Here comes another short update on my Google Summer of Code project.

Stanza acknowledgement is finally done, including representation in the GUI. You can see a short demonstration of the feature in the video below where I'm chatting with Matthew Wild, one of Prosody's main developers. He developed a module for Prosody that implements parts of Stream Management. This made my client side implementation much more easier to test.

The idea is simple: the status icon in the top left corner is replaced with a throbber animation, known to users from recent OSes and browsers, as long as there are messages that haven't been acked by the server.
Psi will at least request an ack after half a minute. However only if there's something to acknowledge for the server.

Here another short update.

Stanza acknowledgement from client to server is working now and chat dialogs get notified when a message sent by them has been acked by the server. The only thing left here is the visual representation in chat dialogs of unacked and acked messages.

After that is done I'll try to add support for session resumption and hopefully get it done till mid-term evaluation next week. Most of this stuff doesn't sound hard to implement however there is currently only one server implementation of XEP-0198 and that one only supports stanza acknowledgement, so it's a bit hard to test my client side implementation of it. XEP-0198 resulted out of long discussions in the XSF on how to improve reliability and the overall experience of chatting over XMPP. It's important that this extension is implemented so we can test in real life whether these changes help or not.

Here the short but little late update on my GSoC project status.

Acking requests coming from the server is basically implemented in Iris. Psi as a client can tell Iris that the last received stanza has been handled and Iris will take care of the rest.

Next on the list: Sending own acking requests to the server so we know the stanzas Psi's send have successfully been handled by the server.