Tag Archives: pubsub

Notifixious – A notification platform

I’ve recently registered to Notifixious home page, a notification platform that integrates XMPP natively. Though the application is not looking as polished as one might hope it already provides interesting features.

Overall I think any work towards better notification system is the right idea. We need better ways to notify people or get notified about relevant piece of information. From a technology’s perspective transport protocols (well at the application’s level) already exist to perform the task of carrying the information, they are namely HTTP and XMPP. However there is still quite a large gap to fill about what to carry exactly. Notifixious doesn’t solve that gap per se but offers at least a good base for playing around with some floating ideas. For instance I’ve introduced today the Notifixious’s crowd to LLUP which has been initiated and carried on for a few years now to answer that specific problem. Perhaps it’ll make it way through.

Update: The guys at Notifixious just posted a message about how PubSub is heavily used by their service.

jlib preview – PyQt4 library for XMPP

I’ve been recently working on a library called jlib that providing PyQt4 objects and widgets that can be integrated to a PyQt4 application. In other words jlib is not a new Jabber client but a toolbox to enjoy the benefit of XMPP. The XMPP work is performed by headstock, jlib only glues headstock to PyQt4 through the use of signals/slots.
jlib is not ready yet but here is a preview of a few widgets I’ve already started working on. Ultimately my main interests is in creating a decent toolbox of widgets centered towards XMPP PubSub.

XMPP, AtomPub, headstock, amplee and the BBC

Matthew Wood, from the BBC Radio Labs, posted a few days ago an exciting note regarding fun he was having with XMPP and services such as last.fm to inform user, via XMPP messages, of BBC radios broadcasting music they might like based on thier last.fm profile. I thought this was fantastic but I was even more excited when I read another note where he explained that he was using PubSub as a mean to carry and distribute metadata about BBC shows using Atom entries as the metadata format.
This evening I spent three hours expanding on the simple chat example coming with headstock to talk with the PubSub service. Then I integrated amplee as a way to offer an AtomPub interface at the same time. This means that when the demo starts both a XMPP client, connecting to Matt’s service, and an AtomPub server, using amplee and served by CherryPy, are started. The XMPP client asks the server about PubSub nodes. For each node representing BBC channels I create an atompub collection within its own workspace. Simultaneously I subscribe to those nodes. I then ask the XMPP server for items belonging to those nodes and for each item, representing metadata about a show for instance, I create an atom entry that I store within the AtomPub store.
This means one can then simply subscribe with a feed reader to a given collection and/or a XMPP PubSub node. All of this happening on the fly starting from an empty AtomPub service document.
Eventually I will add support so that when an Atom entry is POSTed to a AtomPub collection, the according PubSub stanza is pushed towards the service (I doubt Matt’s service accepts it though) allowing for microblogging support.
The source code of the example can be found here. If you want to understand how it works you might want to read this quick word I wrote about Kamaelia first which is at the core of headstock.

AtomPub and XMPP

There has been quite a lot of discussions around the use of XMPP in a web context and how to blend HTTP and XMPP protocols for a better social network experience.

I’ve been working on implementing XMPP for a while now on my spare time and even though it’s been a much slower effort I would have liked, I’ve been able to have a fantastic fun with it. Most recently I’ve started integrating XMPP PubSub along with AtomPub using my AtomPub implementation, amplee.
The idea is to use amplee as an AtomPub library from within XMPP PubSub handlers. For instance I map AtomPub collections to PubSub nodes . When an atom entry is published to a node and that the client receives an acknowledgment of that publication, the handler uses amplee to store the entry in the AtomPub collection as well, respecting of course the RFC specification. Similarly if an item is deleted, the handler uses amplee to remove the entry from the collection. This works both ways, we can also run an AtomPub web service which issues the right XMPP stanzas according to the operation carried. So a POST on a collection would publish the atom entry to the XMPP server. The web service would obviously expose the Atom feed of the collection.
This is just a stub, but the idea here is to associate both protocols so that they cooperate to expand the audience of your network. It’d be easy to consider allowing people commenting to a blog entry using their XMPP client. You blog entry would for instance advert the XMPP service and node name where to publish items. The user could then subscribe to than node and publish items.
That’s one reason why I had written amplee as an AtomPub library that could work outside of the HTTP protocol. RFC 5023 defines the protocol using HTTP but the root idea behind it works well in the context of XMPP and maybe AtomPub is the protocol that will rule them all.

XMPP, a ground for social technologies

I’ve been a long fan of the XMPP protocol and I’ve started implementing it using the fantastic Kamaelia. With all the GSoC discussion around it appeared that lots of people were more and more interested in seeing XMPP becoming the natural partner of HTTP in the maze that the Internet has quickly become. Consequently Peter Saint-André created today the Social mailing-list to all people interested in discussing how XMPP could be used in what is that social web of yours.

I’m totally biased but I think there is more to XMPP than IM, the protocol and its suite of extensions provide great power applicable to RIA, whether they reside inside our outside the browser. For instance, I do believe that rather than using Comet one ought to use XMPP to push notifications to the client. In such a case one might consider the client as a node in a cloud of lazily interconnected nodes and then start thinking of the browser as more than a HTML rendering engine and without the resort to abuse HTTP for things it was never meant to support.

I wish browser vendors could start implementing XMPP within the browser as that would provide a fantastic incentive for more applications based on the power of XMPP.