Convert some Dublin Core XML from DigiTool to CSV with Ruby

gistfile1.rb

#!/usr/bin/env ruby
# encoding: utf-8

require 'active_support/core_ext'
require 'pp'
require 'csv'
require 'nokogiri'

dc_terms = [ :contributor, :coverage, :creator, :date,
  :description, :format, :identifier, :language,
  :publisher, :relation, :rights, :source, 
  :subject, :title, :type, :medium ]

my_files = Dir.chdir(ARGV[0]) { Dir.glob("./*").map{|x| File.expand_path(x) } }

csv_string = CSV.generate do |csv|
  csv << dc_terms.map(&:to_s)
  my_files.each do |x|
    my_file = Nokogiri::XML(File.open(x))
    if my_file.at_xpath("//md[type='dc']/value")
      my_xml = Nokogiri::XML(my_file.at_xpath("//md[type='dc']/value").text)
      Hash.from_xml(my_xml.to_xml)["record"].tap do |o|
        csv << dc_terms.map{ |dct| [*o[dct.to_s]].join("|") }
      end
    end
  end
end
puts csv_string