Minority objection to requiring unique GEDs or required feature to distinguish operations

The WSDL 2.0 Part 1 Last Call Working Draft[1] (will) REQUIRE that if
operations within an interface do not reference unique global element
declarations then a WSDL Feature component MUST be used to indicate how
operations are distinguished 'on-the-wire'. IBM Corp., Microsoft Corp.
and TIBCO Software, Inc. object to this design for several reasons;

1.	It reduces the expressive power of the language.
2.	It forces services to disclose how they distinguish between
operations which leads to tighter coupling between the service and its
consumers than is necessary for interop.
3.	For WSDL authors that want to distinguish between operations
'on-the-wire' then using unique global element declarations for each
message is sufficient.
4.	The mechanism can be trivially circumvented, by defining a
'null' feature that claims to satisfy the requirement but in fact
provides no details on how operations are distinguished. Indeed, someone
has proposed this[2] as a way of 'testing' this particular part of the
specification.
5. 	This restriction makes WSDL 2.0 unable to describe a class of
message exchanges allowed by WS-Addressing.

Please note that IBM Corp., Microsoft Corp. and TIBCO Software, Inc. do
NOT object to WSDL authors being able to write WSDL in such a way that
distinguishing operations is 'obvious', for example by using unique
global element declarations. The objection is to the specification
requiring that WSDL be written in such a way.

Regards

Martin Gudgin, Microsoft Corp.
Amelia A. Lewis, Tibco Software, Inc.
Sanjiva Weerawarana, IBM Corp.

[1] http://www.w3.org/2002/ws/desc/wsdl20
[2] http://lists.w3.org/Archives/Public/www-ws-desc/2004Jul/0336.html

Received on Thursday, 29 July 2004 11:08:02 UTC