Subject: Issue: PROP_ATTR

From: "Jim Amsden" <[email-masked]>
Date: Wed, 11 Apr 2001 14:08:25 -0400

Boy we've got to put our old thinking caps on for these issues! Anyway, as
 has been pointed out many times in the past, WebDAV does not specify the
 persistence format or semantics of (at least) dead properties, it only
 specifies how properties are marshalled on the wire using the protocol. It
 also does not specify anything but the property name and that its value is
 some XML element. I think WebDAV has the right to define the PROPPATCH
 prop, set, multistatus, etc. elements including the property name and any
 of their associated attributes. But it should not have anything to say
 about the value of the property other then that it is marshalled in well
 formed XML. Clients/servers can use whatever they want for attributes or
 content model for the value element, but must use the attributes (if any)
 and content specified by the WebDAV protocol for the parent of the value.

 If there is some conversion from a property value to some underlying
 storage mechanism, it is the responsibility of the server to figure out
 what to do with the properties value element, attributes, content model,
 and all. Servers may have restrictions about what value types the can
 support, how well they can serialize generic objects in XML, if they use
 RDF, XML Schema, or DTDs to validate, etc. WebDAV shouldn't need to
 concern itself with this. Any attributes on DAV defined elements that are
 not defined in the protocol should be ignored.

  "Jim Whitehead"                                                         
  <[email-masked]>                       To:        "WebDAV WG"         
  Sent by:                         <[email-masked]>                 
  [email-masked]             cc:                            
                                           Subject:        Issue:         
                                   PROP_ATTR                              
  04/10/2001 08:53 PM                                                     

 As mentioned in a previous post, now is the time to start resolving issues
 on the RFC 2518 issues list.  As fate would have it, the first issue on
 the
 list is one that has been contentious in the past. Can we come to
 consensus
 on it now?

 Issue: PROP_ATTR

 Description:

 What is a WebDAV server required to do with XML attributes other than
 xml:lang submitted with a PROPPATCH?  This affects how well WebDAV will be
 able to support RDF, since RDF uses attributes extensively.

 Greg Stein originally raised this issue:

 http://lists.w3.org/Archives/Public/w3c-dist-auth/1998OctDec/0089.html

 See also:

 http://lists.w3.org/Archives/Public/w3c-dist-auth/1998OctDec/0092.html
 http://lists.w3.org/Archives/Public/w3c-dist-auth/1998OctDec/0094.html
 http://lists.w3.org/Archives/Public/w3c-dist-auth/1998OctDec/0095.html

---

From: "Jason Crawford" <[email-masked]>
Date: Fri, 13 Apr 2001 15:12:44 -0400

I agree with Geoff about attributes on live vs dead properties.  (Although
I'm frustrated that the name of the property is mixed in with the value.  I
just don't have an acceptable alternative.)   That is... the attributes of
the property name tag of dead properties (until we find an exception) must
be retained.  For live properties, it's up to the definition of the
property.

J.

------------------------------------------
Phone: 914-784-7569,   [email-masked]

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From: "Jim Amsden" <[email-masked]>
Date: Fri, 13 Apr 2001 16:27:03 -0400

I agree that all attributes should be stored on the property value, but the
DAV:prop element belongs to WebDAV, and WebDAV should define its attributes
as well as content. We should keep attributes off the property name except
those defined by the protocol. Clients should be able to put whatever they
want on the value however they want. And servers should feel free to store
them any way they want.

                    "Clemm, Geoff"                                                                               
                    <[email-masked]       To:     WebDAV WG <[email-masked]>                            
                    om>                      cc:                                                                 
                    Sent by:                 Subject:     RE: Issue: PROP_ATTR                                   
                    w3c-dist-auth-requ                                                                           
                    [email-masked]                                                                                   

                    04/13/2001 02:34                                                                             
                    PM                                                                                           

For dead properties, I don't see the issue wrt storing attribute values
for the root element.  If you are storing attributes on all the nested
elements (as I believe everyone has agreed), it should be trivial
to store it on the root element as well.

For live properties, where the server can take advantage of its knowledge
of the value space for the live property values, then I agree that it
could be an issue.

So I still prefer saying MUST on all attributes of dead properties,
and "as specified in the property definition" for live properties.

