How to set up a REST service to accept streaming xml data and jrxml file as input to generate PDF stream as output?

Newbie question:

We have an application that can generate a stream of XML data. It can also select the right Jasper template (based on company, user, etc.) and stream that.

How do I go about exposing a REST service on the Jasper Server that can process these two and then generate a PDF as the output to be streamed back?

[I am trying to search through various forums to see if this has been asked/answered before - so apologies in advance if this is a repeat.]