RE: NEW ISSUE - message level binding?

Thank you for your comment, which we tracked as LC101 [1].  After long
deliberation the WG decided not to provide out-of-the-box support for
multi-protocol transport bindings.  The issue was thus closed with no
action.  If this resolution is unacceptable, please let us know within
two weeks.

[1] http://www.w3.org/2002/ws/desc/4/lc-issues/issues.html#LC101

> -----Original Message-----
> From: Liu, Kevin [mailto:kevin.liu@sap.com]
> Sent: Wednesday, December 15, 2004 10:27 PM
> To: www-ws-desc@w3.org
> Cc: Jonathan Marsh; Yalcinalp, Umit
> Subject: NEW ISSUE - message level binding?
> 
> I took an action item in our last concall to open a new issue to catch
> the group's discussion around using different transport protocols for
> different messages of a binding operation. The issue was raised in
> discussion on LC50.
> 
> Status Quo
> 
> In the current WSDL2.0 draft, binding type and protocol are specified
> in
> the binding component level,
> 	- the binding component has a "type" property which indicates
> what kind of binding (e.g soap, http, etc) is used.
> 	- The soap binding extension adds a "protocol" property binding
> component to indicate what transport is used.
> 
> Once their values are set, those properties are applied to all the
> operations and messages under that binding, and there is no build-in
> constructs to overwrite them in message level. In other words, by
> design, not only the input and output messages of an operation,  but
> all
> the operations of a binding MUST use same binding type and protocol.
> 
> 
> Issue
> 
> Practically, a typical web service will use the same binding (type,
> transport, etc) for all its input and output messages, but there are
> situations that a service may need to specify different bindings for
> different messages. Here are a few examples,
> 
> - A service may prefer to use different transports for its "in"
> message
> and "out" message, e.g. to receive a request message over SOAP/HTTP
> and
> send the response via SOAP/SMTP.
> - A service may want to specify explicitly some aspect of a transport
> for individual messages.  E.g. while most of the services that use an
> in-out MEP over HTTP may use the same HTTP connection, some services
> may
> prefer use different HTTP connections for the "in" message and the
> "out"
> message.
> - a service that supports ws-addressing replyTo and faultTo may want
> to
> use a different binding for such "re-direct"s. In such cases, they may
> count on WSDL to provide the legal binding candidates such "redirect"
> can use.
> 
> The current spec is not clear/consistent about whether such cases are
> supported by WSDL2.0. Just by looking at the WSDL component model,
> they
> are NOT supported, but mandatory extensions may support them by
> overwriting the binding settings at message level. This inconsistency
> has already caused confusion in the web services community, including
> other W3C working groups.
> 
> 
> Best Regards,
> Kevin

Received on Thursday, 9 June 2005 21:09:04 UTC