Premailer convert toolchain

inliner.rb

#!/usr/bin/ruby

require 'premailer'

in_filename = ARGV[0]
out_filename = ARGV[1]

if in_filename.nil?
  puts "Usage: ruby convert.rb <in_filename> <out_filename>"
  return
end

if out_filename.nil?
  puts "Usage: ruby convert.rb <in_filename> <out_filename>"
  return
end

TEMP_FILENAME = 'temp.html'
REMOVE_LINE_TAG = "<!-- EXCLUDE -->"
INSERT_CSS_TAG = "/* INCLUDE:"

def get_css_filename_from_css_tag(line)
  start_index = line.index(':') + 1
  end_index = line.rindex('*') - start_index
  return line.slice(start_index, end_index).strip
end

File.open(TEMP_FILENAME, 'w') do |fout_html|
  File.open(in_filename) do |fin_html|
    while (line = fin_html.gets)
      if not line.include? REMOVE_LINE_TAG
        fout_html.puts line
      end

      if line.include? INSERT_CSS_TAG
        css_filename = get_css_filename_from_css_tag(line)
        css_content = File.read(css_filename)
        fout_html.puts css_content
      end
    end
  end
end

premailer = Premailer.new(TEMP_FILENAME)

File.open(out_filename, 'w') do |fout|
  fout.puts premailer.to_inline_css
end

File.delete(TEMP_FILENAME)

Makefile

SRCS = password_reset_token-template.html
OBJS = $(SRCS:-template.html=.html)

all: $(OBJS)

$(OBJS):
	ruby inliner.rb $(@:.html=-template.html) $@

clean:
	rm -rf $(OBJS)

configure:
	gem install premailer

salted.css

    /* CLIENT-SPECIFIC STYLES */
    #outlook a{padding:0;} /* Force Outlook to provide a "view in browser" message */
    .ReadMsgBody{width:100%;} .ExternalClass{width:100%;} /* Force Hotmail to display emails at full width */
    .ExternalClass, .ExternalClass p, .ExternalClass span, .ExternalClass font, .ExternalClass td, .ExternalClass div {line-height: 100%;} /* Force Hotmail to display normal line spacing */
    body, table, td, a{-webkit-text-size-adjust:100%; -ms-text-size-adjust:100%;} /* Prevent WebKit and Windows mobile changing default text sizes */
    table, td{mso-table-lspace:0pt; mso-table-rspace:0pt;} /* Remove spacing between tables in Outlook 2007 and up */
    img{-ms-interpolation-mode:bicubic;} /* Allow smoother rendering of resized image in Internet Explorer */
    /* RESET STYLES */
    body{margin:0; padding:0;}
    img{border:0; height:auto; line-height:100%; outline:none; text-decoration:none;}
    table{border-collapse:collapse !important;}
    body{height:100% !important; margin:0; padding:0; width:100% !important;}
    /* iOS BLUE LINKS */
    .appleBody a {color:#68440a; text-decoration: none;}
    .appleFooter a {color:#999999; text-decoration: none;}
    /* MOBILE STYLES */
    @media screen and (max-width: 525px) {
        /* ALLOWS FOR FLUID TABLES */
        table[class="wrapper"]{
          width:100% !important;
        }
        /* ADJUSTS LAYOUT OF LOGO IMAGE */
        td[class="logo"]{
          text-align: left;
          padding: 20px 0 20px 0 !important;
        }
        td[class="logo"] img{
          margin:0 auto!important;
        }
        /* USE THESE CLASSES TO HIDE CONTENT ON MOBILE */
        td[class="mobile-hide"]{
          display:none;}
        img[class="mobile-hide"]{
          display: none !important;
        }
        img[class="img-max"]{
          max-width: 100% !important;
          height:auto !important;
        }
        /* FULL-WIDTH TABLES */
        table[class="responsive-table"]{
          width:100%!important;
        }
        /* UTILITY CLASSES FOR ADJUSTING PADDING ON MOBILE */
        td[class="padding"]{
          padding: 10px 5% 15px 5% !important;
        }
        td[class="padding-copy"]{
          padding: 10px 5% 10px 5% !important;
          text-align: center;
        }
        td[class="padding-meta"]{
          padding: 30px 5% 0px 5% !important;
          text-align: center;
        }
        td[class="no-pad"]{
          padding: 0 0 20px 0 !important;
        }
        td[class="no-padding"]{
          padding: 0 !important;
        }
        td[class="section-padding"]{
          padding: 50px 15px 50px 15px !important;
        }
        td[class="section-padding-bottom-image"]{
          padding: 50px 15px 0 15px !important;
        }
        /* ADJUST BUTTONS ON MOBILE */
        td[class="mobile-wrapper"]{
            padding: 10px 5% 15px 5% !important;
        }
        table[class="mobile-button-container"]{
            margin:0 auto;
            width:100% !important;
        }
        a[class="mobile-button"]{
            width:80% !important;
            padding: 15px !important;
            border: 0 !important;
            font-size: 16px !important;
        }
    }