Script to return list of masters. Useful in Bolt, for loops, and scripting

masters

#!/usr/bin/env ruby

require 'yaml'
require 'optparse'

options = {
  file: File.expand_path('masters.yaml'),
  type: nil,
  environment: nil
}

ARGV.options do |opts|
  opts.banner = 'Usage: masters [options]'
  opts.on('--file SERVER_LIST')          { |val| options[:file] = val }
  opts.on('--environment x,y,z', Array)  { |val| options[:environment] = val }
  opts.on('--type TYPE', %w[mom com])    { |val| options[:type] = val }
  begin
    opts.parse!
  rescue OptionParser::InvalidOption, OptionParser::InvalidArgument => e
    STDERR.puts e
    exit 1
  end
end

if File.exist?(options[:file])
  masters = YAML.load_file(options[:file])
else
  STDERR.puts "File does not exist: #{options[:file]}"
  exit 1
end

masters.each do |environment, types|
  # Skip the environment if it's not in the list of environments requested.
  next if options[:environment] && !options[:environment].include?(environment)

  types.each do |type, servers|
    # Skip the type (mom or com) if it's not the type requested.
    next if options[:type] && type != options[:type]
    puts servers
  end
end

masters.yaml

# environment: top-level key
# type: mom (masters of masters) or com (compile master)
---
production:
  mom: puppet1001.foo.org
  com:
    - puppet1029.foo.org
    - puppet1042.foo.org
    - puppet1012.foo.org
    - puppet1043.foo.org

qa:
  mom: non-prod-pup0013.lab.foo.org
  com:
    - non-prod-pup0012.lab.foo.org
    - non-prod-pup0014.lab.foo.org

dev:
  mom: non-prod-pup0011.lab.foo.org
  com:
    - non-prod-pup0010.lab.foo.org
    - non-prod-pup0010.lab.foo.org

Example usage: