error stanzas are not handled correctly

[mhellwig]

I am using XEP-0198 with a prosody server and yaxim as client (yaxim in the nightly version that supports it). For the case where the client reconnects before the session timeout runs out, everything works great. For the case where the session timeout happens, there is the following problem.

According to XEP-0198, "A server SHOULD treat unacknowledged stanzas in the same way that it would treat a stanza sent to an unavailable resource, by either returning an error to the sender or committing the stanza to offline storage." I.e. it is legal for the server to return an error. The implementation of XEP-0198 for prosody does this as described here http://code.google.com/p/prosody-modules/wiki/mod_smacks namely "If the client fails to reconnect before the timeout then it is marked offline as normal, and any stanzas in the queue are returned to the sender as a "recipient-unavailable" error."

From what I understand, this error is a stanza that has the same message ID as the original message it relates to, no content and is of 'type="error"'.

If yaxim as a sender receives such an error (because the intended recipient of the message lost network connectivity long enough to trigger the timeout on the server) it SHOULD (imo) inform the sending user of this error. It doesn't. IMO this is a bug.

(to be fair, e.g. bitlbee and psi also have this bug)

[mhellwig]

as mentioned by flow on IRC, this is a more generic issue in that there can be other reasons why an error stanza could be generated, it's not limited to XEP-0198.

So probably the title should renamed "error stanzas aren't handled correctly"?

[ge0rg]

Ok, I have changed the error handling code in yaxim to update the delivery status of the original message, and to show the error message as a new message, both highlighted in red. Please test the APK.