#!/usr/bin/env ruby
require 'elasticsearch'


client_node = ARGV[0]

client = Elasticsearch::Client.new host: client_node

clients = client.nodes.info process: true

clients['nodes'].each do |node|
        node_id = node[0]
        puts clients['nodes'][node_id]['host'] if clients['nodes'][node_id]['attributes']['master']== "true"
end