The Atom Working Group has sailed through our IETF last call on the data format with a fairly small number of comments, none of them raising particularly troubling issues. This leaves us with a teeny little set of issues to settle, of which only one is really material: can the same entry show up more than once in a feed? It’s trickier than you’d think, but I can see the individual fibers in the finish line.
In Atom, every entry is required to have a title (yes, it can be empty, but it’s gotta be there), a date-stamp, and a unique ID. Easy enough; although you would not believe the amount of work it took to get to that consensus. So when you subscribe to an Atom feed, is it OK if two of the entries have the same ID?
First, the spec said nothing. Then there was a proposal to allow duplicates, but it failed to gain consensus, so the spec currently says you Can’t Do That. Which is provoking howls of pain from people like PubSub who publish all kinds of synthetic feeds, both aggregates and things like their earthquake watcher, which is worth a visit; there are plausible-sounding reasons for these kinds of feeds to contain duplicates. There are lots of examples too.
So the Atom WG has three (I think) proposals on the table for how to address this. I wrote one of them, and think it’s the best alternative, but if they all fail I suspect PubSub and the like will find a way to work around the problem, albeit kludgey.
Mostly, I’m just writing this because it’s nice to be near that finish line. Then we’re onto the last lap for the Publishing Protocol.
