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Add note for custom mailer view paths in action mailer guide. [ci skip]
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871 lines
31 KiB
Markdown
**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON https://guides.rubyonrails.org.**
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Action Mailer Basics
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====================
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This guide provides you with all you need to get started in sending and
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receiving emails from and to your application, and many internals of Action
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Mailer. It also covers how to test your mailers.
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After reading this guide, you will know:
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* How to send and receive email within a Rails application.
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* How to generate and edit an Action Mailer class and mailer view.
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* How to configure Action Mailer for your environment.
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* How to test your Action Mailer classes.
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--------------------------------------------------------------------------------
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Introduction
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------------
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Action Mailer allows you to send emails from your application using mailer classes
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and views.
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#### Mailers are similar to controllers
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They inherit from `ActionMailer::Base` and live in `app/mailers`. Mailers also work
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very similarly to controllers. Some examples of similarities are enumerated below.
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Mailers have:
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* Actions, and also, associated views that appear in `app/views`.
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* Instance variables that are accessible in views.
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* The ability to utilise layouts and partials.
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* The ability to access a params hash.
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Sending Emails
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--------------
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This section will provide a step-by-step guide to creating a mailer and its
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views.
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### Walkthrough to Generating a Mailer
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#### Create the Mailer
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```bash
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$ rails generate mailer UserMailer
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create app/mailers/user_mailer.rb
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create app/mailers/application_mailer.rb
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invoke erb
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create app/views/user_mailer
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create app/views/layouts/mailer.text.erb
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create app/views/layouts/mailer.html.erb
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invoke test_unit
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create test/mailers/user_mailer_test.rb
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create test/mailers/previews/user_mailer_preview.rb
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```
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```ruby
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# app/mailers/application_mailer.rb
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class ApplicationMailer < ActionMailer::Base
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default from: "from@example.com"
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layout 'mailer'
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end
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# app/mailers/user_mailer.rb
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class UserMailer < ApplicationMailer
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end
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```
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As you can see, you can generate mailers just like you use other generators with
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Rails.
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If you didn't want to use a generator, you could create your own file inside of
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`app/mailers`, just make sure that it inherits from `ActionMailer::Base`:
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```ruby
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class MyMailer < ActionMailer::Base
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end
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```
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#### Edit the Mailer
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Mailers have methods called "actions" and they use views to structure their content.
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Where a controller generates content like HTML to send back to the client, a Mailer
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creates a message to be delivered via email.
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`app/mailers/user_mailer.rb` contains an empty mailer:
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```ruby
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class UserMailer < ApplicationMailer
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end
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```
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Let's add a method called `welcome_email`, that will send an email to the user's
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registered email address:
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```ruby
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class UserMailer < ApplicationMailer
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default from: 'notifications@example.com'
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def welcome_email
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@user = params[:user]
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@url = 'http://example.com/login'
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mail(to: @user.email, subject: 'Welcome to My Awesome Site')
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end
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end
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```
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Here is a quick explanation of the items presented in the preceding method. For
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a full list of all available options, please have a look further down at the
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Complete List of Action Mailer user-settable attributes section.
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* `default Hash` - This is a hash of default values for any email you send from
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this mailer. In this case we are setting the `:from` header to a value for all
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messages in this class. This can be overridden on a per-email basis.
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* `mail` - The actual email message, we are passing the `:to` and `:subject`
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headers in.
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#### Create a Mailer View
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Create a file called `welcome_email.html.erb` in `app/views/user_mailer/`. This
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will be the template used for the email, formatted in HTML:
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```html+erb
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<!DOCTYPE html>
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<html>
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<head>
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<meta content='text/html; charset=UTF-8' http-equiv='Content-Type' />
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</head>
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<body>
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<h1>Welcome to example.com, <%= @user.name %></h1>
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<p>
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You have successfully signed up to example.com,
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your username is: <%= @user.login %>.<br>
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</p>
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<p>
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To login to the site, just follow this link: <%= @url %>.
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</p>
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<p>Thanks for joining and have a great day!</p>
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</body>
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</html>
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```
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Let's also make a text part for this email. Not all clients prefer HTML emails,
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and so sending both is best practice. To do this, create a file called
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`welcome_email.text.erb` in `app/views/user_mailer/`:
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```erb
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Welcome to example.com, <%= @user.name %>
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===============================================
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You have successfully signed up to example.com,
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your username is: <%= @user.login %>.
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To login to the site, just follow this link: <%= @url %>.
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Thanks for joining and have a great day!
