Any comments on the issue of reliable delivery to offline subscribers? I seem to have this issue with ejabberd. Having configured pubsub#notification_type = normal (which queues items to offline subscribers), if I disconnect a subscriber (by closing a browser tab running strophe) and immediately publish an item, it doesn't always show up on reconnect, presumably because it is "delivered" before ejabberd knows the user is offline. If I wait a bit before publishing, the item does show up.
On Thu, Jan 28, 2010 at 2:17 AM, Liam <[email protected]> wrote: > Perhaps I'm missing something here... > > That presence-based delivery is an optional service feature implies that > items published are normally queued to node subscribers when they are > offline, and later delivered when they sign on. However I can't find this > explicitly stated in the spec. > > Also, the impact of persist_items on delivery to offline subscribers is not > discussed. Is a non-persisting node inherently presence-based delivery? > (Intuitively, I'd say not.) > > That on_sub_and_presence is an option for send_last_published_item could > imply that items published when a subscriber is offline need not be queued > for later delivery, which seems very strange. > > Also, I see no method for reliable delivery of items to offline > subscribers... IQ notifications seem to address this only for online > subscribers. This seems like a significant omission. > > I discovered this when I configured a node on ejabberd as follows, > expecting it to queue items if the subscriber is offline, as for normal > messages (which it doesn't): > > <field var='pubsub#notify_retract'><value>0</value></field> > <field var='pubsub#persist_items'><value>0</value></field> > <field var='pubsub#publish_model'><value>open</value></field> > <field var='pubsub#access_model'><value>whitelist</value></field> > <field var='pubsub#send_last_published_item'><value>never</value></field> > > Thanks, > > Liam > >
