Tag: pubsub

XMPP4R-Observable now on GemCutter

Posted by – 10/10/2009

Just a quick update: XMPP4R-Observable is now on GemCutter. That’s due to GitHub disabling gem building, and although everybody can get the source from GitHub as usual, those who want to quickly install it using Rubygems can do:

bash$ gem install xmpp4r-observable -s http://gemcutter.org

Happy Hacking.

Apresentando XMPP4R-Observable

Posted by – 08/09/2009

Há apenas alguns dias fiz uma apresentação no FISL10 sobre a utilização de XMPP PubSub com Ruby e sobre um fork de uma biblioteca popular à qual acrescentei os rudimentos do PubSub. Naquela mesma apresentação listei uma série de problemas que aquela abordagem tem e falei sobre um roadmap para o futuro…

Acontece que acabei me convencendo de que não posso utilizar o PubSub no lado XMPP da biblioteca e uma forma de periodical pooling no lado Ruby. Resolvi, então, substituir a biblioteca que havia forkado por uma versão Observable, preservando as coisas boas do XMPP4R-Simple. O resultado chamei de XMPP4R-Observable, e acabo de publicar no GitHub.

Uma boa parte do código está coberta por testes (e “roubei” alguns dos testes da própria XMPP4R-Simple)… pretendo cobrir o restante ao longo do tempo (contribuições são bem-vindas). Por hora, chamei esse primeiro release de versão 0.5.1 e acrescentei um .gemspec para gerar um .gem automaticamente… No entanto, o GitHub ainda não publicou o .gem… Quando publicar, para instalá-lo deve ser tão simples quanto:

bash# gem sources -a http://gems.github.com
bash# gem install spectra-xmpp4r-observable

Não deixem de reportar qualquer erro. Happy hacking.

Update 2009-09-13 10:29:00: Acabo de confirmar que o .gem foi publicado pelo GitHub.

Update 2009-10-10 20:21:00: O .gem do XMPP4R-Observable vai ser mantido no GemCutter, a partir de hoje.

PubSub with XMPP4R-Simple

Posted by – 18/03/2009

As I already told you, I am using XMPP4R-Simple in an internal project. For this, I’d have to add PubSub capabilities to it, and I did when I decided to get serious with git. Today I committed a version with integration of various patches by other forks I found on GitHub plus a lot of improvements on PubSub functions.

With this version it’s simple to use PubSub like this:

require 'xmpp4r-simple'
# Simple function just to parse an event
require 'time'
def parse_event(event)
  item = event.children[0]
  node = item.node
  time = nil; item.each_element("//published") { |e| time = Time.parse(e.text) }
  text = nil; item.each_element("//body") { |e| text = e.text }
  return { :item => item, :node => node, :time => time, :text => text }
# Create the clients
im1 = Jabber::Simple.new "im1@example.com", "password"
im2 = Jabber::Simple.new "im2@example.com", "password"
# im1 creates a node
# im2 subscribe to that node
# We'll start a simple thread to get the events coming from that node to im2
Thread.new { loop {
  sleep 1 while ! im2.received_events?
  im2.received_events { |event|
    h = parse_event(event)
    puts ">>> Got an event from node #{h[:node]} published at #{h[:time]} with text #{h[:text]}"
# Now im1 just publishes anything to that node.
im1.publish_atom_item("/some/node", "This is my node", "This is the content of my node")
# The thread should capture the event and run puts on the hash from parsing.

PubSub is great, isn’t it?

Alright! I surrender: Git rules!

Posted by – 05/02/2009

Everybody seems to be using git these days… I am not very found of “hypes”, as I told you before, but there’s been some time I’ve been evaluating git. I was happy with svk for quite a long time… Lately, though, I’ve been developing and extending a lot of ruby libraries, and all of them seem to be hosted at GitHub and using git… So, why not give it a serious try?

I chose a simple task on my TODO-list: to extend xmpp4r-simple to support XMPP PubSub, so I could use it in an internal project at my company. So I “cloned” its git repo and started developing. Not a really hard task, since all I had to do was use the underlying library (xmpp4r – not surprisingly also in GitHub) and mimic what Blaine’s done for the callbacks and it was ready (and working… although I still need to put more time on the test suite).

I am still exploring… It will take some time to migrate my stuff (and maybe a lot will remain in my company’s Subversion), but that’s what git-svn is for, isn’t it? Right now I am looking for ways to work with git-buildpackage and Debian git tools… Do you have some advice on that?