To: ietf-dav-versioning@w3.org Message-ID: <OF3CA0C14E.0EF4A683-ON85256958.00728F96@raleigh.ibm.com> From: "Jim Amsden/Raleigh/IBM" <jamsden@us.ibm.com> Date: Tue, 12 Sep 2000 16:55:00 -0400 Subject: Re: Naive question Geoff, I think there are some problems with what you describe below. Any operation on a version selector should be redirected to the target version including PROPFIND/PROPPATCH regardless if a Target-Selector header was specified or not. The Target-Selector header is only there to override the DAV:target of the version selector. We don't want different semantics depending on how you specified you version. Version selectors are special resources, not bindings (too bad, but they aren't), so we can define the semantics of PROPFIND/PROPPATCH on a version selector to return both its properties and the properties of its target version. There should be no overlap, so no properties will be hidden. I think this is consistent with the definition of target in the core versioning section. From: Tim_Ellison@uk.ibm.com How do you refer to a version selector rather than the version it selects? (i.e. to PROPFIND/PROPPATCH it's properties) A version selector has a URL which is different from the URL of any particular version. When you do a PROPFIND/PROPPATCH on a version selector URL, you operate on the properties of the version selector. When you do a PROPFIND/PROPPATCH on a version URL, you operate on the properties of the version. Note though that all the dead properties of a version selector correspond (i.e. have the same value) as those of the version that is that target of that version selector. Further note that if you use a Target-Selector header with a PROPFIND/PROPPATCH request, you operate on the properties of the selected version, and *not* on the properties of the version selector. From: "Jim Amsden/Raleigh/IBM" <jamsden@us.ibm.com> You can't. PROPFIND returns the properties of both. PROPFIND returns the properties of whatever resource you applied it to. In particular, the live properties of a version selector can be different from those of its target version. A while back, we modeled version selectors as a "redirector" that redirected methods to the version, but that was a good while ago, before we looked carefully at modeling versioned collections. Note that we can create version selectors with VERSION-CONTROL, but DELETE doesn't actually say you can delete them. You can use DELETE to delete a version selector. DELETE of a version is undefined. That is correct, but DELETE of a version selector is defined. DELETE on a version selector should just delete the version selector, but then we have a special case where the version selector is accessed as a resource itself. A version selector is always accessed as a resource itself. A Target-Selector header can be used to redirect a request from a version selector to the specified version, but without a Target-Selector header, a method applied to a version selector URL is applied to the version selector resource. Remember the BIND/DELETE/UNBIND arguments? Geoff? Yes, we used to need this kind of argument when we modeled version selectors as redirectors, but we don't need them any more, now that we don't model them that way anymore. Cheers, Geoff