[JDEV] Presence probe requests

[Richard Dobson]

> > A transport typically requires a user to login (either by doing a
> > registration or sending presence to the transport). After the login, it
> > sends available presence for the foreign network entities that the user
> > is subscribed to (assuming they're online).
>
> The problem is if my server stops, then any already logged in user
> still appears online to the transport.

Your server should be sending unavailables if it stops, and if it crashes
should probably do that on startup to clear everything up.

> Once my server starts again,
> and the user reconnects I need to know the state of all their
> contacts. Sending an online presence to the transport server does not
> cause their contact states to be resent (since they were already
> considered as online). So I thought probing their states would help. I
> also tried sending an unavailable, immediately followed by an online
> message to the transport in the hope it would resend all their contact
> states. This only served to confuse the transport with it not always
> paying attention to the order I send the requests in and the result
> being that the user ends up appearing offline to the transport. My
> current plan is to wait a few seconds between sending the unavailable
> and online status messages again, but that seems to be more
> complicated than it needs to be just to request the states of all
> contacts. Is there any other way to request the state of all contacts
> other than using individual probes for each contact?

No, only logging off and then back on.

Richard