Message-ID: <3906C56A7BD1F54593344C05BD1374B10D9EB7@SUS-MA1IT01> From: "Clemm, Geoff" <gclemm@rational.com> To: ietf-dav-versioning@w3.org Date: Thu, 28 Sep 2000 12:03:00 -0400 Subject: RE: Question about "opaque" collections Yes, an "opaque" collection can be versioned as a whole, by putting it under "baseline control" (as opposed to "version control"). So while "version control" of a collection tracks versions of just that collection (i.e. it's internal members), "baseline control" of a collection tracks versions of all members of the collection. You can then use "SET-TARGET" and "MERGE" to bring back or merge previous baselines of the collection into the current state of the collection. Cheers, Geoff -----Original Message----- From: Bill Bumgarner [mailto:bbum@codefab.com] Sent: Thursday, September 28, 2000 11:33 AM To: ietf-dav-versioning@w3.org Subject: Question about "opaque" collections [I have been meaning to ask this for a while and hope that this is a repeat of an issue already dealt with] In this less than ideal computing environments that we work with, there is the occasional need to revision control or configuration manage a collection of resources that cannot be inventoried. That is, there are applications that effectively use a directory [collection] as a single atomic document. The contents of said directory/document/collection changes with each save in a non-predictable fashion. As applications evolve, the documents they manage are becoming more and more complex. As a natural result, collection of resources acting as a single atomic document are becoming more and more common. It is interesting to note that Apple's OSX supports collections as documents as a first class and standard part of the desktop application development APIs. Revision control systems such as CVS-- ones that expect the inventory of a directory to remain predictable across revisions-- have great dififculty managing such resources. For cvs, a nasty hack was implemented a number of years ago that effectively tarballs the collection and stores it as a binary, non-mergeable, resource within the repository. Because the collection is effectively closed in that the contents are meaingless outside of the context of the collection, "opaque collection" seems to be a reasonable way of naming such a thing. Question: Can the versioning features of DAV transparently and effeciently store and control "opaque" collections? I.e. can a collection of resources be treated as if it were a single, versionable resource? b.bum