#!/usr/bin/env ruby
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# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
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#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
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require 'socket'

if ARGV.length < 2
  puts 'is_master execute a command when it determine that server is master'
  puts "Usage: #{$PROGRAM_NAME} [VIP|FILE] COMMAND"
  puts '  VIP     - IP address expected to be master'
  puts '  FILE    - File expected to be master'
  puts '  COMMAND - Command to execute if host is master'
  exit 2
end

expected = ARGV[0]
command  = ARGV[1..-1].join(' ')

if Socket.ip_address_list.map(&:ip_address).include?(expected) || File.exist?(expected)
  Kernel.exec(command)
else
  puts 'OK - I am slave, i going to sleep'
end