Send an email using Ruby's standard lib.

smtp_send.rb

require 'net/smtp'

host = 'smtp.gmail.com'
port = 587
from = '[email protected]'
password = 'secret'
just_test = false
to = '[email protected]'

msgstr = <<END_OF_MESSAGE
From: #{from}
To: #{to}
Subject: testing Net::SMTP

Message body here.
END_OF_MESSAGE

smtp = Net::SMTP.new(host, port)
smtp.set_debug_output $stderr
smtp.enable_starttls_auto
if just_test
  begin
    smtp.start('localhost', from, password, :login)
    smtp.finish
    puts "TEST OK"
  rescue Net::SMTPAuthenticationError
    puts "TEST FAILED"
  end
else
  smtp.start('localhost', from, password, :login) do |smtp|
    smtp.send_message msgstr, from, to
  end
end