You are looking for an Interface Definition Language (IDL) expressed in
XML. There are now a few of them floating around.
webMethods has one called WIDL (Web IDL). It is an 80/20 IDL -- 80% of the
functionality of conventional IDLs with 20% of the complexity. It can't
express any CORBA interface, but it can express about 80% of the ones that
show up in practice. You can learn a little about this IDL from this URL:
http://www.webmethods.com/xml/widl_wp.html
Unfortunately, this URL is a bit dated and does not distinguish between
WIDL specifications and WIDL mappings. A WIDL mapping is a way to
implement a specification so that the interface wraps up an HTML or XML web
site.
You might instead read a chapter I wrote Charles Goldfarbs'
_The_XML_Handbook_. The chapter is titled "WIDL and XML RPC." For an
example application of WIDL with XML RPC, see the chapter titled "Supply
chain integration."
John Tigue of Datachannel also developed an IDL in XML. It's part of a
well-thought-out framework of XML technologies for RPC. You can find his
work at this URL:
http://www.w3.org/Submission/1998/07/
His IDL and RPC format are intended to serve as a superset of both CORBA
and DCOM. An amazing feat. It quite a bit more complicated than WIDL, but
you'll probably want it if your problem space falls into the 20% area that
WIDL is missing.
-- Joe Lapp, Senior Engineer | jlapp@webMethods.com webMethods, Inc. | Voice: 703-267-1726 http://www.webMethods.com | Fax: 703-352-0370