mailman_guide

constants.rb

if Rails.env == "production"
  MAILMAN_USER     = "something@production.com"
  MAILMAN_PASSWORD = "pasword123"
else
  MAILMAN_USER     = "something@staging.com"
  MAILMAN_PASSWORD = "password321"
end

deploy.rb

namespace :mailman do
  desc "Mailman::Start"
  task :start, :roles => [:app] do
    run "cd #{current_path};RAILS_ENV=#{rack_env} bundle exec script/mailman_daemon start"
  end
  
  desc "Mailman::Stop"
  task :stop, :roles => [:app] do
    run "cd #{current_path};RAILS_ENV=#{rack_env} bundle exec script/mailman_daemon stop"
  end
  
  desc "Mailman::Restart"
  task :restart, :roles => [:app] do
    mailman.stop
    mailman.start
  end
end

Gemfile

gem 'daemons'
gem 'mailman', require: false
gem 'maildir'
gem 'mail'

incoming_mail.rb

class IncomingMail
  def initialize(message, params)
    @user = User.where(email: message.from).first rescue nil
    @message = message
    @params = params
  end

  def process(method)
    begin
      if spam_test #### this is a good place to filter unwanted mail.
        self.send method
      end
    rescue Exception => e
      Mailman.logger.error "Exception occurred while receiving message:\n#{@message}"
      Mailman.logger.error [e, *e.backtrace].join("\n")
    end
  end

  def spam_test
    if @user
      return true
    else
      Mailman.logger.error "Mail from #{@message.from.first} is unsolicited. Message ignored."
      return false
    end
  end

  def some_other_param_test(object)
    ### test
  end

  def default
    # create default action for emails from valid users.
    Mailman.logger.info 'Message matched the default route. Message ignored'
  end

  def method_for_route_one
    @interesting_param = @params[:interesting]
    if some_other_param_test(@interesting_param)
      if ## some Rails environment method
        Mailman.logger.info "#{@user.name} performed something useful."
      end
    else
      Mailman.logger.error "Something went wrong, here's useful debugging detail."
    end
  end

  def method_for_route_two
    @interesting_param = @params[:interesting]
    if some_other_param_test(@interesting_param)
      if ## some Rails environment method
        Mailman.logger.info "#{@user.name} performed something else."
      end
    else
      Mailman.logger.error "Something went wrong, here's another useful debugging detail."
    end
  end
end

incoming_mail_spec.rb

require 'spec_helper'
require 'maildir'

def send_test_mail
  @mail = Mail.new(from: @from_address, to: @to_address, subject: @subject, body: @body)
  @sent = @maildir.add(@mail)
  sleep 2
end

describe ReceivedMail do

  before(:each) do
      @maildir = Maildir.new('tmp/test_maildir')
      @maildir.serializer = Maildir::Serializer::Mail.new

      @other_variable = Object.new
  end

  describe "Mail received by the mailman server" do
    before(:each) do
      @from_address = 'from@default.com'
      @to_address = 'to@default.com'
      @subject = 'default subject'
      @body = 'default body text'
    end

    it "should achieve something" do
      pending
    end
  end
end

mailman_daemon.rb

#!/usr/bin/env ruby

require 'rubygems'
require "bundler/setup"
require 'daemons'

Daemons.run('script/mailman_server')

mailman_server.rb

#!/usr/bin/env ruby

require "rubygems"
require "bundler/setup"
require "mailman"

ENV["RAILS_ENV"] ||= "test"
require File.dirname(__FILE__) + "/../config/environment"

Mailman.config.ignore_stdin = true
Mailman.config.logger = Logger.new File.expand_path("../../log/mailman_#{Rails.env}.log", __FILE__)

if Rails.env == 'test'
  Mailman.config.maildir = File.expand_path("../../tmp/test_maildir", __FILE__)
else
  Mailman.config.logger = Logger.new File.expand_path("../../log/mailman.log", __FILE__)
  Mailman.config.poll_interval = 15
  Mailman.config.pop3 = {
    server: 'pop.gmail.com', port: 995, ssl: true,
    username: MAILMAN_USER,
    password: MAILMAN_PASSWORD
  }
end

Mailman::Application.run do
  to('route_one_%interesting%@%domain%') do
    IncomingMail.new(message, params).process(:method_for_route_one)
  end
  to('someone_else@%domain%').subject('%interesting%') do
    IncomingMail.new(message, params).process(:method_for_route_two)
  end
  default do
    IncomingMail.new(message, params).process(:default)
  end
end