haml directory watcher

haml_watch.rb

#!/usr/bin/ruby1.8
# Script to watch a directory for any changes to a haml file and compile it.
#
# Changes to a file named like _partial.haml will compile any haml files that
# reference the partial i.e. any that contain
# =Haml::Engine.new(File.read("/path/to/_partial.haml")).render
#
# USAGE: ruby haml_watch.rb <directory_to_watch>
#
# Original by Blake Smith / http://blakesmith.github.com/2010/09/05/haml-directory-watcher.html
# Modifications by fin / http://fin.io
# Support for partials workflow by cahrehn
#

require 'rubygems'
require 'fssm'
require 'haml'


def rebuild_haml(base, relative)
  input_file = File.join(base, relative)
  input = File.read(input_file)
  engine = Haml::Engine.new(input)
  output_file = File.join(base, relative.gsub('.haml', '.html'))
  output = open(output_file, 'w')
  output.write(engine.render)
  output.close
  puts "Rendered #{relative} to #{relative.gsub('.haml', '.html')}"
end


def rebuild_partials(base, relative)
  Dir.foreach(base) do |item|
    next if item == '.' or item == '..'
    if item.match(/haml$/) and
        File.readlines("#{base}/#{item}").grep(/#{relative}/).size > 0 then
      rebuild_haml(base, item)
    end
  end
end


directory = ARGV.first
FSSM.monitor(directory, '**/*.haml') do
  update do |base, relative|
    if relative.match(/^_/) then
      rebuild_haml(base, relative)
      rebuild_partials(base, relative)
    else
      rebuild_haml(base, relative)    
    end
  end
end