Change colours of a SVG image with Nokogiri.

svg_processing.rb

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

require "nokogiri"
require "fileutils"

# setup
required_colors = ["ff000", "006600", "003399"]

# main
Dir["*.svg"].each do |path|
  original = File.read(path)
  basename = File.basename(path).split(".").first
  document = Nokogiri::XML.parse(original)

  begin
    FileUtils.mkdir(basename)
  rescue Errno::EEXIST
  end

  Dir.chdir(basename) do
    required_colors.each do |color|
      File.open("#{color}.svg", "w") do |file|
        current = document.dup
        # current.xpath("//*[@fill]").set(:fill, "##{color}")
        # current.xpath("/svg/g/path[not(@fill)]").set(:fill, "##{color}") # doesn't work for some reason
        current.css("path:not([fill])").set(:fill, "##{color}")
        file.puts(current)
      end
    end
  end
end