For an example of RDF being exchanged between a server and a client, you can test

https://search.datao.net/beta/?q=barack%20obama

Open your javascript console, and hover the results on the left hand side of the page with your mouse. The console will display which RDF message triggered the viz in the center of the page.

Update: you may want to FIRST select the facet "DBPedia" at the top of the page, for more meaningful messages exchanged.

Update2: the console does not do syntax higlighting, so here is the highlighted RDF https://datao.net/ttl.jpg linked to the 1st item of " https://search.datao.net/beta/?q=films%20about%20barack%20ob... "