The other key concept is that after some clients upload to a specific sub path area that is authorized for uploads, the clients can use a query string option on

The other key concept is that after some clients upload to a specific sub path area that is authorized for uploads, the clients can use a query string option on a GET request to list out files in that area. I suppose the website owner could have one or more administrative javascript sessions running that will periodically poll this area as just described, to process the data and upload a more compact listing for clients to retrieve.