[Pipet Devel] XML-RPC

[Brad Chapman]

Tony Rossini wrote:
> I'm slowly going over the archive of the mailing list for this 
project
> -- havn't seen XML-RPC mentioned, but lots of ties to projects where
> it should've fit.
> 
> Is this under consideration as a mechanism for constructing glue or
> for serialization?

    Hi, I should butt in on this discussion since I'm probably the one 
who pushed for CORBA the most out of anyone. I should also preface 
this all by saying that I like CORBA *a lot* and so everything I say 
is probably baised by this :-)
    I've spent some time looking at XML-RPC and SOAP, and from all of 
my impressions, it seems like they are primarily designed to be used 
in web applications. This seems to be kind of reflected in the 
languages for which XML-RPC implementations are available: Java, 
Python, Perl, PHP, etc. By contrast, CORBA is designed for application 
usage. This is why I sort of immediately invision CORBA as being 
better suited for use for Piper. 

> No, it (speed) is quite important.  I'd personally like to stream
> megabytes of data (in a statistical, "flat-file"-ish sense) and
> process it at the same time.

I don't know if speed is really an issue many people know much about 
yet. There was a big argument on comp.object.corba about SOAP versus 
CORBA speed issues, and it seemed like most of the discussions was 
more opinions and not hard facts. XML-RPC and SOAP are relatively new 
(compared to CORBA), so it is difficult to say how well they will 
scale right now. But I guess I can't really say that XML based 
protocols are slower than IIOP.

> The only rationale for XML-RPC is "simplicity".  We'll keep it in
> quotes, since I'm saying that out of context and it implies a set
> decision-making criteria behind it.

You are right, XML-RPC is probably simpler to start with, but as you 
mention, it is hard to say how it will keep this simplicity as an 
application grows. Although CORBA is big and harder to get into at 
first, I think it contains tons of hooks for just about every 
situtation, which might make it ultimately simpler over time. Hard to 
say, I guess.
 
> Again, I'm not interested in baiting, just finding out what has been
> explored/considered, and what the framework is. 

Yeah, I don't think the whole situation has been completely hashed out 
on the list. CORBA and XML based communication protocols seem to me to 
be "somewhat" interchangable. Probably personal preference has played 
the largest role in choosing CORBA for the communication protocol for 
Piper. I guess the largest voice against CORBA has been because of the 
learning curve to get started with it. However, I have found it really 
nice for development (very flexible to API changes etc), so once you 
are over the learning curve, it can be very nice.

> We (one of my "affiliations") are looking into wet-lab
> informatics/data processing, 

This is actually what I want to use Piper for myself, so it better be 
able to handle this :-). My grad research is all wet-lab based, and I 
would like Piper to help enhance the things I'll be doing there. The 
sooner it is implemented, the better it'll be for me as well!

Brad