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```
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When you call the `mail` method now, Action Mailer will detect the two templates
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(text and HTML) and automatically generate a `multipart/alternative` email.
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#### Calling the Mailer
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Mailers are really just another way to render a view. Instead of rendering a
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view and sending it over the HTTP protocol, they are just sending it out through
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the email protocols instead. Due to this, it makes sense to just have your
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controller tell the Mailer to send an email when a user is successfully created.
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Setting this up is painfully simple.
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First, let's create a simple `User` scaffold:
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```bash
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$ rails generate scaffold user name email login
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$ rails db:migrate
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```
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Now that we have a user model to play with, we will just edit the
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`app/controllers/users_controller.rb` make it instruct the `UserMailer` to deliver
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an email to the newly created user by editing the create action and inserting a
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call to `UserMailer.with(user: @user).welcome_email` right after the user is successfully saved.
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Action Mailer is nicely integrated with Active Job so you can send emails outside
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of the request-response cycle, so the user doesn't have to wait on it:
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```ruby
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class UsersController < ApplicationController
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# POST /users
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# POST /users.json
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def create
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@user = User.new(params[:user])
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respond_to do |format|
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if @user.save
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# Tell the UserMailer to send a welcome email after save
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UserMailer.with(user: @user).welcome_email.deliver_later
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format.html { redirect_to(@user, notice: 'User was successfully created.') }
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format.json { render json: @user, status: :created, location: @user }
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else
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format.html { render action: 'new' }
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format.json { render json: @user.errors, status: :unprocessable_entity }
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end
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end
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end
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end
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```
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NOTE: Active Job's default behavior is to execute jobs via the `:async` adapter. So, you can use
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`deliver_later` now to send emails asynchronously.
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Active Job's default adapter runs jobs with an in-process thread pool.
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It's well-suited for the development/test environments, since it doesn't require
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any external infrastructure, but it's a poor fit for production since it drops
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pending jobs on restart.
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If you need a persistent backend, you will need to use an Active Job adapter
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that has a persistent backend (Sidekiq, Resque, etc).
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NOTE: When calling `deliver_later` the job will be placed under `mailers` queue. Make sure Active Job adapter support it otherwise the job may be silently ignored preventing email delivery. You can change that by specifying `config.action_mailer.deliver_later_queue_name` option.
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If you want to send emails right away (from a cronjob for example) just call
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`deliver_now`:
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```ruby
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class SendWeeklySummary
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def run
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User.find_each do |user|
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UserMailer.with(user: user).weekly_summary.deliver_now
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end
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end
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end
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```
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Any key value pair passed to `with` just becomes the `params` for the mailer
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action. So `with(user: @user, account: @user.account)` makes `params[:user]` and
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`params[:account]` available in the mailer action. Just like controllers have
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params.
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The method `welcome_email` returns an `ActionMailer::MessageDelivery` object which
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can then just be told `deliver_now` or `deliver_later` to send itself out. The
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`ActionMailer::MessageDelivery` object is just a wrapper around a `Mail::Message`. If
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you want to inspect, alter, or do anything else with the `Mail::Message` object you can
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access it with the `message` method on the `ActionMailer::MessageDelivery` object.
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### Auto encoding header values
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Action Mailer handles the auto encoding of multibyte characters inside of
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headers and bodies.
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For more complex examples such as defining alternate character sets or
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self-encoding text first, please refer to the
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[Mail](https://github.com/mikel/mail) library.
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### Complete List of Action Mailer Methods
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There are just three methods that you need to send pretty much any email
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message:
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* `headers` - Specifies any header on the email you want. You can pass a hash of
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header field names and value pairs, or you can call `headers[:field_name] =
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'value'`.
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* `attachments` - Allows you to add attachments to your email. For example,
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`attachments['file-name.jpg'] = File.read('file-name.jpg')`.
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* `mail` - Sends the actual email itself. You can pass in headers as a hash to
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the mail method as a parameter, mail will then create an email, either plain
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text, or multipart, depending on what email templates you have defined.
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#### Adding Attachments
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Action Mailer makes it very easy to add attachments.
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* Pass the file name and content and Action Mailer and the
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[Mail gem](https://github.com/mikel/mail) will automatically guess the
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mime_type, set the encoding, and create the attachment.
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```ruby
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attachments['filename.jpg'] = File.read('/path/to/filename.jpg')
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```
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When the `mail` method will be triggered, it will send a multipart email with
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an attachment, properly nested with the top level being `multipart/mixed` and
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the first part being a `multipart/alternative` containing the plain text and
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HTML email messages.
