This document discusses building an XMPP client in Pharo. It explains that an XMPP server is needed, such as OpenFire, and a C library binding like Libstrophe. It describes mapping callbacks between the C library and Pharo code to implement XMPP extensions. The goal is to create a basic one-to-one chat and multi-user chat client with a GUI, leveraging Pharo's capabilities for debugging and testing.

1. XmppTalk
Philippe Back
@philippeback

2. What is XMPP?
eXtensible Messenging and Presence Protocol

3. Uses of Xmpp

4. So, I wanted an XMPP client in Pharo for the Slack
Since them we moved to Discord qnd there is no XMPP there.
Anyway...

5. One needs a server
http://files.pharo.org/media/logo/logo-flat.png

6. Unpack and run OpenFire (Needs some Java)

7. One needs a non Pharo client

8. One does not want to recode the low level

9. Buiild 32 bit library for Pharo 32-bit
Use a continer (LXC)
Can do ith Docker as well. No need for docker with LXC.

10. One needs to bind to Pharo: UnifiedFF
UFFI Binding for Libstrophe

11. Interesting...
Typedefs
Constants
Callbacks

12. One needs a Pharo based client: XmppClient

13. One has to map callbacks

14. In order to implement XEPs

15. One has to see what is going on
Modeled after ZnLogEvent thing but will move to Beacon.

16. Raw stuff can also be logged !console) and one can
thus see the data stream

17. It is annoying to use test cases for interactive
exploration
Using RunCase approach

18. One needs a GUI, one day
Using Spec
Leveraging the announcements
Target is have a one to one chat and a MUC (Multi User Chat)

19. Conclusion
Pharo proved to be suitable for this
Very easy to implement callbacks
Promising for new XEPs
Stable
Easy to debug

20. Horizons
Have a couple XMPP servers in the cloud
Communicate right form the IDE