Parse Cheffile in Ruby

parse_cheffile.rb

#!/usr/bin/env ruby

class CookbookSource
  attr_reader :name, :options

  def initialize(name, options = {})
    @name = name
    @options = options
  end
end

class Cheffile
  def self.from_file(file)
    content = File.read(file)
    object = new(file)
    object.load(content)
  end

  attr_reader :file, :site, :cookbooks

  def initialize(file)
    @file = file
    @site = nil
    @cookbooks = Array.new
  end

  def site(site)
    @site = site
  end

  def cookbook(*args)
    options = args.last.is_a?(Hash) ? args.pop : Hash.new
    name, constraint = args
    options[:constraint] = constraint
    @cookbooks << CookbookSource.new(name, options)
  end

  def load(content)
    instance_eval(content)
    self
  rescue => e
    raise "An error occurred while reading the Cheffile: #{e}"
  end
end


filename = ARGV.first || 'Cheffile'
cheffile = Cheffile.from_file(filename)
cheffile.cookbooks.each do |cookbook|
  puts "#{cookbook.name.ljust(30)}#{cookbook.options.inspect}"
end