- From: Slein, Judith A <JSlein@crt.xerox.com>
- Date: Tue, 18 Aug 1998 12:13:02 -0400
- To: "'WebDAV'" <w3c-dist-auth@w3.org>
- Cc: "Falkenhainer, Brian" <Brian_Falkenhainer@mc.xerox.com>, "Garnaat, Mitchell" <MGarnaat@crt.xerox.com>
Brian summarized his original issue to me very succinctly this morning: WebDAV equates semantic containment with syntactic containment in a URL path. It assumes that any semantic containment relationships will be reflected in the URL path. Document repositories typically do not make this assumption. In fact, repositories strongly prefer not to make this assumption. They don't want to use location as a means of referring to objects they control, since location can change; they want to use an identifier that is guaranteed not to break. What we need to assess is whether making the assumption that semantic containment is reflected in the syntax of the URL has caused any serious problems in WebDAV. Jim Whitehead pointed out that document repositories can still construct valid WebDAV URLs that separate semantic containment from the URL. They simply show a flat namespace to the world in the URL, and maintain the containment relationships separately. John Turner has also pointed out that the repository can map its flat namespace into one that embodies the semantic containment relationships in URLs. This practice presumably is offensive to repository designers who so carefully avoided it in developing their products. Do clients care whether the URL embodies semantic containment relationships or not? Presumably not when they are navigating downward, since they will use PROPFIND to do that. But if they want to navigate upward in the containment hierarchy, WebDAV provides no standard way to do so except by parsing the URL. I suspect this is an oversight in WebDAV that may have resulted from assuming containment relations would be visible in the URL syntax. Unless it can be remedied, it means that repository vendors MUST construct URLs that show the semantic containment relationships. -- Judy Judith A. Slein Xerox Corporation jslein@crt.xerox.com (716)422-5169 800 Phillips Road 105/50C Webster, NY 14580
Received on Tuesday, 18 August 1998 12:14:28 UTC