[XML-SIG] RE: SOAP for Python
Wed, 02 May 2001 22:40:28 -0600
> > Until then, I rely on the fact that section 5 is explicitly optional. There
> > is no requirement for a SOAP implementation to use the SOAP serialization.
> Technically right, but it would be *very* surprising and upsetting to
> folks who naively used the 4SS implementation to talk to other web
> services. It might even cause them to spit venom at you.
After I sent my last message another thought struck me. You use the term "Web
services" above. Probably I have to understand what you mean by that before I
understand why you think it would be surprising and upsetting to have SOAP
systems that don't implement section 5.
The only reason everyone would want to "just stick to section 5" is for
"transparent" API-type calls. RPC all over again. Basically CORBA with
SOAP/HTTP over the wire rather than CDR/IIOP.
But what on earth is the use of such a thing? Why not just use CORBA or DCOM
or RMI, all of which are vastly more efficient than SOAP and can claim more
pedigree and interop?
The answer is simple: because such tightly-coupled systems do not survive the
boundary from one business technology and process to another. Crossing such a
boundary requires loosely-coupled systems, and that is the only reason there
is any relevance to the buzzword "Web services".
Successful Web services will be message-oriented, loosely coupled systems with
a great deal of flexibility that is handled through metadata management.
Whether you're in the ebXML camp or the UDDI camp, you had better be taking
those tModels, WSDL bindings and CPPs seriously, because if you just blindly
write code that assumes that, say everyone uses SOAP serialization, you will
be doing commerce with only a fraction of your brave new market.
This is why it was utter silliness for section 5 not to have been broken out
of SOAP transport into a separate spec. It encourages people to wrongly
assume that SOAP implies section 5, and thereby condemn themselves to
reinventing the RPC wheel all over again.
And I'll note that I'm not alone in this sentiment. In past SOAP debates on
XML-DEV, no lesser figures than Tim Bray and David Megginson have expressed
similar annoyance at the conflation of transport and content model that mars
So do I think it's realistic that section 5 will be put in its place before XP
emerges? Absolutely. And in the unlikely event that this doesn't happen, Web
services will pretty much drown in its own unfulfilled promises.
Uche Ogbuji Principal Consultant
firstname.lastname@example.org +1 303 583 9900 x 101
Fourthought, Inc. http://Fourthought.com
4735 East Walnut St, Ste. C, Boulder, CO 80301-2537, USA
Software-engineering, knowledge-management, XML, CORBA, Linux, Python