RE: Docushare and WebDAV model

I don't understand what you are asking WebDAV to do. WebDAV provides a
feature, the ability to create hierarchical spaces, you choose not to allow
access to that feature, such is your right. WebDAV's requirements on the
matter are mostly written in the form of "If a URL is hierarchical then it
MUST do the following." If you don't use hierarchical URLs then there is no
issue.

As for cycles and such, I would refer you to the excellent work done by Judy
Slein and Jim Davis in their requirements draft for advanced collection
functionality, it covers references
(http://www.ietf.org/internet-drafts/draft-ietf-webdav-collection-reqts-02.t
xt) and specifically addresses the issue of cycles as well as depth
operations on references in collections.

		Yaron

> -----Original Message-----
> From: John Turner [mailto:johnt@cgocable.net]
> Sent: Sunday, August 16, 1998 7:09 PM
> To: w3c-dist-auth@w3.org
> Subject: RE: Docushare and WebDAV model
> 
> 
> 
> To some extent I agree, it is a UI issue.  The point of my 
> two previous
> submissions is that while it is possible to represent the 
> document store as
> a flat space, it is not very useful to users with a generic 
> WebDAV client,
> because of the restrictions made on what kind of operations 
> they are allowed
> to do.  One of the points of WebDAV is that this kind of 
> interoperability is
> important.  We specifically do NOT want to have more than one 
> "model" of
> basic user interaction although clearly a client that 
> understands how to do
> more than the basics when talking to the "right" server is fine.
> 
> On the other hand it is not correct to say that this is not a protocol
> issue.  It is an issue of mapping from one model to another 
> and the choices
> made in the WebDAV protocol that make this mapping difficult 
> are exactly the
> point.
> 
> One significant problem with mapping the documents space into 
> a hierarchy is
> that, depending on the undelying system, cycles may be possible in the
> document's collections, leading to a possibly infinite hierarchy.  The
> protocol document does not address what to do with an 
> infinite space when
> asked to do a PROPFIND with depth="infinity".  Clearly it has 
> to return a
> finite result, but the choice of where to stop and what it 
> should return at
> the point of stopping are issues that should be agree upon.
> 
> At 01:16 PM 8/14/98 -0700, you wrote:
> >We need to be aware of the difference between UI and protocol. 
> >
> >The WebDAV protocol provides the various mechanisms you need 
> to perform the
> >actions you want. Creating a flat namespace, putting resources into
> >collections defined in that namespace, the use of error 
> codes to enforce the
> >flat namespace, etc. However WebDAV does not provide the UI 
> that would make
> >such a store sensible to a user.
> >
> >Thus users interacting with your store will need to use 
> programs which
> >present your stores in a reasonable way. Otherwise you will have to
> >synthesize a mapping of your flat store into a hierarchical 
> store. That is,
> >the actual store is flat but you create a phantom store that looks
> >hierarchical. It is not the protocol which is forcing you to 
> do this, it is
> >the types of clients people are writing to use the protocol.
> >
> >If the general user population decides your model is the 
> best one then
> >clients will interact with DAV stores using your model.
> >
> >However, to be clear, this is not a protocol issue. It is a UI issue.
> >
> >		Yaron
> >
> >> -----Original Message-----
> >> From: John Turner [mailto:johnt@cgocable.net]
> >> Sent: Thursday, August 13, 1998 9:05 AM
> >> To: w3c-dist-auth@w3.org
> >> Subject: RE: Docushare and WebDAV model
> >> 
> >> 
> >> At 05:59 PM 8/10/98 -0700, you wrote:
> >> >Would not references solve the problem? Your entire 
> >> namespace is flat and
> >> >your collections contain nothing but references.
> >> >	Yaron
> >> >
> >> 
> >> Yes, that could be done.  It would allow the documents and 
> >> collections to be
> >> presented.  Unfortunately edit operations would be something 
> >> of a problem.
> >> A generic WebDAV client would find it a difficult space to 
> >> work with.  The
> >> only place that documents can be created is in the collection 
> >> representing
> >> the flat set of documents.  The server would either have to 
> >> disallow PUTing
> >> (etc) of documents anywhere but in the proper directory, or 
> >> else magic would
> >> have to happen (accepting the PUT and then moving it and creating a
> >> reference, or some such).
> >> 
> >> John Turner
> >> johnt@cgocable.net
> >> 
> >
> >
> 
> John Turner
> johnt@cgocable.net
>

Received on Tuesday, 18 August 1998 01:29:47 UTC