Allowing specific users to see/add images related to a specific site group?

[pv2b]

Hello!

I'm looking to use the permission system to allow access to a specific site group, and objects related to that. Unfortunately, I'm running into a bit of a snag when it comes to Image Attachments.

I can't figure out how to write a query to say "image attachments, that belong to a rack, that belongs to a site". Let alone to add a site group into the mix.

I should be something like this:

{"object_type__model": "dcim.rack", "parent__site__group__name": "FOO"}

But that leaves me with this validation error:

Invalid filter for <class 'extras.models.models.ImageAttachment'>: Field 'parent' does not generate an automatic reverse relation and therefore cannot be used for reverse querying. If it is a GenericForeignKey, consider adding a GenericRelation.

Is this simply a limitation of the current object model of Netbox, i.e. the database isn't set up to handle this type of query, or is there some magic incantation I can use here?

Thanks in advance.