Premailer README¶ ↑

What is this?¶ ↑

For the best HTML e-mail delivery results, CSS should be inline. This is a huge pain and a simple newsletter becomes un-managable very quickly. This script is my solution.

• CSS styles are converted to inline style attributes Checks style and link[rel=stylesheet] tags and preserves existing inline attributes

• Relative paths are converted to absolute paths Checks links in href, src and CSS url('')

• CSS properties are checked against e-mail client capabilities Based on the Email Standards Project’s guides

• A plain text version is created Optional

Installation¶ ↑

Download the Premailer gem from GemCutter.

gem sources -a http://gemcutter.org
sudo gem install premailer

Example¶ ↑

premailer = Premailer.new('http://example.com/myfile.html', :warn_level => Premailer::Warnings::SAFE)

# Write the HTML output
fout = File.open("output.html", "w")
fout.puts premailer.to_inline_css
fout.close

# Write the plain-text output
fout = File.open("ouput.txt", "w")
fout.puts premailer.to_plain_text
fout.close

# Output any CSS warnings
premailer.warnings.each do |w|
  puts "#{w[:message]} (#{w[:level]}) may not render properly in #{w[:clients]}"
end

Contributions¶ ↑

Contributions are most welcome. Premailer was rotting away in a private SVN repository for too long and could use some TLC. Pull and patch to your heart’s content.

A few areas that are particularly in need of love:

• Testing suite There were unit tests but they were so funky that it was better to just strip them out.

• Test running Premailer on local files

• Create a binary file for easing command line use, allowing the output to be piped in *nix systems

• Ruby 1.9 testing

• Test with Rails

• Move un-repeated background images defined in CSS to <td background=""> for Outlook

• Correctly parse www.webstandards.org/files/acid2/test.html

Credits and code¶ ↑

Premailer is written in Ruby.

The web interface can be found at premailer.dialect.ca .

The source code can be found at github.com/alexdunae/premailer .

Written by Alex Dunae (dunae.ca, e-mail ‘code’ at the same domain), 2008-2009.