Re: Hierarchical naming and external DAV members

   From: "Gerbert Orasche" <gorasche@hyperwave.com>

   We are currently developing WebDAV
   support for HWIS. In our system, names (used to generate the URL) are not
   restricted to be hierarchical, unlike in all filesystem based servers.

An HTTP URL is by definition hierarchical.  Just for interests sake,
how do you generate a (hierarchical) HTTP URL from a non-hierarchical name?

   The
   standard now talks of DAV controlled resources (internal members) and non
   DAV controlled resources (external members).

A member of a collection is by definition a resource whose URL has a
syntactic relationship with the URL of the collection, namely, that
the URL for the collection is a slash terminated proper prefix of the
URL for the member.  An "internal member" ("immediate member" would
probably have been a more intuitive term, but I digress :-) is a collection
member whose URL only adds one segment to the URL of the collection.

The term "external member" is not used or defined by WebDAV.
There is no concept of a "non DAV controlled member".

You could use the DAV:displayname property to store the non-hierarchical
name for the resource, and then DAV clients might display this in their
presentation layers (many/most just use the URL).

   Unfortunately most DAV clients
   treat both types of members the same and thus are construcing wrong URLs for
   our non hierarchical external members.

The standard does not define a "non hierarchical external member", 
so it's hard to see how DAV clients could be accused of constructing
wrong URL's for them (:-).

   So my questions: Why is the HREF attribute absolutely necessary but not used
   for the URL when accessing an object?

It is used when accessing a resource, but a server is not free to put what it
wants in there ... it must be a "legal" member name, i.e. the URL of the
parent extended by a single segment.

   Why is the MS implementation of WebDAV
   client (Web Folders) not distinguishing between the display name and the
   name? Does anybody have experiences with WebFolders, e.g. that they are
   using their own, out of the standard attributes?

Many/most DAV clients display the URL of a resource instead of the
DAV:displayname, because only the URL can be used to reliably lookup
the resource (many resources can have the same DAV:displayname).

Cheers,
Geoff

Received on Friday, 2 July 1999 11:27:27 UTC