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NOTE: Mail will automatically Base64 encode an attachment. If you want something
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different, encode your content and pass in the encoded content and encoding in a
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`Hash` to the `attachments` method.
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* Pass the file name and specify headers and content and Action Mailer and Mail
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will use the settings you pass in.
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```ruby
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encoded_content = SpecialEncode(File.read('/path/to/filename.jpg'))
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attachments['filename.jpg'] = {
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mime_type: 'application/gzip',
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encoding: 'SpecialEncoding',
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content: encoded_content
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}
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```
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NOTE: If you specify an encoding, Mail will assume that your content is already
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encoded and not try to Base64 encode it.
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#### Making Inline Attachments
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Action Mailer 3.0 makes inline attachments, which involved a lot of hacking in pre 3.0 versions, much simpler and trivial as they should be.
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* First, to tell Mail to turn an attachment into an inline attachment, you just call `#inline` on the attachments method within your Mailer:
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```ruby
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def welcome
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attachments.inline['image.jpg'] = File.read('/path/to/image.jpg')
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end
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```
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* Then in your view, you can just reference `attachments` as a hash and specify
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which attachment you want to show, calling `url` on it and then passing the
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result into the `image_tag` method:
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```html+erb
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<p>Hello there, this is our image</p>
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<%= image_tag attachments['image.jpg'].url %>
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```
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* As this is a standard call to `image_tag` you can pass in an options hash
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after the attachment URL as you could for any other image:
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```html+erb
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<p>Hello there, this is our image</p>
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<%= image_tag attachments['image.jpg'].url, alt: 'My Photo', class: 'photos' %>
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```
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#### Sending Email To Multiple Recipients
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It is possible to send email to one or more recipients in one email (e.g.,
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informing all admins of a new signup) by setting the list of emails to the `:to`
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key. The list of emails can be an array of email addresses or a single string
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with the addresses separated by commas.
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```ruby
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class AdminMailer < ApplicationMailer
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default to: -> { Admin.pluck(:email) },
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from: 'notification@example.com'
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def new_registration(user)
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@user = user
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mail(subject: "New User Signup: #{@user.email}")
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end
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end
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```
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The same format can be used to set carbon copy (Cc:) and blind carbon copy
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(Bcc:) recipients, by using the `:cc` and `:bcc` keys respectively.
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#### Sending Email With Name
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Sometimes you wish to show the name of the person instead of just their email
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address when they receive the email. The trick to doing that is to format the
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email address in the format `"Full Name" <email>`.
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```ruby
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def welcome_email
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@user = params[:user]
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email_with_name = %("#{@user.name}" <#{@user.email}>)
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mail(to: email_with_name, subject: 'Welcome to My Awesome Site')
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end
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```
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### Mailer Views
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Mailer views are located in the `app/views/name_of_mailer_class` directory. The
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specific mailer view is known to the class because its name is the same as the
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mailer method. In our example from above, our mailer view for the
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`welcome_email` method will be in `app/views/user_mailer/welcome_email.html.erb`
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for the HTML version and `welcome_email.text.erb` for the plain text version.
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To change the default mailer view for your action you do something like:
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```ruby
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class UserMailer < ApplicationMailer
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default from: 'notifications@example.com'
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def welcome_email
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@user = params[:user]
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@url = 'http://example.com/login'
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mail(to: @user.email,
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subject: 'Welcome to My Awesome Site',
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template_path: 'notifications',
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template_name: 'another')
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end
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end
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```
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In this case it will look for templates at `app/views/notifications` with name
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`another`. You can also specify an array of paths for `template_path`, and they
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will be searched in order.
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If you want more flexibility you can also pass a block and render specific
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templates or even render inline or text without using a template file:
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```ruby
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class UserMailer < ApplicationMailer
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default from: 'notifications@example.com'
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def welcome_email
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@user = params[:user]
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@url = 'http://example.com/login'
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mail(to: @user.email,
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subject: 'Welcome to My Awesome Site') do |format|
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format.html { render 'another_template' }
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format.text { render plain: 'Render text' }
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end
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end
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end
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```
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This will render the template 'another_template.html.erb' for the HTML part and
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use the rendered text for the text part. The render command is the same one used
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inside of Action Controller, so you can use all the same options, such as
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`:text`, `:inline` etc.
