SendGrid gem for Rails 3

SendGrid gem provides ActionMailer::Base extensions to use SendGrid API features in you emails. It extends ActionMailer with next methods:

substitute(patters_string, array_of_substitunion_strings)
uniq_args(hash_of_unique_args)
category(category_string)
open_tracking(enabled = true)
add_filter_setting(filter_name, setting_name, value)

Rails 3 configuration

In your Gemfile:

gem 'sendgrid-rails', '~> 2.0'

In config/initializers/mail.rb:

ActionMailer::Base.register_interceptor(SendGrid::MailInterceptor)

ActionMailer::Base.smtp_settings = {
  :address => 'smtp.sendgrid.net',
  :port => '25',
  :domain => 'example.com',
  :authentication => :plain,
  :user_name => 'login@example.com',
  :password => 'your password'
}

Overriding default recipient in standard SMTP header

Dummy recipient email used in sent email's “To” header and seen in received email's Received header. By default set to 'dummy@email.com'

In config/initializers/mail.rb:

SendGrid.configure do |config|
  config.dummy_recipient = 'noreply@example.com'
end

Usage examples

Adding multiple recipients:

class Mailer < ActionMailer::Base
  default :from => 'no-reply@example.com',
          :subject => 'An email sent via SendGrid'

  def email_with_multiple_recipients
    mail :to => %w(email1@email.com email2@email.com)
  end
end

Adding substitution vars

Mailer class definition:

class Mailer < ActionMailer::Base
  default :from => 'no-reply@example.com',
          :subject => 'An email sent via SendGrid with substitutions'

  def email_with_substitutions
    substitute '-user_name-', %w(User1 User2)

    mail :to => %w(email1@email.com email2@email.com), :body => "Hello, -user_name-!"
  end
end

Adding category

Mailer class definition:

class Mailer < ActionMailer::Base
  default :from => 'no-reply@example.com',
          :subject => 'An email sent via SendGrid with substitutions'

  def email_with_category
    category 'SendGridRocks'
    mail :to => 'email1@email.com'
  end
end

Apps (formerly called Filters)

Apps can be applied to any of your email messages and can be configured through SendGrid gem.

Open Tracking

Add an invisible image at the end of the email to track e-mail opens. If the email recipient has images enabled on the email client, a request to server for the invisible image is executed and an open is logged.

class Mailer < ActionMailer::Base
  default :from => 'no-reply@example.com',
          :subject => 'An email sent via SendGrid'

  def email_with_open_tracking_enabled
    open_tracking true
    mail :to => 'email@email.com'
  end
end

Change log

v2.0.4

  • CC and BCC are copied to SendGrid XSMTP-API header

v2.0.3

  • Ability to change “dummy_recipient” in config

v2.0.2

  • ApiHeader#to_json wraps array items with spaces

v2.0.1

  • Standard SMTP To attribute set to 'dummy@email.com' after recipients added to X-SMTPAPI header

v2.0

  • Using mail interceptor

  • ActionMailer::Base#add_recipients - removed

  • Standard SMTP To attribute get nullified after recipients added to X-SMTPAPI header