es-node-metrics.rb

#!/usr/bin/env ruby
#
# ElasticSearch Metrics Plugin
# ===
#
# This plugin uses the ES API to collect metrics, producing a JSON
# document which is outputted to STDOUT. An exit status of 0 indicates
# the plugin has successfully collected and produced.
#
# Copyright 2011 Sonian, Inc <chefs@sonian.net>
#
# Released under the same terms as Sensu (the MIT license); see LICENSE
# for details.

require 'rubygems' if RUBY_VERSION < '1.9.0'
require 'sensu-plugin/metric/cli'
require 'rest-client'
require 'json'

class ESMetrics < Sensu::Plugin::Metric::CLI::Graphite

  option :scheme,
    :description => "Metric naming scheme, text to prepend to queue_name.metric",
    :short => "-s SCHEME",
    :long => "--scheme SCHEME",
    :default => "#{Socket.gethostname}.elasticsearch"

  option :host,
    :description => "Elasticsearch server host.",
    :short => "-h HOST",
    :long => "--host HOST",
    :default => "localhost"

  option :port,
    :description => 'Elasticsearch port',
    :short => '-p PORT',
    :long => '--port PORT',
    :proc => proc {|a| a.to_i },
    :default => 9200

  def run
    ln = RestClient::Resource.new "http://#{config[:host]}:#{config[:port]}/_cluster/nodes/_local", :timeout => 30
    stats = RestClient::Resource.new "http://#{config[:host]}:#{config[:port]}/_cluster/nodes/_local/stats", :timeout => 30
    ln = JSON.parse(ln.get)
    stats = JSON.parse(stats.get)
    timestamp = Time.now.to_i
    node = stats['nodes'].values.first
    node['jvm']['mem']['heap_max_in_bytes'] = ln['nodes'].values.first['jvm']['mem']['heap_max_in_bytes']
    metrics = {}
    metrics['os.load_average'] = node['os']['load_average'][0]
    metrics['os.mem.free_in_bytes'] = node['os']['mem']['free_in_bytes']
    metrics['process.mem.resident_in_bytes'] = node['process']['mem']['resident_in_bytes']
    metrics['jvm.mem.heap_used_in_bytes'] = node['jvm']['mem']['heap_used_in_bytes']
    metrics['jvm.mem.non_heap_used_in_bytes'] = node['jvm']['mem']['non_heap_used_in_bytes']
    metrics['jvm.gc.collection_time_in_millis'] = node['jvm']['gc']['collection_time_in_millis']
    metrics.each do |k, v|
      output([config[:scheme], k].join("."), v, timestamp)
    end
    ok
  end

end