I usually use Ubuntu 10.04 as my server platform. Now that I'm switching to ruby 1.9.2 in production, the utter crapness of the built-in Ubuntu packages has become unsupportable (ruby 1.9.1 doesn't work with Bundler, for example).

So, I wanted a way to install ruby 1.9.2 using Puppet. This is what I came up with. The files fit together like this;

In my site.pp file, I've got this;

import "ruby192"
include ruby

The init.pp file just contains this;

import "*"

The real fun is in the ruby.pp file;

class ruby {

  exec { "apt-update":
    command => "/usr/bin/apt-get update"
  }

  # pre-requisites
  package { [
      "gcc",
      "g++",
      "build-essential",
      "libssl-dev",
      "libreadline5-dev",
      "zlib1g-dev",
      "linux-headers-generic"
    ]:
    ensure => "installed",
    require => Exec["apt-update"]
  }

  # put the build script in /root
  file { "/root/build-ruby.sh":
    ensure => "present",
    source => "puppet:///modules/ruby192/build-ruby.sh",
    mode => 755
  }

  # run the build script
  exec { "build-ruby192":
    command => "/root/build-ruby.sh",
    cwd => "/root",
    timeout => 0,
    creates => "/usr/bin/ruby",
    require => File["/root/build-ruby.sh"]
  }

  # update rubygems
  exec { "update-rubygems":
    command => "/usr/bin/gem update --system",
    unless  => "/usr/bin/gem -v |/bin/grep ^1.8",
    require => Exec["build-ruby192"]
  }

}

As you can see, it updates the apt cache, installs some pre-requisites and then runs a script to build ruby 1.9.2 from source. The "timeout => 0" line is important. Without it, puppet will not allow long enough for the build script to run completely. Here's the build script;

#!/bin/bash

RUBY_VERSION='ruby-1.9.2-p290'

wget "http://ftp.ruby-lang.org/pub/ruby/1.9/${RUBY_VERSION}.tar.gz"
tar xzf ${RUBY_VERSION}.tar.gz
cd ${RUBY_VERSION}
./configure --prefix=/usr && make && make install

That will install ruby 1.9.2 and rubygems, so all that remains for the ruby.pp module is to update rubygems to the latest version.