>The core problem here is that presence is not necessarily reliable or >immediate. Does the notification ever show up anywhere
No, it never shows up. I suspect the browser gets it but my handler for XmlHttpRequest is gone by then, so the data is tossed. On Thu, Jan 28, 2010 at 3:52 PM, Liam <pub...@networkimprov.net> wrote: > 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 <pub...@networkimprov.net> 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 >> >> >
