Playing with Akka + Groovy + REST + Maven

07 Feb 2012

First things first, I consider myself a polyglot programmer reguarly running the spectrum from Java to Groovy to JRuby to Python.  Scala is certainly interesting from the outside looking in, but I haven’t had the time to jump in with both feet.

My latest forays into Akka came as a result of some investigation I was doing for a new platform at work.  Basically, I was looking for something to handle job/task execution across a number of different physical machines.

One option would have been to rig something up with Groovy, a simple daemon exposing a RESTful API (or fetched jobs from a message queue) that used GPars behind the scenes to manage concurrency on each individual machine.  Job state would be bubbling up to an overarching service that could manage scheduling across a few machines.

We’re already using Groovy/Java on a couple other newish projects and ideally the solution to this problem would also fit in that box.  Scala, as interesting a language as it is wouldn’t be fair to thrust on a team who’s language of choice has historically been Perl (but is moving towards the JVM).

And so I set forth to survey the landscape for Akka + Java/Groovy examples.  In particular, I was looking for something that combined Remote Actors + HTTP/REST, perferably being built in Maven (but I’d take some Gradle).  I found a few, the chat server ones looked relevant but a little bit dated.  I ended up putting something together myself and pushing it to github.

https://github.com/ajordens/akka-job-scheduler-example

It uses Akka 1.3 and has a server component (runnable via mvn jetty:run) that hosts remote actors and a simple REST resource.  There is also a client service that can be run on multiple machines, it polls the server for jobs, executes them and fires a response back.

The example is trivialized but it does tie a number of different pieces together.  One bit of initial grief I had was around trying to get akka-http running in Jetty 8.0.4.  It wouldn’t fly, and I ended up having to fall back to 7.4.0.

 

Enjoy.