Here we go... ;) Pádraic Brady
http://blog.astrumfutura.com http://www.survivethedeepend.com OpenID Europe Foundation Irish Representative ________________________________ From: Matthew Terenzio <[email protected]> To: [email protected] Sent: Wed, October 21, 2009 11:28:32 PM Subject: [pubsubhubbub] Re: Review of Core 0.2 draft - style issues What is an update? On Wed, Oct 21, 2009 at 6:19 PM, Bob Wyman <[email protected]> wrote: > Please.... Please.... Don't anyone restart the "What is an update?" > discussion... Too many lives have been wasted on that one already. > > bob wyman > > On Wed, Oct 21, 2009 at 6:11 PM, Tim Bray <[email protected]> wrote: >> >> >> 3. High-level Protocol Flow, last bullet point. "The hub caches >> >> minimal metadata..." I read this a few times and it seems to be >> >> describing one particular implementation strategy. If so, why not say >> >> so? The current language makes it look like this is maybe a normative >> >> part of what you have to do to implement PuSH, which I'm pretty sure >> >> it isn't. >> > >> > I think this is intended to be normative. A stateless hub can't >> > function properly (doing feed diffs). The language here was chosen >> > specifically to imply stateful handling of content without dictating >> > the specific implementation. >> >> In fact, what you're specifying is that the hub MUST be able to detect >> a delta so it can inform subscribers. Normative text should specify >> policy not mechanism. >> >> This touches on a nasty subject that you probably don't want to go >> near. If I were implementing, I think it might be perfectly OK to >> stash just atom:feed/atom:updated and //atom:entry/atom:updated. >> >> I am quite sure there are others who would disagree & insist on >> stashing enough to detect differences in the white space between >> attribute values. Don't laugh, I speak from bitter experience. If >> there's one thing we learned in the process of building 4287, it is >> hopeless to expect consensus on what constitutes an "update". I have >> a thousand emails to show you if you disagree. >> >> So I think it's probably inappropriate to specify "minimal" metadata. >> Just say "The hub stores sufficient state information about each topic >> to detect changes so that it can notify subscribers." -T > >
