RE: DELETE Semantics in Advanced Collections

Yes. That's it in a nutshell.

--Judy

> -----Original Message-----
> From: Yaron Goland [mailto:yarong@microsoft.com]
> Sent: Friday, May 21, 1999 2:46 PM
> To: 'Slein, Judith A'; 'WebDAV'
> Subject: RE: DELETE Semantics in Advanced Collections
> 
> 
> Before I comment on the appropriateness of this proposal I 
> would like to
> make sure that I understand its purpose. I suspect that the advanced
> collection group's motivation is that they are concerned that existing
> clients using existing commands will cause the "wrong" thing 
> to happen. 
> 
> That is, an advanced collection client creates an extensive system of
> bindings to a particular resource. What the advanced 
> collection client would
> like to see happen is that if some down level client shows up 
> and issues a
> DELETE only the particular binding they are trying to delete 
> will be removed
> rather than the actual resource, which would collapse their carefully
> crafted system of bindings to that resource.
> 
> 	Is that an accurate summary?
> 
> 				Yaron
> 
> 
> > -----Original Message-----
> > From: Slein, Judith A [mailto:JSlein@crt.xerox.com]
> > Sent: Thu, May 20, 1999 1:17 PM
> > To: 'WebDAV'
> > Subject: DELETE Semantics in Advanced Collections
> > 
> > 
> > The authors of the advanced collections spec would like to 
> get general
> > reactions to the DELETE semantics that appear in section 
> 4.2.8 of our
> > current spec.  I've extracted some relevant definitions and 
> > the text of
> > 4.2.8:
> > 
> > Binding
> >      An association between a single path segment and a resource.  
> >      Because a binding is a member of a collection, a 
> binding creates 
> >      one or more URL mappings to the resource.
> > 
> > Collection
> >      A resource that contains a set of bindings, termed member 
> >      bindings, which identify member resources.
> > 
> > Member Binding
> >      A binding that is a member of the set of bindings 
> contained by a 
> >      collection.
> > 
> > URL Mapping
> >      An association between an absolute URL or URI and a 
> resource. It 
> >      is possible for a resource to have zero, one, many, or even an 
> >      infinite number of URL mappings to URLs or URIs. Mapping 
> > a resource to 
> >      an "http" scheme URL makes it possible to submit HTTP protocol 
> >      requests to the resource using the URL.
> > 
> > 4.2.8 DELETE and Bindings
> > 
> > The DELETE method requests that the server remove the 
> binding between 
> > the resource identified by the Request-URI and the binding 
> name, the 
> > last path segment of the Request-URI (with trailing slash, if 
> > present). 
> > The binding MUST be removed from its parent collection, 
> identified by 
> > the Request-URI minus its trailing slash (if present) and 
> > final segment. 
> > If DELETE removes the last binding to a resource, the 
> server MAY also 
> > reclaim system resources associated with the resource.
> > 
> > Since DELETE as specified in [WebDAV] is not an atomic 
> > operation, it may 
> > happen that parts of the hierarchy under the request-URI cannot be 
> > deleted.  In this case, the response is as described in [WebDAV].
> > 
> > Section 8.6.1 of [WebDAV] states that during DELETE 
> > processing, a server 
> > "MUST remove any URI for the resource identified by the 
> > Request-URI from 
> > collections which contain it as a member."  Servers that support 
> > bindings SHOULD NOT follow this requirement.
> > 
> > -----------------
> > 
> > In addition, we are proposing to add to the specification an 
> > All-Bindings
> > header for use with DELETE.  This would request the server to 
> > remove all of
> > the bindings to the resource, and would allow the server (but 
> > not require
> > it) to reclaim system resources associated with the 
> resource once the
> > bindings were removed.
> > 
> > --Judy
> > 
> > Judith A. Slein
> > Xerox Corporation
> > jslein@crt.xerox.com
> > (716)422-5169
> > 800 Phillips Road 105/50C
> > Webster, NY 14580
> > 
> 

Received on Friday, 21 May 1999 15:10:01 UTC