Rails app won't send mail (via sendmail) under JRuby

Question

After switching my Rails 2.3 app from MRI Ruby 1.8.7 to JRuby 1.6.5, the app is no longer able to send mail. I'm using ActionMailer like this:

class MessageMailer < ActionMailer::Base
  def message(msg, recipient, reply_to_email=nil)
    template = (msg.message_type.nil?) ? "default" : msg.message_type.name.downcase.gsub(' ', '_')

    recipients recipient
    subject msg.subject
    from (msg.sender.nil? or msg.sender.email.blank?) ? "\"no-reply\" <#{SYSTEM_EMAIL_ADDRESS}>" : msg.sender.email
    content_type "text/html"
    body render_message(template, :message => msg)
    reply_to reply_to_email || ((msg.sender.nil? or msg.sender.email.blank?) ? "\"no-reply\" <#{SYSTEM_EMAIL_ADDRESS}>" : msg.sender.email)
  end

  ...
end

MessageMailer.deliver_message(...)

That's probably irrelevant, since this all works under MRI Ruby 1.8.7.

The Rails app is configured to use sendmail in config/environments/production.rb:

config.action_mailer.delivery_method = :sendmail

What's more interesting are the sendmail logs (/var/log/mail.log):

# Sending mail under MRI Ruby 1.8.7
Jan  5 09:38:49 my sendmail[24755]: q05EcnCr024755: from=edwarda, size=310, class=0, nrcpts=1, msgid=<[email protected]>, relay=edwarda@localhost
Jan  5 09:38:49 my sm-mta[24757]: q05Ecn02024757: from=<[email protected]>, size=516, class=0, nrcpts=1, msgid=<[email protected]>, proto=ESMTP, daemon=MTA-v4, relay=localhost [127.0.0.1]
Jan  5 09:38:49 my sendmail[24755]: q05EcnCr024755: [email protected], ctladdr=edwarda (1011/1012), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30310, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (q05Ecn02024757 Message accepted for delivery)
Jan  5 09:38:49 my sm-mta[24759]: STARTTLS=client, relay=aspmx.l.google.com., version=TLSv1/SSLv3, verify=FAIL, cipher=RC4-SHA, bits=128/128
Jan  5 09:38:49 my sm-mta[24759]: q05Ecn02024757: to=<[email protected]>, ctladdr=<[email protected]> (1011/1012), delay=00:00:00, xdelay=00:00:00, mailer=esmtp, pri=120516, relay=aspmx.l.google.com. [74.125.45.27], dsn=2.0.0, stat=Sent (OK 1325774329 o43si18661797yhk.140)

# Sending mail under JRuby 1.6.5
Jan  5 11:10:26 my sendmail[7623]: q05GAQkH007623: from=edwarda, size=199, class=0, nrcpts=0, relay=edwarda@localhost

Note that the nrcpts (number of recipients) is 0 when I'm running JRuby and 1 when running 1.8.7.

I'm using the exact same code and gems, except I'm using these gems in addition for JRuby:

gem 'activerecord-jdbc-adapter', '<= 1.2.0', :require => false
gem 'activerecord-jdbcpostgresql-adapter', '<= 1.2.0', :require => 'jdbc_adapter'
gem 'ffi-ncurses'
gem 'jruby-openssl'
gem 'torquebox', '2.0.0.beta1', :platforms => 'jruby'
gem 'torquebox-rake-support', :platforms => 'jruby'
gem 'torquebox-capistrano-support', '2.0.0.beta1'

In case it's useful, this is my Gemfile.lock.

There is no interesting or unusual output in my Rails logs; only the usual success messages.

edit: I cannot reproduce this problem on my development (OSX) machine.

Any thoughts on why the recipients might be getting lost or how I might troubleshoot this?

Answer 1

This is related to a JRuby bug: http://jira.codehaus.org/browse/JRUBY-6162

Apparently IO.popen is closing prematurely when it tries to execute the sendmail command. Until this is fixed upstream, this monkey patch can be included in an initializer to work around the problem:

Rails 2:

module ActionMailer
  class Base
    def perform_delivery_sendmail(mail)
      sendmail_args = sendmail_settings[:arguments]
      sendmail_args += " -f \"#{mail['return-path']}\"" if mail['return-path']

      IO.popen("#{sendmail_settings[:location]} #{sendmail_args}", "r+") do |f| #r+ geht, w+ geht nicht richtig, bzw. nur manchmal
        f.puts mail.encoded.gsub(/\r/, '')
        f.close_write
        sleep 1 # <---- added this line in order to give sendmail some time to process
      end
    end
  end
end

Rails 3:

module Mail
  class Sendmail

    def initialize(values)
      self.settings = { :location       => '/usr/sbin/sendmail',
                        :arguments      => '-i -t' }.merge(values)
    end

    attr_accessor :settings

    def deliver!(mail)
      envelope_from = mail.return_path || mail.sender || mail.from_addrs.first
      return_path = "-f \"#{envelope_from.to_s.shellescape}\"" if envelope_from

      arguments = [settings[:arguments], return_path].compact.join(" ")

      Sendmail.call(settings[:location], arguments, mail.destinations.collect(&:shellescape).join(" "), mail)
    end

    def Sendmail.call(path, arguments, destinations, mail)
      IO.popen("#{path} #{arguments} #{destinations}", "r+") do |io|
        io.puts mail.encoded.to_lf
        io.close_write  # <------ changed this from flush to close_write
        sleep 1 # <-------- added this line
      end
    end
  end
end