the URL of the entity on the source site, you can use:
// The following snippet assumes that a node entity is available as a $node variable // that you want to get the source URL for. $source_url = NULL; $status = \Drupal\cms_content_sync\Entity\EntityStatus::getInfosForEntity( $node->getEntityTypeId(), $node->uuid() ); foreach ($status as $candidate) { if ($candidate->isSourceEntity()) { continue; } $source_url = $candidate->getSourceUrl(); if ($source_url) { break; } } // The variable $source_url will now be the full URL to the content on the source site // or NULL if the node wasn't pulled from another site- in this case you can just use the // local URL of the node instead.
Please note that path aliases are not used for the source entity URL as they may change.