Inject Ganglia metrics into Graphite

#!/usr/bin/ruby
require "rexml/document"
require 'socket'

ganglia_hostname = 'localhost'
ganglia_port = 8649
graphite_host = "localhost"
graphite_port = "2003"

begin
  # Open up a socket to gmond
  file = TCPSocket.open(ganglia_hostname, ganglia_port)
  # Open up a socke to graphite
  graphite = TCPSocket.open(graphite_host, graphite_port)
  # We need current time stamp in UNIX time 
  now = Time.now.to_i
  # Parse the XML we got from gmond
  doc = REXML::Document.new file
  doc.elements.each("GANGLIA_XML/CLUSTER/HOST") { |element|
    # Set metric prefix to the host name. Graphite uses dots to separate subtrees
    # therefore we have to change dots in hostnames to _
    metric_prefix=element.attributes["NAME"].gsub(".", "_")
    element.elements.each("METRIC") { |metric|
      if metric.attributes["TYPE"] != "string"                     
        graphite.puts "#{metric_prefix}.#{metric.attributes["NAME"]} #{metric.attributes["VAL"]} #{now}\n"
      end
    }
  }
  graphite.close()
  file.close()
rescue
end