Re: [IBMiOSS] RPG parameters to Python and back

On Sat, 2 Jun 2018 at 14:07, John Yeung <gallium.arsenide@xxxxxxxxx> wrote:

On Fri, Jun 1, 2018 at 5:30 PM, Buck Calabro <kc2hiz@xxxxxxxxx> wrote:

I'm looking for options to be able to have an RPG program fire off
these Python 'services', have them work with the web service, and pass
the results back to RPG.

Do you need something "tighter" than dropping off the return values in
a stream file or database table?

I'd like something synchronous.

Here's one use case:
Customer calls in, customer care agent answers the phone. Customer
provides info for agent to look her up in our existing RPG
application. On the screen today are name, contact info, history -
all the usual information that's held on a midrange database. What we
want to do is add an indication whether there are specific documents
in the vendor's document system for this specific customer.
Notionally, it would happen in the RPG code at the same place the
CHAINs happen to get the DB2 information.

Ultimately, I think if you're going to rely on Python (or other
technologies of a similar nature, such as Node.js, Ruby, PHP, etc.)
then you will have to accept that "calling" and "retrieving values"
are two separate steps performed by the caller.

Ah well.

If you really want that immediacy and "single-step" feel of a call
with output parameters or return value, you have to use something
other than Python.

That's why I asked the question :-)

For green-field (not green-screen!) programming, of course just using
Python throughout would be a good option. (And you *can* plumb a *PGM
or *SRVPGM into surrounding Python quite cleanly.)

I've heard of this green field. It's where the unicorns play fetch
with Elvis, right?
:-)

--buck