yieldbot/sensu-yieldbot-plugins

#! /usr/bin/env ruby
#
# Checks ElasticSearch shard allocation setting status
# ===
#
# DESCRIPTION:
#   Checks the ElasticSearch shard allocation persistent and transient settings
#   and will return status based on a difference in those settings.
#
# OUTPUT:
#   plain-text
#
# PLATFORMS:
#   Linux
#
# DEPENDENCIES:
#   gem: sensu-plugin
#   gem: rest-client
#
# #YELLOW
# needs usage
# USAGE:
#
#
# NOTES:
#
# LICENSE:
#   Copyright 2014 Yieldbot, Inc  <devops@yieldbot.com>
#   Released under the same terms as Sensu (the MIT license); see LICENSE
#   for details.
#
# rubocop:disable all

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

#
# == Elastic Search Shard Allocation Status
#
class ESShardAllocationStatus < Sensu::Plugin::Check::CLI
  option :scheme,
         description: 'URI scheme',
         long: '--scheme SCHEME',
         default: 'http'

  option :server,
         description: 'Elasticsearch server',
         short: '-s SERVER',
         long: '--server SERVER',
         default: 'localhost'

  option :port,
         description: 'Port',
         short: '-p PORT',
         long: '--port PORT',
         default: '9200'

  def get_es_resource(resource)
    r = RestClient::Resource.new("#{config[:scheme]}://#{config[:server]}:#{config[:port]}/#{resource}", timeout: 45)
    JSON.parse(r.get)
  rescue Errno::ECONNREFUSED
    warning 'Connection refused'
  rescue RestClient::RequestTimeout
    warning 'Connection timed out'
  end

  def master?
    state = get_es_resource('/_cluster/state?filter_routing_table=true&filter_metadata=true&filter_indices=true&filter_blocks=true&filter_nodes=true')
    local = get_es_resource('/_nodes/_local')
    local['nodes'].keys.first == state['master_node']
  end

  def get_status(type)
    settings = get_es_resource('/_cluster/settings')
    # Get the status for the given type, or default to 'all'
    # which is the ES default
    begin
      settings[type]['cluster']['routing']['allocation']['enable'].downcase
    rescue
      'all'
    end
  end

  # #YELLOW
  # method has too many lines
  def run
    if master?
      transient   = get_status('transient')
      persistent  = get_status('persistent')

      if transient == persistent
        ok "Persistent and transient allocation match:  #{persistent}"
      else
        critical "Persistent(#{persistent}) and transient(#{transient}) \
        shard allocation do not match."
      end
    else
      ok 'Not the master'
    end
  end
end