W3C home > Mailing lists > Public > public-ws-semann@w3.org > April 2006

Re: issue: Identifying type of model

From: Joel Farrell <joelf@us.ibm.com>
Date: Fri, 21 Apr 2006 09:55:01 -0400
To: Jacek Kopecky <jacek.kopecky@deri.org>
Cc: SAWSDL WG <public-ws-semann@w3.org>
Message-ID: <OFB8CEA4A3.0AB6A4A9-ON85257157.004B0C90-85257157.004C7330@us.ibm.com>

Thanks Jacek,

Then I think we can keep the spec as it is - as in option  number 1.  On
the sub-issue you raised, the spec does point to a specific element within
the model and, indeed, the whole file will have to be read in order to
resolve it.  I think this clears the way for the support of a list of
references directly in the WSDL modelReference attribute.

Regards,
Joel

public-ws-semann-request@w3.org wrote on 04/19/2006 09:16:20 AM:

>
> Hi Joel,
>
> your issue is now logged as issue 3 at
> http://www.w3.org/2002/ws/sawsdl/issues/#x3
>
> I feel there is a hidden sub-issue here:
>
> What are we identifying in modelReference - a thing, a part of a model
> (like a class in OWL or concept in WSML or something similar) or a whole
> model (an OWL file, a WSML file etc.)? I believe the current draft leans
> towards the former, i.e. a thing defined by the model. If that's the
> case, then a thing can be described using multiple languages (like Eric
> was pointing out yesterday with some kind of indirection) and so SAWSDL
> could have a hard time actually saying what language is used for a
> particular pointer.
>
> Even if the URI identifies a part of the model, resolving it can still
> lead to the description of the full file, for example
> http://example.org/ontology#class identifies a class, but when resolving
> this, the client will actually read http://example.org/ontology
>
> Assuming here that modelReference does identify a thing (a part of a
> model), I would go with the intent of your option 1 - our spec doesn't
> say anything, the client will have to see it to know if it can
> understand a particular modeling language; this will allow multiple
> languages describing the same thing and the client choosing whatever it
> understands best.
>
> Please see more comments below.
>
> Jacek
>
> On Tue, 2006-04-18 at 15:26 -0400, Joel Farrell wrote:
> > Hi All,
> >
> > The modelReference attribute points to a concept in some semantic model
and
> > SAWSDL is independent of the language used to express that model.  The
> > question is: Do we need to identify the language as part of the
annotation?
> > In other words, can a tool that is processing the WSDL file determine
what
> > kind of a model (OWL, WSML, ODM...) is at the URI pointed to by the
> > modelReference?  I can think of three answers:
> >
> > 1. Yes, it can read the document and see if it can recognize it.  This
> > would require no change to our spec.
>
> The web also gives us things like media types so the client can do an
> HTTP HEAD on the URI and see what media type it has, and this should say
> whether it's an OWL file, WSML file or something else.
>
> > 2. Yes, but only if the URI includes a file extension like ".owl".   Is
> > this a reasonable restriction? If so, our spec need not change.
>
> I don't think the Web people would like this, URIs should be mostly
> opaque to the users, and it's good practice not to include .owl (or
> similar things) in URIs in fact, so that the URI needn't change when the
> language choice changes.
>
> > 3. No, it needs to be explicitly stated.  This could be done via a
> > modelType attribute that pairs with the modelReference attribute or it
> > could be specified once per interface or once per WSDL document
> > (definitions).  If something like this is needed, it will have an
> > implication if we decide that a modelReference can be a list of
references.
> >
> > The spec currently does not restrict a WSDL file from using a different
> > type of model for each individual annotation. (It is silent on the
issue.)
> > Once this issue and the multiple models per modelReference issue is
> > resolved, the spec will have to be explicit about this.
> >
> > Regards,
> > Joel Farrell
> >
> >
>
>
Received on Friday, 21 April 2006 13:55:22 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 17 April 2012 12:14:26 GMT