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Re: Second level xs:import

From: Prasad Yendluri <pyendluri@webmethods.com>
Date: Wed, 04 Feb 2004 14:04:11 -0800
Message-ID: <40216C5B.7020908@webmethods.com>
To: www-ws-desc@w3.org
I am in favor of clarifying this via some explanatory text in the spec. 
This is a typical confusion and the members of this WG itself have gone 
around this topic several times already, each time resulting in long 
winded threads. I am sure many WSDL users that are novice and other that 
are though beyond novice,  yet to achieve expert level :) in schema 
usage would find this helpful. When this issue shows up again we can 
simply point to the right spot in the spec or say RTFS.

Prasad

-------- Original Message --------
Subject: 	RE: Second level xs:import
Resent-Date: 	Wed, 4 Feb 2004 16:49:31 -0500 (EST)
Resent-From: 	www-ws-desc@w3.org
Date: 	Wed, 4 Feb 2004 13:49:21 -0800
From: 	Yaron Goland <ygoland@bea.com>
Reply-To: 	<ygoland@bea.com>
To: 	'Amelia A Lewis' <alewis@tibco.com>, 'Roberto Chinnici' 
<Roberto.Chinnici@Sun.COM>
CC: 	<www-ws-desc@w3.org>

While I can understand the motivation I would submit that the behavior is
not intuitive. At a minimum it would seem appropriate to include an
explanation of the behavior so that users and implementers will understand
what is going on.

I therefore move that the following text be added to the end of the first
paragraph in section 3.1.1 as defined in the 2004/01/06 22:48:24 draft: The
prohibition against directly referring to components imported by schemas
that are themselves imported/included by WSDL is intended to force WSDL
definitions to directly refer to the schema definitions of all components
used by that WSDL. Requiring direct references to imported schema components
is felt to provide a cleaner WSDL definition. While this restriction may
make it look as if the same schema is being imported multiple times it is
not actually so. For example, Schema A imports Schema B which has components
needed by Schema A's definitions. A WSDL that imported Schema A is free to
reference any component in Schema A but the components in Schema B are,
effectively speaking, invisible to the WSDL. While Schema A can refer to
Schema B components, the WSDL cannot. If the WSDL needs to directly
reference schema B components then the WSDL must explicitly import Schema B.
Only when Schema B is explicitly imported by WSDL will Schema B's components
become visible to the WSDL.

		Yaron

> -----Original Message-----
> From: www-ws-desc-request@w3.org [mailto:www-ws-desc-request@w3.org]On
> Behalf Of Amelia A Lewis
> Sent: Wednesday, February 04, 2004 7:52 AM
> To: Roberto Chinnici
> Cc: www-ws-desc@w3.org
> Subject: Re: Second level xs:import
>
>
>
> Good analogy.  +1.
>
> On Tue, 03 Feb 2004 17:34:57 -0800
> Roberto Chinnici <Roberto.Chinnici@Sun.COM> wrote:
>
> > It doesn't have anything to do with inheritance, it's
> really all about
> > modules.
> >
> > An xsd:import means "I'm going to use some top-level components from
> > this namespace, please make them available". Perhaps those
> components
> > need in turn to use components from yet another namespace, but why
> > should I see them? They are an implementation detail really.
> >
> > Or, to use a programming language analogy, xsd:import and
> wsdl:import
> > are more like Java import, not C #include. And that's the correct
> > definition, IMHO.
> >
> > Roberto
> >
> >
> > Yaron Goland wrote:
> > > If I import a Schema file from namespace Foo and the Schema File I
> > > imported itself imports a schema file from namespace Bar then
> > > effectively the WSDL file has imported namespace Bar as well and
> > > should be free to reference Bar. The inheritance chain is
> clear. The
> > > namespaces are all explicitly declared. What's the problem?
> > >
> > >
> > >>-----Original Message-----
> > >>From: Martin Gudgin [mailto:mgudgin@microsoft.com]
> > >>Sent: Friday, January 30, 2004 8:18 AM
> > >>To: ygoland@bea.com; Amelia A Lewis; David Orchard
> > >>Cc: www-ws-desc@w3.org
> > >>Subject: RE: Second level xs:import
> > >>
> > >>
> > >>The *design* limitation, was that schema wanted people to be
> > >>*explicit*
> > >>about namespaces they wanted to use. So, in order to reference
> > >>components in namespace foo, a schema MUST have an import for
> > >>namespace
> > >>foo ( or itself be a schema for namespace foo ).
> > >>
> > >>I think it is a reasonable design decision to make for WSDL too.
> > >>
> > >>Gudge
> > >>
> > >>
> > >>>-----Original Message-----
> > >>>From: www-ws-desc-request@w3.org
> > >>>[mailto:www-ws-desc-request@w3.org] On Behalf Of Yaron Goland
> > >>>Sent: 26 January 2004 17:30
> > >>>To: 'Amelia A Lewis'; 'David Orchard'
> > >>>Cc: www-ws-desc@w3.org
> > >>>Subject: RE: Second level xs:import
> > >>>
> > >>>
> > >>>While I can appreciate the wisdom in re-use, re-use should
> > >>>only be done with open eyes and full understanding. Do we
> > >>>know the technical reason why the restriction is there? If
> > >>>not then we should either find out or remove the restriction.
> > >>>	Thanks,
> > >>>		Yaron
> > >>>
> > >>>
> > >>>>-----Original Message-----
> > >>>>From: www-ws-desc-request@w3.org
> > >>>
> > >>>[mailto:www-ws-desc-request@w3.org]On
> > >>>
> > >>>>Behalf Of Amelia A Lewis
> > >>>>Sent: Monday, January 26, 2004 12:05 PM
> > >>>>To: David Orchard
> > >>>>Cc: www-ws-desc@w3.org
> > >>>>Subject: Re: Second level xs:import
> > >>>>
> > >>>>
> > >>>>
> > >>>>Because that works the same way that schema import does,
> > >>
> > >>and that's what it's modeled on.
> > >>>>
> > >>>>Amy!
> > >>>>On Jan 26, 2004, at 2:54 PM, David Orchard wrote:
> > >>>>
> > >>>>
> > >>>>>Why is it illegal to reference items that are included in an
> > >>>>>imported/included schema vis xs:import? (per section 3 of part 1)
> > >>
> > >>>>>Cheers,
> > >>>>>Dave
> >
>
>
> --
> Amelia A. Lewis
> Architect, TIBCO/Extensibility, Inc.
> alewis@tibco.com
>
Received on Wednesday, 4 February 2004 17:04:17 UTC

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