Fedora 16, gnome-shell and rvm

I recently upgraded to Fedora 16.  There's lots to like.  There are some things that are annoying.

I found a couple of new oddities this evening after installing rvm.

First, rvm requires gcc, and gcc has to be installed.  I sort of assumed that gcc would have already been around.  Anyway,

sudo yum install gcc

did the trick. Second, after

• installing rvm
• logging out
• logging back in
• installing Ruby 1.9.2
• installing the latest JRuby
• logging out
• logging back in

I ran :

rvm use jruby

I got :

RVM is not a function, selecting rubies with 'rvm use ...' will not work.

Huh?

There is of course an entry on the rvm site.  It's some gnome-terminal weirdness.  I was launching the terminal with Alt + F2.

RVM, jRuby, ActiveRecord::ConnectionNotEstablished, and PostgreSQL

I generated a new Rails 3 app with a PostgreSQL backend.  I was using the latest jRuby.

I started the server and got :

ActiveRecord::ConnectionNotEstablished

That was annoying.
I connected to the database from the command line and from another tool.
I ran rails console and got the following :

ArgumentError: syntax error on line 42, col 0: `'
                    load at org/yecht/ruby/YParser.java:152
                    load at /home/[USER NAME]/.rvm/rubies/jruby-1.6.5/lib/ruby/1.8/yaml.rb:134
  database_configuration at /home/[USER NAME]/.rvm/gems/jruby-1.6.5/gems/railties-3.2.1/lib/rails/application/configuration.rb:115

Taking a look at yaml.rb line 134 clued me in that I was using the wrong jRuby compatibility.

RVM to the rescue.  RVM is just pure goodness.  It really makes switching rubies a breeze.

The executive summary is that RVM makes it easy to run multiple versions of Ruby and/or Ruby gems.  To use jRuby :

rvm use jRuby

It even makes it easy to set jRuby's version compatibility.  RVM  allows you to specify hooks to run after its' methods.

jRuby 1.6.x has 1.8 and 1.9 Ruby compatibility.  To use 1.9 just add an "after_use" hook (this is detailed on the RVM site).

Gradle

A few years ago I read The Pragmatic Programmer.  The Pragmatic Programmer may not be the GoF book, but it's almost as valuable.

Andy Hunt and Dave Thomas recommend learning a new language every year. I started with Groovy.

Being a Java developer I thought Groovy would give me the most bang-for-the-buck. After all Groovy is part of the Java spec so there is no excuse not to learn it.

I think Groovy delivered. I used to think that Groovy was worth learning for XML parsing/writing alone. XMLSlurper and MarkupBuilder are by far the best things I've used for dealing with XML.

Gradle changed my mind. Gradle is a fantastic build tool. Maven solves some problems, but it is a whole set of problems itself. Gradle can run Ant tasks so you keep Ant's functionality. 

As for the one language per year thing I picked up Python next and got a Django app into production. I'm on Ruby now, but I'm behind schedule. I'll get to Scala soon...

No bundle plugin resource available to handle deployment for bundle type

The first time I tried deploying a bundle with a fresh server and JBoss Operations Network agent I got the following error :

java.lang.Exception:No bundle plugin resource available to handle deployment for bundle type [BundleType[id=10001,name=Ant Bundle]]. Ensure the bundle plugin is deployed and its resource is imported into inventory.

I restarted the agent and everything was fine.

If I can reproduce this its time to login to Bugzilla.  I thought I'd post here first in case anyone Googles the Exception though.

Happy coding

PAE kernel

I use virtual machines a lot and really need more memory (more than 3.7GiB.)

Unfortunately I'm still running 32 bit Fedora 14.  I tried the 64 bit version, but had some problems with Firefox and Eclipse.



I've put off upgrading because of Gnome 3.  I tried out the Live Disc for 15.  It didn't convince me.

Since then I've heard enough good things about Gnome Shell that I'm willing to bite the bullet.  But just to play it safe I've been waiting until I have a few days with no meetings.  So meanwhile...

I added memory and installed the PAE kernel.

sudo yum install kernel-PAE

Pretty simple and my machine immediately recognized the extra memory.

SELinux and WebEx playback

While trying to watch a WebEx recording I got only sound and an SELinux alert.

I had to set SELinux to "Permissive" :

# setenforce Permissive 

A small price to pay.

The WebEx, btw, was Kris Verlaen's presentation on jBPM5.

JBUG ATL or Atlanta JBoss Users Group

The Atlanta JBug kicks off December 14.

The meeting will be held at :
Shadow-Soft
8200 Roberts Drive, Suite 201, Atlanta, GA