Compressing static svg files for the rails asset pipeline

compressed_svg.rb

# I used https://github.com/eliotsykes/rack-zippy to serve gzipped static assets. 
# By default the rails asset pipeline was not compressing any static svg files, 
# so I did the following to achive that.
#
# First create a rake task that will fine and compress svg files.
# File: lib/tasks/assets_svg_compress.rake
namespace :assets do
  task :svg_compress => :environment do
    svg_files = Dir["./public/**/*.svg"]
    svg_files.each do |file|
      puts "Compressing #{file}"
      Zlib::GzipWriter.open("#{file}.gz") do |file_gz|
        File.open(file) do |fp|
          while chunk = fp.read(16*1024) do
            file_gz.write chunk
          end
        end
        file_gz.close
      end
    end
  end
end

# Then enhance the normal `assets:precomiple` task by giving it another action. 
# See http://ruby-doc.org/stdlib-2.2.0/libdoc/rake/rdoc/Rake/Task.html#method-i-enhance
#
# File: lib/tasks/assets_precompile.rake
Rake::Task['assets:precompile'].enhance do
  Rake::Task['assets:svg_compress'].invoke
end

# Now rack-zippy will serve up compressed svg files.