Cheers,
Geoff

-----Original Message-----
From: Kevin Wiggen [mailto:[email-masked]]
Sent: Friday, April 13, 2001 12:02 PM
To: Greg Stein; WebDAV WG
Subject: RE: Issue: PROP_ATTR

I agree with Greg et all that "attr2" needs to be stored.

I believe that allowing "attr1" could lead to some interop problems, or we
need to spec this out a little better:

<D:prop>
  <theprop attr1="foo"/>
  <theprop attr1="bar"/>
  <theprop attr2="fee"/>
</D:prop>

Is that legal?  Does the attribute make the property unique?  Does simply
the value of an attribute make it unique?  Or do we (like xmllang) simply
store one set of attributes for a property?

Also how does one use Dasl with attributes on properties?

I would like to see attributes on the property name not be supported.

Kevin

-----Original Message-----
From: [email-masked]
[mailto:[email-masked]]On Behalf Of Greg Stein
Sent: Wednesday, April 11, 2001 1:06 AM
To: WebDAV WG
Subject: Re: Issue: PROP_ATTR

The question isn't about attributes in general, it is about *which*
attributes. Consider the following:

  <D:prop>
    <theprop attr1="foo">
      thevalue
      <subelem attr2="bar"/>
    </myprop>
  </D:prop>

I believe everybody would agree that attr2 gets stored. The real question
is
about attr1. I see that attribute as part of the element that *names* a
property, but it isn't part of the property *value*.

IMO, PROP_ATTR is about defining the boundary between property naming, and
a
property's value.

Cheers,
-g

On Tue, Apr 10, 2001 at 10:58:21PM -0700, Eric Sedlar wrote:
> I agree.  There is no reason not to persist attributes.
>
> > -----Original Message-----
> > From: [email-masked]
> > [mailto:[email-masked]]On Behalf Of Mark A. Hale
> > Sent: Tuesday, April 10, 2001 6:29 PM
> > To: WebDAV WG
> > Subject: RE: Issue: PROP_ATTR
> >
> >
> > Jim:  Thanks for getting the issues list started.
> >
> > I believe that WebDAV must permit properties to have attributes.
> > As you've
> > pointed out, RDF and PRISM do use them extensively.  A server can
reformat
> > the attributes in a subsequent PROPFIND request.  Attrbiutes should be
> > persistent.
> >
> >        Thanks,
> >
> >        Mark
> >
> >
> >
> >
> > > -----Original Message-----
> > > From: [email-masked]
> > > [mailto:[email-masked]]On Behalf Of Jim Whitehead
> > > Sent: Tuesday, April 10, 2001 5:54 PM
> > > To: WebDAV WG
> > > Subject: Issue: PROP_ATTR
> > >
> > >
> > > on the RFC 2518 issues list.  As fate would have it, the first
> > > issue on the

--
Greg Stein, http://www.lyra.org/

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From: "Jim Amsden" <[email-masked]>
Date: Fri, 13 Apr 2001 16:30:28 -0400

I think the usual XML rules should apply. That is, namespace attributes on
the DAV:prop element get applied by default to the value unless the value
provides its own. Clients have complete control of this if it the default
isn't what they want. Servers should be uninvolved in determining semantics
other than following XML rules.

                    "Jason                                                                                   
                    Crawford"            To:     "Kevin Wiggen" <[email-masked]>                        
                    <[email-masked]       cc:     "WebDAV WG" <[email-masked]>                          
                    m.com>               Subject:     RE: Issue: PROP_ATTR                                   
                                                                                                             
                    04/13/2001                                                                               
                    03:28 PM                                                                                 

<<
<D:prop>
  <theprop attr1="foo"/>
  <theprop attr1="bar"/>
  <theprop attr2="fee"/>
</D:prop>
I agree that this is not acceptable unless attr1 and attr2 are namespace
attributes that alter the effective tag name of the property name tags.

This does lead me to another question though.  If in the PROPPATCH call
there are xmlns attributes on the propertyupdate, set, or prop tags that
could potentially affect the tags within the property value, is the server
responsible for collecting those and representing those in PROPPATCH
responses?   Or should we require that the client put any xmlns attributes
that it cares about on the propertyname tag and within?

J.