So getting a list of content by type and place is a simple call to the /contents service: see Get Contents > filter=place(/api/core/v3/places/xxxx) + filter=type(xxxx)
Getting attachments can only be done at a content level, and since attachments can be on any content type... It makes sense to query all content and check the attachments resource for details...but this can be admittedly expensive to constantly due.
If you want, you can set up a webhook to post to an external service and you could analyze new content once it is edited/created.
If you are looking to store these files, you can look into an external storage provider which would store binary files on creation in an external system and make them available in Jive as if they are native, but that is a more detailed integration ... And also may be a lot more than what you are wanting.
Hope that helps.