I'm using search_api/search_api_solr, and would like to be able to exclude certain nodes from being indexed by Solr at all. In looking at search_api.api.php, I see this text:
Please be aware that generally preventing the indexing of certain items is deprecated. This is better done with data alterations, which can easily be configured and only added to indexes where this behaviour is wanted. If your module will use this hook to reject certain items from indexing, please document this clearly to avoid confusion.
I'm just getting into the whole entity API, so it's not so "easy" for me to do this. I'm thinking that he's referring to hook_entity_property_info_alter(), and I've used that to add a property to an entity so it is available as a facet and field available in search results. However, I'm not seeing how to alter the entity so that I can control whether it is indexed by search_api or not. Can someone point me in the right direction?