Re: WSDL 1.2 drops use="encoded"

Robert van Engelen wrote on 03/07/2003 03:48:18 PM:

> 
> 
> Jacek, Rich, & others,
> 
> I am grateful to see a discussion on this topic emerge. From what I've 
> read I believe the move to eliminate "use=encoded" is not a bad 
> decision. The problems seem to outweigh the benefits and SOAP RPC 
> encoding can still be supported with encodingStyle. Having said that 
> though, I do agree with Rich that this move will likely diminish the 
> role of SOAP RPC further and I share his concerns on this matter. The 

Use of SOAP encoding is not a prerequisite for RPC stylized interfaces.
In fact, you don't even need to use the WSDL @style="rpc" to effect
the stylized RPC metaphor in the messages exchanged. It is possible to 
design a schemas that yield instance serializations that are 
indistinguishable
from that of SOAP encoding.

> burden will become to rest on the shoulders of the developers and users 
> of SOAP/WSDL tools. As a result of this, I see some problems that lie 
> ahead to establish cross-platform SOAP interoperability. First of all, 

How so? WS-I's (http://www.ws-i.org/) Basic Profile 1.0 precludes use of 
SOAP 
encoding and WSDL @style="encoded" and WS-I's mission is to enable and 
enhance
cross-platform interoperability. 

> I recall that SOAP RPC has significant merit with respect to object 
> graph serialization and the mapping to an application's data view. I 
> have read that WS is working on an object graph serialization 
> algorithm, but the spec has not appeared yet. Secondly, I believe SOAP 

I believe you meant WS-I, and yes there is a white paper (**NOT** a spec)
that is being developed that describes a number of equally valid
approaches to designing schema-based graph serialization.

> RPC has demonstrated its success in the field, despite that literal 
> encoding appears to be more popular (with popularity based on many 
> non-technicalities). There are certainly many advantages to literal 

The WSDL @style attribute is not being eliminated, only the @use 
attribute.
Indeed, there are some significant advantages to use of literal (XML 
schema)
encoding. Interoperability being one of them.

> encoding. But no one so far has been able to convince me that the 
> removal of "use=encoded" and the move to literal encoding is the right 
> move. Hoping for widespread support for a new schema language to 
> support something that resembles SOAP RPC is a gamble that I won't be 
> happy to wager, not at this early stage with so little evidence. Or am 
> I too pessimistic?

As I indicated before, SOAP encoding has nothing to do with RPC style.
There is no need of "a new schema language", XML Schema serves the purpose
quite effectively.

Development tool vendors are actively working on enhancing their offerings
to improve their support for the "rpc/literal" and "document/literal" WSDL 

styles, my own employer included.

> 
> - Robert van Engelen, Genivia inc., gSOAP development.
<snip/>
> 

Cheers,

Christopher Ferris
Architect, Emerging e-business Industry Architecture
email: chrisfer@us.ibm.com
phone: +1 508 234 3624