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Re: RPC Style Issues (3)

From: Umit Yalcinalp <umit.yalcinalp@oracle.com>
Date: Sun, 02 Nov 2003 14:11:34 -0800
Message-ID: <3FA58116.1020207@oracle.com>
To: Jonathan Marsh <jmarsh@microsoft.com>
Cc: Jeffrey Schlimmer <jeffsch@windows.microsoft.com>, jacek.kopecky@systinet.com, sanjiva@watson.ibm.com, tomj@macromedia.com, www-ws-desc@w3.org


Jonathan Marsh wrote:

>Umit, it sounds like you are disagreeing with the basic premise of Web
>services interoperability (interop is based on well-defined messages
>going back and forth, not on the compatibility of the programming models
>on each end.)  It's hard for us to imagine that you really mean that.
>
Jonathan, of course having well-defined messages going back and forth is 
a necessary condition for interoperability. The schema definitions 
required to define the allowable messages. (The hints are there to 
provide a uniform mapping to support the rpc use case in environments 
for which that is important.)

>Perhaps you could really spell out what change you are asking for.
>
The proposed change to the current WD was spelled out in [1].

However, based upon the last con call and recent email discussion, I've 
crisped it up a bit so that hopefully no one will be confused as to what 
the proposal is. Rather than paste it in here, I just posted it to the 
list completing my action
item also. See [2].

Cheers,

-- umit

[1] http://lists.w3.org/Archives/Public/www-ws-desc/2003Oct/0057.html
[2] http://lists.w3.org/Archives/Public/www-ws-desc/2003Nov/0007.html

>
>  
>
>>-----Original Message-----
>>From: www-ws-desc-request@w3.org [mailto:www-ws-desc-request@w3.org]
>>    
>>
>On
>  
>
>>Behalf Of UMIT.YALCINALP@ORACLE.COM
>>Sent: Friday, October 31, 2003 11:19 AM
>>To: Jeffrey Schlimmer; jacek.kopecky@systinet.com
>>Cc: sanjiva@watson.ibm.com; tomj@macromedia.com; www-ws-desc@w3.org
>>Subject: Re: RE: RPC Style Issues (3)
>>
>>    
>>
>>>Don't forget that the RPC style is not needed for interop since it
>>>      
>>>
>does
>  
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>>>not affect the messages that are exchanged. It is a means to convey
>>>intended programming model and should be designed to be sufficient
>>>      
>>>
>for
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>>>that purpose.
>>>      
>>>
>>I disagree with this statement.
>>
>>RPC style has two distinct requirements:
>>
>>-- Schema requirements that describe what it means to be a conformant
>>    
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>WSDL
>  
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>>with respect to this style The schema requirements define the
>>    
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>structure of
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>>the messages, (i.e) whether it should only contain local elements,
>>    
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>etc.
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>>-- Programming hints.
>>
>>This is why I made the proposal [1] to divide the rules into two
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>sections.
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>>You are putting these two requirements as if both talk about
>>    
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>programming
>  
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>>hints, they don't. The first set of rules define what the schema
>>conformance rules are.
>>
>>I would agree with Sanjiva (this is verbatim from my IRC log Sanjiva,
>>    
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>i
>  
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>>hope you don't disagree quoting you here again ;-)). "Interoperability
>>    
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>is
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>>quaranteed with the schemas, not the programming model."
>>
>>This is why I propose the rules are defined as such, in two separate
>>sections.
>>
>>For example, if I were to publish a WSDL with the RPC style URI, but
>>    
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>do
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>>not follow the rules in the first section, a client who makes use of
>>    
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>this
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>>style may not be able to process the schema because it is expecting
>>    
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>the
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>>messages to be formatted in a certain way and they are not. That is
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>why it
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>>affects interoperability. I would not know what to do if the
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>complexType
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>>contained attributes, or a choice, etc.
>>
>>IMHO, David explained it quite well during the telcon. We should be
>>talking about what conformance means. From our perspective, a WSDL is
>>    
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>not
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>>conformant if it uses the style URI but did not follow the schema
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>rules.
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>>Arthur's checker should be able to barf on such a WSDL.  This has
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>nothing
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>>to do about how one further processes the message, but is necessary
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>for
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>>those who would make use of this style.
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>>Further, if you want to follow the hint or use DOM to represent your
>>message, conformance can not talk about it unless we get into the
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>business
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>>of describing how each respective language such as Java, C++, C# must
>>    
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>be
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>>handling RPC style. There are specs for that and conformance suites
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>that
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>>are tailored. I am sure some members of this community will not be
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>very
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>>receptive if we were to get into that business.
>>
>>What we are proposing here is the message conformance. Lets not mix it
>>with the intended programming model that is further described in the
>>second set of rules.
>>
>>This is the same analogy to using a MEP which is defined to use a
>>    
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>message-
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>>triggers-fault rule but mistakenly uses faults incorrectly wrt
>>directionality. I say this is a non conformant WSDL, regardless of you
>>know how to implement this MEP or not.
>>
>>Cheers,
>>
>>--umit
>>
>>
>>[1] http://lists.w3.org/Archives/Public/www-ws-desc/2003Oct/0057.html
>>    
>>
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>
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-- 
Umit Yalcinalp                                  
Consulting Member of Technical Staff
ORACLE
Phone: +1 650 607 6154                          
Email: umit.yalcinalp@oracle.com
Received on Sunday, 2 November 2003 17:11:47 GMT

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