Ruby Gmetric example that counts dir listings and sends them to a ganglia cluster

Gmetric_count_dir_listings

#Simple ganglia gmetric plugin using the gmetric gem.
#Counts entries in a dir and reports them to the ganglia cluster using 
#the gmetric ruby gem
require 'rubygems'
require 'gmetric'

#Tmax indicates freshness, if TN(seconds since metric was updated) exceeds tmax then ganglia will expect a new value
#Dmax indicates how long an old metric should be retained 
#decsripitions taken from http://monami.sourceforge.net/tutorial/ar01s06.html
tmax = 60
dmax = 300
#first argument is a host gmond host in the cluster
#second argument is the port 
gmondhost = ARGV[0]
gmondport  = ARGV[1]
dir = '/home/ken/'
graph_name = "Directory Listing Count in #{dir}"
units = "Files/Directories"
file_count =  Dir.entries(dir).count

Ganglia::GMetric.send(gmondhost, gmondport, {
    :name => graph_name,
    :units => units,
    :type => 'uint8',
    :value => file_count,
    :tmax => 60,
    :dmax => 300
  })