css_to_cdn.rb

s3_access = ""
s3_secret = ""
s3_bucket = ""
cdn_path  = "http://cloudfront.your.server.com"

desc "Swaps the local style.css file for a cdn hosted one"
task :css_to_cdn do
  puts "## Checking AWS Credentials..."
  unless s3_access && s3_secret
    puts "\n## ERROR: Please setup up both s3_access and s3_secret"
    next false
  end
  ENV['AWS_ACCESS_KEY_ID'] = s3_access
  ENV['AWS_SECRET_ACCESS_KEY'] = s3_secret
  puts "\n## Deploying website onto Amazon S3"
  s3 = AWS::S3.new
  bucket = s3.buckets[s3_bucket]
  
  file_path = "public/stylesheets/screen.css"
  bucket_path = file_path.sub('public/', '')
  puts "## Uploading \"#{file_path}\" to \"#{cdn_path}/#{bucket_path}\""
  fd = File.open(file_path)
  obj = bucket.objects[bucket_path]
  
  write = !obj.exists? || obj.last_modified < fd.mtime
  puts "  -> #{obj.public_url}" && obj.write(fd, :acl => :public_read) if write
  
  puts "## Swapping all relative references of 'href=\"/stylesheets/screen.css\"' for one hosted at \"#{cdn_path}\""
  files = %x[find #{public_dir} -type f -iname "*.html"].split
  files.map do |file_path|
    puts "  -> #{file_path}"
    text = File.read(file_path)
    replace = text.gsub("href=\"/stylesheets/screen.css\"", "href=\"#{cdn_path}/stylesheets/screen.css\"")
    File.open(file_path, "w") {|file| file.puts replace}
  end
end