ActionMailer in standalone apps

Today someone in #ruby-lang asked if you could use Rails' ActionMailer also in standalone ruby applications. That user left after a short time and the question stayed unanswered, although it is my opinion quite interesting :) So I started digging a little bit through the documentation and came up with a quite basic solution which actually holds no real suprises. 

require 'rubygems'
   require 'pp'
   require_gem 'actionmailer'
   ActionMailer::Base.template_root = 'templates'
   ActionMailer::Base.delivery_method = :test
   class TestMailer < ActionMailer::Base
     def test
       @recipients = 're@domain.com'
       @subject = 'Hello World'
       @from = 'sender@domain.com'
     end
   end
   if $0 == FILE
     TestMailer.deliver_test
     ActionMailer::Base.deliveries.each do |mail| 
       puts "#{'='*60}"
       puts "Subject: #{mail.subject}"
       puts "From: #{mail.from}"
       puts "To: #{mail.to}"
       puts "#{'-'*60}"
       puts "#{mail.body}"
     end
   end

As in Rails you simply create an ActionMailer subclass and do the deliver_action thing with it. The only thing that is slightly different here, is that you have to specify a template_root directory. The rest of the configuration should be the same as for its use in a Rails webapp (for details please read the manual) In this case I use the 'templates' folder in the same directory as the script (actually in the pwd but anyway ;)).

So for this example you would have to have following folder structure 

./templates
   ./templates/test_mailer
   ./templates/test_mailer/test.rhtml
   ./test.rb

Running this script should give you the expected mail :)

Note: I haven't tested it with anything but the :test delivery_method, so perhaps there are some hidden problems :)