Question

I’ve got several methods I call repeatedly across a couple ActionMailer instances, and I’d like to move them into a module so that I can include them as a group and DRY things up.

module SendgridSettings
 open_tracking true
 add_filter_setting("subscriptiontrack", "enable", 1)
 add_filter_setting("subscriptiontrack","replace","{{ unsubscribe_url }}")
 uniq_args({'id' => email.id, 'organization_id' => organization.id})
 substitute '{{ person.first_name }}', recipients
 set_credentials(organization)
end

Here’s the relevant mailer code:

class NewChargeMailer < ActionMailer::Base
  def charge_email(recipient, transaction, organization)
  include SendgridSettings

I’m getting the error undefined methodopen_tracking’ for SendgridSettings:Module`, because it seems to be applying the methods on the module, not the object that is including it.

Most of the examples I see online are about defining methods in the module, then using them in the inheriting object. I guess I’m trying to do the opposite, and haven’t been able to find a way to do that. Is such a thing possible, or even a good idea? I’m not wedded to using a module, it just seemed like the natural way to isolate the methods that need to be called sometimes as a group.

Answer 1

You may need to do something like this:

module SendgridSettings

  def self.included(base)
    base.class_eval do
      before_filter :default_settings
    end
  end

  def default_settings
    #write your code here
  end

end

It is also possible that this code could work inside the module too:

::ActionMailer::Base.register_interceptor(self)

You can also use ActionMailer like a controller too:

module ActionMailer
  class Base < AbstractController::Base
    #...
  end
end

Sources:
Rails 3: Trying to extend Action Mailer with a module
https://github.com/weppos/actionmailer_with_request/blob/master/lib/actionmailer_with_request.rb
http://railsdispatch.com/posts/actionmailer