December 11, 2008

Posted by John

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Using Gmail to Send Email With Rails

I know this has been covered before but since it was suggested, I thought I would mention it here. Previously, I showed how to receive email in your Rails apps using Gmail, so it only makes sense that I would also show how to send email with Gmail.

Caveat emptor

First things first. I would not recommend using Gmail for something important that sends a lot of email. If you are going to be sending a lot of email, take PJ’s advice and use AuthSMTP or some other similar service. If, however, you are setting up something small and don’t feel like setting up Postfix or dropping some benjamins, Gmail works just fine.

Add An Initializer (or Gem)

As you may or may not know, Gmail requires tls, but net/smtp and thus ActionMailer, do not support tls out of the box. Luckily, there is a chunk of code that is floating all over the internets that adds this functionality. I typically put this code in config/initializers/smtp_tls.rb.

I so rarely use this that I haven’t taken the time to gem it up. Thankfully, Jason Perry did and posted so in a comment below. If you would rather have the gem dependency than the initializer, you can add the following to your environment.rb file.

config.gem "ambethia-smtp-tls", :lib => "smtp-tls", :source => ""

Configure Production SMTP Settings

Then, once I have the initializer in place, I add the following to the bottom of config/environments/production.rb.

config.action_mailer.smtp_settings = {
  :address        => "",
  :port           => 587,
  :domain         => "",
  :authentication => :plain,
  :user_name      => "",
  :password       => "banana"

The End

Sorry, that is the end. From this point on, just script/generate mailer as you normally would. In development mode, your emails will show up in your log file and in production, they will be sent using Gmail’s smtp settings. That is really all you need to know. Hope this helps!


  1. Instead of putting that “vendor” code in an initializer in all your apps, just gem install this:

    And put this in environment.rb:

      config.gem "ambethia-smtp-tls", :lib => "smtp-tls", :source => ""

    I wrapped up that same “bit-o-code” that’s been floating around to make it a little more reusable. I hate having to google around for it everytime I setup mailers.


  2. Yes, alas, I have been too lazy to gem this up as I very rarely use it. Thanks for doing the work!

  3. If you receive the following error: “ArgumentError: wrong number of arguments (3 for 2)” see my post for solving it.

  4. David Mathers David Mathers

    Dec 13, 2008

    Beware, I used this for a day and was losing at least 5% of emails into the ether. That was with fairly light usage.

  5. Beware, Gmail imposes a send limit of 500 recipients per day, or 2000 if you’re on a paid account. Their solution? Open multiple accounts and spread the load among all of them.,, etc.

  6. @David – I haven’t noticed that but thanks for mentioning it.

    @rick – Good point. Exactly why I mention not using it if you are going to send a lot of email. I would only use Gmail if I was sending < 50 emails a day. Most of the apps I use it for maybe send 5-10 a day and only during certain parts of the year so it works out just fine.

  7. Worth noting though that if you are running Rails 2.2 and Ruby 1.8.7, then it just works!

  8. @tekin – Sweet. I did not know that.

  9. Thanks for sharing!

  10. Thanks a lot!!!

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Authored by John Nunemaker (Noo-neh-maker), a programmer who has fallen deeply in love with Ruby. Learn More.


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