Script to update jenkins to the latest version

hudson.xml

hudson_home: /home/cruisecontrol/apache-tomcat-6.0.16/webapps/hudson
hudson_ftp: ftp.osuosl.org
hudson_ftp_base_dir: pub/jenkins/war/

jenkins_update.sh

#!/usr/bin/env ruby

require 'fileutils'
require 'net/ftp'
require 'yaml'

if __FILE__ == $0
  @@config = YAML::load( File.open( 'hudson.yml' ) )
  hudson_home = @@config['hudson_home']
  hudson_ftp = @@config['hudson_ftp']
  hudson_ftp_base_dir = @@config['hudson_ftp_base_dir']

  def get_latest_hudson_war(hudson_ftp, hudson_ftp_base_dir)
    puts "hudson_ftp:          \"#{hudson_ftp}\""
    puts "hudson_ftp_base_dir: \"#{hudson_ftp_base_dir}\""
    puts "@@config['hudson_home']:  \"#{@@config['hudson_home']}\""
    Net::FTP.open(hudson_ftp) do |ftp|
      ftp.login
      puts ftp.list("#{hudson_ftp_base_dir}")
      latest_version_dir = ftp.list("#{hudson_ftp_base_dir}")[-2].split.last
      puts "directory di prelievo FTP: \"#{latest_version_dir}\""
      # I file sono ordinati in modo decrescente: l'ultimo è l'ultima versione
      files = ftp.chdir("#{hudson_ftp_base_dir}/#{latest_version_dir}")
      ftp.getbinaryfile('jenkins.war', "#{@@config['hudson_home']}/jenkins.war", 1024)
    end
  end

  def restart_hudson
    system("$HOME/restart_hudson.sh")
  end

  def unzip(filename)
    command = "unzip #{filename} -d #{@@config['hudson_home']}"
    success = system(command)
    success && $?.exitstatus == 0
  end

  if File.exist?(hudson_home)
    FileUtils.mkdir "#{hudson_home}/../XML" unless File.exist?("#{hudson_home}/../XML")
    x_l_files = Dir.glob("#{hudson_home}/*.x*l");
    FileUtils.cp x_l_files, "#{hudson_home}/../XML/" unless x_l_files.empty?
    FileUtils.rm_r Dir.glob("#{hudson_home}/*")
    get_latest_hudson_war(hudson_ftp, hudson_ftp_base_dir)
    unzip("#{hudson_home}/jenkins.war")
    all_from_XML_dir = Dir.glob("#{hudson_home}/../XML/*")
    FileUtils.cp_r(all_from_XML_dir, "#{hudson_home}/") unless all_from_XML_dir.empty?
    FileUtils.rm_r(Dir.glob("#{hudson_home}/jenkins.war"))
    restart_hudson
  else
    puts "ERRORE - Il percorso \"#{hudson_home}\" non sembra essere valido..."
  end

end

hi, my jenkins server is standlone and i want to upgrade the version to latest jenkins version.. could you please help on this.