Question about Node.JS and XMLSERVICE

My understanding is that XMLSERVICE provides 2 interface options for
various language environments:

1. XMLSERVICE via. ODBC / JDBC stored procedure calls (DB2 Interface).

2. XMLSERVICE via IBM i Apache-CGI calls (REST Web Service Interface).

Since Node.js has an excellent reputation for supporting socket I/O, I'll
assume for the moment that the IBM i implementation makes calls to
XMLSERVICE via the REST Web Service Interface. But does anyone know for
sure?

The flow in my mind goes as follows:

Browser <==> Node.JS HTTP & Application Interfaces <==> IBM i Apache
Interface <==> XMLSERVICE CGI <==> IBM i SQL and PGM resources.

Does that sound about right?

If so, what would be good guidelines for structuring applications under
this flow?

What type of application code do you run under Node.JS?
What type of application code do you run under IBM i programs and
procedures?