RE: Proposed resolution for issue 440

 

> -----Original Message-----
> From: Marc Hadley [mailto:[email protected]] 
> Sent: 06 November 2003 22:24
> To: Martin Gudgin
> Cc: Xml-Dist-App@W3. Org
> Subject: Re: Proposed resolution for issue 440
> 
> On 6 Nov 2003, at 16:40, Martin Gudgin wrote:
> >>
> >>>> MTOM provides one approach to attachments but I fail to 
> see why it 
> >>>> shouldn't be composable with alternative mechanisms.
> >>>
> >>> Because the alternatives are not architecturally sound.
> >>>
> >> That's quite a claim. MIME based systems have been 
> functioning quite 
> >> well without MTOM for some time now...
> >
> > I'm not claiming MIME itself is not architecturally sound. I'm 
> > claiming that using MIME for SOAP in the absence of an 
> infoset view is 
> > not architecturally sound.
> >
> Thanks for clarifying, can you define what you mean by 
> architecturally sound ? Many existing B2B systems do exactly 
> that in, what seems to me, an architecturally sound manner.

To me archtecturally sound means that it composes well with the SOAP
processing model. I don't believe any of the existing attachment
technologies fit the bill. Hence MTOM.

> 
> >>
> >>>> What gets broken in MTOM by allowing this flexibility ?
> >>>
> >>> The fact that the entire message is not an infoset.
> >>
> >> And that's a problem for MTOM because ... ? Where you want 
> the MTOM 
> >> abstraction to apply then you can use the MTOM facilities, 
> where that 
> >> isn't important then you can use something else. Why does 
> it have to 
> >> be all or nothing ?
> >
> > SOAP deals in messages that are infosets. If it's outside 
> the infoset 
> > SOAP doesn't know about it.
> >
> That doesn't require MTOM to actively prevent inclusion of 
> anything outside the infoset. It can just not talk about it.
> 
> Here's an example. I have a SOAP message that includes an 
> MTOM reference to a purchase order in XML format. The 
> purchase order includes an application specific reference to 
> some documentation in the form of a HTML document. The HTML 
> document includes an image. My application wants to bundle 
> the whole lot together and send it. Why should MTOM force me 
> to create an Include reference to the HTML document and 
> associated image inside the SOAP message ?

This is exactly the situation the Representations header is designed to
address.

Gudge


> 
> Marc.
> 
> --
> Marc Hadley <[email protected]>
> Web Technologies and Standards, Sun Microsystems.
>