xml-dev - Re: Microsoft's DISCO proposal and XML packaging

[Matt Sergeant <matt@sergeant.org>]

On Tue, 11 Jul 2000, Edd Dumbill wrote:

> I've just read http://msdn.microsoft.com/xml/general/disco.asp
> "Draft: Discovery of Web Services (DISCO)"
> 
> Some thoughts immediately spring to mind, and most of them center around
> the uneasy feeling that wheels are being reinvented. For this reason
> I'd like to draw the attention of the list to the draft and get some
> opinions on it.  Unfortunately, the authors aren't named on the document
> itself. I have a couple of nits, which I'll mention here, but the second
> half of this message contains what I view to be the more important
> thoughts that DISCO provokes.
> 
> * the proposals for embedding metadata etc. seem rather similar to RDF.
>   Any comments on why RDF is not used here?
> 
> * the mechanisms for finding the discovery documents over HTTP seem a
>   little odd to me (eg. putting a discovery document in a stylesheet).
>   I'm certainly no expert in this domain, which is another reason I'm
>   inviting comment.

Well they've completely bastardised the spec on this one. For starters,
even though browsers don't seem to do it yet, they should be offering up
the list of alternate stylesheets to be able to process the document
differently. Then by using text/xml as the type this tells you absolutely
squat about the actual resource. Then they don't specify that you _must_
have a title="..." psuedo-attribute if you specify
alternate="yes" (although the spec is very unclear on that point). And
then with the HTML version, they've used <LINK> with rel="alternate",
which is reserved for stylesheet processing. If you want some other use,
the HTML spec even details using it for "Next" and "Prev", why not
"Disco"? But the "flying on top of stylesheets" has to stop. The discovery
document isn't a stylesheet, its not even really a processing
instruction. Its a link, pure and simple. Can you spell XLink, boys and
girls?

And it should use RDF.

Aside from all that, I don't have a problem with it ;-)

-- 
<Matt/>

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