net-ssh using sudo pty sessions and regular session

net-ssh-sudo.rb

#!/usr/bin/ruby
require 'rubygems'
require 'net/ssh'

user = "vagrant"
pass = "vagrant"
host = "192.168.1.120"

###
# Commands without elevated privileges
###
commands = %Q{
hostname
uptime
id
}

###
# Commands that are ran with elevated privileges
###
sudo_com = %Q{
echo "#{pass}" | sudo -S id
[ -f /usr/bin/apt ] && sudo apt-get -y install apache2 || yum groupinstall -y "Web Server"
echo "UPTIME"
uptime
echo "BUILD:"
getconf LONG_BIT
echo "HOSTNAME"
hostname
sudo dmidecode -t bios
uptime
hostname
}

###
# All of the magic is done here for non-elevated priv commands
# This all that is needed if logging on as root is allowed
###
Net::SSH.start( host, user, :password => pass, :paranoid => false ){|ssh|
  begin
    ###########################################################
    # Executing non-priv commands
    ###########################################################
    puts "========================\nDoing non-priv commands\n========================\n".upcase
    result = ssh.exec!(commands)

    ###########################################################
    # Executing priv commands with sudo
    ###########################################################
    ssh.open_channel{ |channel|
      channel.request_pty{|ch, success| # This is needed to start a sudo session on remote system
        if success
          puts "========================\npty session successfully obtained\n========================".upcase
          puts "========================\nExecuting priv commands\n========================".upcase
          ch.exec(sudo_com){|i, data|
            i.on_data{ |step, info|
              print info.upcase
            }
          }
        else
          puts "could not obtain pty".upcase
        end
      }
    }
    puts result.upcase
  rescue Net::SSH::HostKeyMismatch => e
    puts "remembering new key: #{e.fingerprint}"
    e.remember_host!
    retry
  end
}