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If you would like to render a template located outside of the default `app/views/mailer_name/` directory, you can apply the `prepend_view_path`, like so:
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```ruby
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class UserMailer < ApplicationMailer
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prepend_view_path "custom/path/to/mailer/view"
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# This will try to load "custom/path/to/mailer/view/welcome_email" template
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def welcome_email
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# ...
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end
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end
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```
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You can also consider using the [append_view_path](https://guides.rubyonrails.org/action_view_overview.html#view-paths) method.
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#### Caching mailer view
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You can perform fragment caching in mailer views like in application views using the `cache` method.
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```
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<% cache do %>
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<%= @company.name %>
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<% end %>
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```
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And in order to use this feature, you need to configure your application with this:
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```
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config.action_mailer.perform_caching = true
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```
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Fragment caching is also supported in multipart emails.
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Read more about caching in the [Rails caching guide](caching_with_rails.html).
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### Action Mailer Layouts
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Just like controller views, you can also have mailer layouts. The layout name
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needs to be the same as your mailer, such as `user_mailer.html.erb` and
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`user_mailer.text.erb` to be automatically recognized by your mailer as a
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layout.
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In order to use a different file, call `layout` in your mailer:
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```ruby
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class UserMailer < ApplicationMailer
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layout 'awesome' # use awesome.(html|text).erb as the layout
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end
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```
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Just like with controller views, use `yield` to render the view inside the
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layout.
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You can also pass in a `layout: 'layout_name'` option to the render call inside
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the format block to specify different layouts for different formats:
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```ruby
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class UserMailer < ApplicationMailer
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def welcome_email
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mail(to: params[:user].email) do |format|
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format.html { render layout: 'my_layout' }
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format.text
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end
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end
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end
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```
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Will render the HTML part using the `my_layout.html.erb` file and the text part
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with the usual `user_mailer.text.erb` file if it exists.
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### Previewing Emails
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Action Mailer previews provide a way to see how emails look by visiting a
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special URL that renders them. In the above example, the preview class for
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`UserMailer` should be named `UserMailerPreview` and located in
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`test/mailers/previews/user_mailer_preview.rb`. To see the preview of
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`welcome_email`, implement a method that has the same name and call
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`UserMailer.welcome_email`:
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```ruby
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class UserMailerPreview < ActionMailer::Preview
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def welcome_email
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UserMailer.with(user: User.first).welcome_email
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end
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end
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```
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Then the preview will be available in <http://localhost:3000/rails/mailers/user_mailer/welcome_email>.
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If you change something in `app/views/user_mailer/welcome_email.html.erb`
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or the mailer itself, it'll automatically reload and render it so you can
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visually see the new style instantly. A list of previews are also available
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in <http://localhost:3000/rails/mailers>.
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|
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By default, these preview classes live in `test/mailers/previews`.
|
|
This can be configured using the `preview_path` option. For example, if you
|
|
want to change it to `lib/mailer_previews`, you can configure it in
|
|
`config/application.rb`:
|
|
|
|
```ruby
|
|
config.action_mailer.preview_path = "#{Rails.root}/lib/mailer_previews"
|
|
```
|
|
|
|
### Generating URLs in Action Mailer Views
|
|
|
|
Unlike controllers, the mailer instance doesn't have any context about the
|
|
incoming request so you'll need to provide the `:host` parameter yourself.
|
|
|
|
As the `:host` usually is consistent across the application you can configure it
|
|
globally in `config/application.rb`:
|
|
|
|
```ruby
|
|
config.action_mailer.default_url_options = { host: 'example.com' }
|
|
```
|
|
|
|
Because of this behavior you cannot use any of the `*_path` helpers inside of
|
|
an email. Instead you will need to use the associated `*_url` helper. For example
|
|
instead of using
|
|
|
|
```
|
|
<%= link_to 'welcome', welcome_path %>
|
|
```
|
|
|
|
You will need to use:
|
|
|
|
```
|
|
<%= link_to 'welcome', welcome_url %>
|
|
```
|
|
|
|
By using the full URL, your links will now work in your emails.
|
|
|
|
#### Generating URLs with `url_for`
|
|
|
|
`url_for` generates a full URL by default in templates.
|
|
|
|
If you did not configure the `:host` option globally make sure to pass it to
|
|
`url_for`.
|
|
|
|
|
|
```erb
|
|
<%= url_for(host: 'example.com',
|
|
controller: 'welcome',
|
|
action: 'greeting') %>
|
|
```
|
|
|
|
#### Generating URLs with Named Routes
|
|
|
|
Email clients have no web context and so paths have no base URL to form complete
|
|
web addresses. Thus, you should always use the "_url" variant of named route
|
|
helpers.
