Subject: RFC2518 bis, attributes on property names -- in or out?

From: "Lisa Dusseault" <[email-masked]>
Date: Wed, 27 Nov 2002 18:38:19 -0800

I heard from at least one implementor (Joel Soderberg) that random
attributes on property names should not be stored "as part of" the
property.  This makes it more complicated to marshall the property again
when responding to a PROPFIND request.  Attribute namespaces may be
difficult here. What namespace are the attributes in?  What if the
attribute on the property name is a namespace declaration -- does that
have to be preserved *in that location*?

Another consideration is that we may want to reserve attributes on the
property name for meta-information *about* the property (like data
types).  That kind of information isn't part of the *value* of the
property, but it may be used to figure out how to treat the property now
or later.  An implementation could safely ignore attributes it didn't
understand.  

RFC2518 says "Language tagging information in the property's value (in
the "xml:lang" attribute, if present) MUST be persistently stored along
with the property, and MUST be subsequently retrievable using PROPFIND."
I believe the spec is silent about other attributes.

In RFC2518bis, we got more specific about what makes up the value of a
property:
   "The value of a property consists of attributes on the property name 
   element, language attributes which are scoped to the property, 
   namespaces which are used in the property name element or its 
   children, and child elements including text.  The server MUST 
   persistently store this information and reconstruct it in PROPFIND 
   responses.   "

Now that objections have been raised, who feels strongly for one side or
another?

Lisa

---

From: "Julian Reschke" <[email-masked]>
Date: Thu, 28 Nov 2002 10:10:55 +0100

> From: [email-masked]
> [mailto:[email-masked]]On Behalf Of Lisa Dusseault
> Sent: Thursday, November 28, 2002 3:38 AM
> To: Webdav WG
> Subject: RFC2518 bis, attributes on property names -- in or out?
>
>
>
>

I don't understand that part of the question. The namespace of an attribute
is defined by the "Namespaces in XML" recommendation. There's no ambiguity
here.

> have to be preserved *in that location*?

Back last year, I wrote down a precise definition of what I think needs to
be persisted. This is not part of it.

> or later.  An implementation could safely ignore attributes it didn't

This is a no-brainer. Attributes can be put into namespaces to disambiguate
them. The specific case of putting type information into attributes is
discussed in [1], which is compatible with the requirement to persist
attributes.

> I believe the spec is silent about other attributes.

The spec is silent about what the value of a property actually is. So this
needs to be resolved (issues list [2], issue "PROP_ROUNDTRIP").

> Now that objections have been raised, who feels strongly for one side or

I feel strongly for keeping it this way, although I'd prefer wording that
uses the more precise terminology from the XML Infoset
recommendation.PROP_ROUNDTRIP. In particular I'd prefer to delay any change
until the issues above have been dicussed.

Julian

[1]
<http://greenbytes.de/tech/webdav/draft-reschke-webdav-property-datatypes-la
test.html>
[2] <http://www.webdav.org/wg/rfcdev/issues.htm>

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