Using Callbacks in Rails 3 ActionMailer

When working with ActionMailer (Rails 3) it feels so similar to how controllers work that I thought it was odd that I couldn’t use callbacks such as before_filter or after_filter. While there are drop in gems or examples showing how to use interceptors I figured there had to be a way to reuse callbacks.

Luckily, I came across an accepted pull request that includes callbacks in ActionMailer but only for Rails 4. After reviewing the commit its very easy to add support for Rails 3 since all we need to do is include the AbstractController::Callbacks module in our mailer class and from there we can define our callbacks.

The example below shows how I resolved an issue where I needed to change the recipient address for any outgoing emails when in the staging environment.

class Mailer < ActionMailer::Base
  include AbstractController::Callbacks
  after_filter :send_to_admin_if_staging
  def send_to_admin_if_staging
    if Rails.env.staging? = ''

Besides access to message we also have access to mail in callbacks. This is useful if you prefer to stop email delivery or perhaps change other mail settings.

after_filter :stop_delivery_if_staging

def stop_delivery_if_staging
  if Rails.env.staging?
    mail.perform_deliveries = false

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