popper.rb

require 'eventmachine'
require 'net/pop'

class Popper 
  attr_accessor :pop, :read_messages

  def initialize(hostname, port, user, password)
    @pop = Net::POP3.start(hostname, port, user, password)
    @read_messages = []
    load_message_ids
  end

  def load_message_ids
    histfile = File.open("popper.ids", "r")
    histfile.each {|line| @read_messages << line.chomp }
  end

  def save_message_ids
    histfile = File.open("popper.ids", "w")
    @read_messages.each {|id| histfile.print id + "\n" }
    histfile.close
  end

  def unread?(id)
    !(@read_messages.include? id)
  end

  def inject_message(data)
    email = EM::Protocols::SmtpClient.send(
      :domain => "foo.com",
      :host => 'localhost',
      :port => 2525, # optional, defaults 25
      :starttls => false, # use ssl
      :from => "foo@bar.com",
      :to => ["bar@foo.com"],
      :header => {"Subject" => ""},
      :body => data
   )
   email.callback { puts 'Email sent!' }
   email.errback{ |e| puts 'Email failed!' }
  end
    
  def process
    @pop.mails.select { |m| unread?(m.unique_id) }.each do |m|
      inject_message(m.pop)
      @read_messages << m.unique_id
    end
    @pop.finish
    save_message_ids
    @read_messages
  end
end

EM.run do
  EM::add_periodic_timer(60) do
    EM.defer(proc { Popper.new("mail.foo.com", 110, "user", "pass").process }, proc {|result| p result})
  end
end