Hi All- For what it is worth, there was a fairly in-depth conversation about tombstones back in Dec 2007. James Snell (and others) put forth strong arguments against it just being another atom:entry (I was among those, at the time, advocating for atom:entry, but I have come around to the lighter option mainly for practical (not aesthetic) reasons).
The thread begins here, and may be worth perusing (follow links to follow-ups): http://www.imc.org/atom-syntax/mail-archive/msg20050.html --Peter On Mon, May 24, 2010 at 2:08 PM, Bob Wyman <[email protected]> wrote: > Erik, > I don't think we would have to go as far as changing the semantics of any > standard atom elements. Rather, what I'm suggesting is that "delete" is > really just a bit of an extension to what the existing replace means. In > other words, if you understand the "delete" flag, however, it is encoded, > you would do a delete, if not, then you would simply do a replace as per the > existing spec. This would be properly backwards-compatible. > I would, of course, regret breaking any early-adopter code. However, I > suggest that there is a much larger population of long-ago-adopters who > wrote Atom code potentially years ago and would, if deleted-entry became > accepted, have to consider rewriting or at least modifying their code. One > of the risks of being an early adopter is that things may change, however, > people who wrote code to the published spec should be granted the right to > expect that things will be more stable. > The only downside I can see in extending the existing entry is that the > resulting tombstones would be a bit less bit-efficient than desirable. (i.e. > they would, in most cases, probably end up having empty required elements -- > such as atom:title.) > bob wyman > On Mon, May 24, 2010 at 2:28 PM, Erik Wilde <[email protected]> wrote: >> >> hello. >> >> Bob Wyman wrote: >>> >>> The Tombstone draft is coming along nicely, however, I can't help >>> wondering... Since it appears that a deleted-entry is so much like a normal >>> entry, why isn't it just an extended atom:entry with some additional element >>> or attribute flagging it as deleted? >> >> i think this is a great approach of looking at what "deletion" means, in a >> way it's just another "update". however, there probably are two major >> problems with this approach: >> >> - it is not backwards-compatible with prior versions of the draft, and it >> seems that the draft already has seen some adoption. if the goal is to not >> break these early implementations, then moving from deleted-entry to entry >> is not an option, i am afraid. >> >> - atom disallows extensions to change the semantics of any standard atom >> elements. whether additional metadata changing the semantics of an "updated" >> entry to a "deleted" entry is such a change in semantics is a question of >> perspective. one could say that "deleted" is different from "updated", or >> one could say that it's just a special case. >> http://tools.ietf.org/html/rfc4287#section-4.2.15 just says that 'The >> "atom:updated" element is a Date construct indicating the most recent >> instant in time when an entry or feed was modified in a way the publisher >> considers significant', which i think could be seen as covering the case of >> deletion of an entry as well. >> >> personally, i think that having an entry/@deleted would be quite a bit >> more elegant and consistent than having a deleted-entry (there is no >> updated-entry, after all...), but that still does not solve the problem of >> breaking early adopters' code. but for me, the most important thing is to >> have something in feeds that covers the CRUD's D, so i am very glad to see >> the tombstone draft moving along again, whatever it will end up defining. >> >> cheers, >> >> erik wilde tel:+1-510-6432253 - fax:+1-510-6425814 >> [email protected] - http://dret.net/netdret >> UC Berkeley - School of Information (ISchool) >> > >
