On Thu, Oct 8, 2009 at 10:26 AM, Ravi Pinjala <[email protected]> wrote: > > Kalv wrote: >> Hey all, >> >> First off love the protocol! >> >> I'm working with twitterfeed in London, to implement pubsubhubbub as >> one of the ways to get updates happening in realtime (well almost). >> >> In development we have implemented subscribing the topic with the >> relevant hub and for some we are getting notifications coming through. >> But i'm having some issues and would like to voice them and see if >> anyone has any advice: >> >> - We keep on getting multiple notifications from the >> pubsubhubbub.appspot.com hub, comparing the md5 of the notification >> they do seem to be the same, for now we do a duplicate check before >> processing any further. Is this normal behaviour? We do get normal >> duplicates, that are different, which are probably updates to the >> article. >> >> - I thought that blogspot had implemented Pubsubhubbub (http:// >> buzz.blogger.com/2009/08/blogger-joins-hubbub.html), but by creating a >> test blog I didn't see any hub declaration in an atom/rss feed, anyone >> know why this is so? Are they doing something different or just not >> implemented fully? >> >> - I'm finding it hard to debug subscriptions with TypePad, we set up a >> blog there and subscribed, is there a way to confirm that the >> subscription was successful? The hub sends the challenge as a http get >> to the callback and we send that back, but we don't get new post >> notifications - maybe this of topic here and could be a problem on >> their end. >> >> Cheers! >> Kalv. >> > I'm also seeing a lot of duplicate updates on my personal aggregator. > I've been watching this for a few days now, and there's no pattern that > I can discern in the entries that are getting pushed - it's usually 1-4 > recent (but not necessarily the most recent) entries in the feed. My > aggregator basically drops the update in a queue for further processing > and then returns, so unless there's something seriously wrong with my > internet connection, latency is well under a second. It does seem like > only certain feeds get duplicated updates, so it could be a bug that > only shows up under certain conditions. > > I can provide more details about my aggregator, and which entries > specifically are being duplicated, if necessary.
That'd be great. I'd also like to know what the feeds your subscribed to are and if you are totally sure you're seeing duplicate delivery. In many cases, the same item can be delivered multiple times even though only small changes have occurred (e.g., a timestamp, a link relation query-string parameter). Hubs will redeliver these entries anyways. Perhaps we should suggest a better heuristic for determining differences, though.