|
|
|
|
If you did not configure the `:host` option globally make sure to pass it to the
|
|
url helper.
|
|
|
|
```erb
|
|
<%= user_url(@user, host: 'example.com') %>
|
|
```
|
|
|
|
NOTE: non-`GET` links require [rails-ujs](https://github.com/rails/rails/blob/master/actionview/app/assets/javascripts) or
|
|
[jQuery UJS](https://github.com/rails/jquery-ujs), and won't work in mailer templates.
|
|
They will result in normal `GET` requests.
|
|
|
|
### Adding images in Action Mailer Views
|
|
|
|
Unlike controllers, the mailer instance doesn't have any context about the
|
|
incoming request so you'll need to provide the `:asset_host` parameter yourself.
|
|
|
|
As the `:asset_host` usually is consistent across the application you can
|
|
configure it globally in `config/application.rb`:
|
|
|
|
```ruby
|
|
config.action_mailer.asset_host = 'http://example.com'
|
|
```
|
|
|
|
Now you can display an image inside your email.
|
|
|
|
```ruby
|
|
<%= image_tag 'image.jpg' %>
|
|
```
|
|
|
|
### Sending Multipart Emails
|
|
|
|
Action Mailer will automatically send multipart emails if you have different
|
|
templates for the same action. So, for our `UserMailer` example, if you have
|
|
`welcome_email.text.erb` and `welcome_email.html.erb` in
|
|
`app/views/user_mailer`, Action Mailer will automatically send a multipart email
|
|
with the HTML and text versions setup as different parts.
|
|
|
|
The order of the parts getting inserted is determined by the `:parts_order`
|
|
inside of the `ActionMailer::Base.default` method.
|
|
|
|
### Sending Emails with Dynamic Delivery Options
|
|
|
|
If you wish to override the default delivery options (e.g. SMTP credentials)
|
|
while delivering emails, you can do this using `delivery_method_options` in the
|
|
mailer action.
|
|
|
|
```ruby
|
|
class UserMailer < ApplicationMailer
|
|
def welcome_email
|
|
@user = params[:user]
|
|
@url = user_url(@user)
|
|
delivery_options = { user_name: params[:company].smtp_user,
|
|
password: params[:company].smtp_password,
|
|
address: params[:company].smtp_host }
|
|
mail(to: @user.email,
|
|
subject: "Please see the Terms and Conditions attached",
|
|
delivery_method_options: delivery_options)
|
|
end
|
|
end
|
|
```
|
|
|
|
### Sending Emails without Template Rendering
|
|
|
|
There may be cases in which you want to skip the template rendering step and
|
|
supply the email body as a string. You can achieve this using the `:body`
|
|
option. In such cases don't forget to add the `:content_type` option. Rails
|
|
will default to `text/plain` otherwise.
|
|
|
|
```ruby
|
|
class UserMailer < ApplicationMailer
|
|
def welcome_email
|
|
mail(to: params[:user].email,
|
|
body: params[:email_body],
|
|
content_type: "text/html",
|
|
subject: "Already rendered!")
|
|
end
|
|
end
|
|
```
|
|
|
|
Receiving Emails
|
|
----------------
|
|
|
|
Receiving and parsing emails with Action Mailer can be a rather complex
|
|
endeavor. Before your email reaches your Rails app, you would have had to
|
|
configure your system to somehow forward emails to your app, which needs to be
|
|
listening for that. So, to receive emails in your Rails app you'll need to:
|
|
|
|
* Implement a `receive` method in your mailer.
|
|
|
|
* Configure your email server to forward emails from the address(es) you would
|
|
like your app to receive to `/path/to/app/bin/rails runner
|
|
'UserMailer.receive(STDIN.read)'`.
|
|
|
|
Once a method called `receive` is defined in any mailer, Action Mailer will
|
|
parse the raw incoming email into an email object, decode it, instantiate a new
|
|
mailer, and pass the email object to the mailer `receive` instance
|
|
method. Here's an example:
|
|
|
|
```ruby
|
|
class UserMailer < ApplicationMailer
|
|
def receive(email)
|
|
page = Page.find_by(address: email.to.first)
|
|
page.emails.create(
|
|
subject: email.subject,
|
|
body: email.body
|
|
)
|
|
|
|
if email.has_attachments?
|
|
email.attachments.each do |attachment|
|
|
page.attachments.create({
|
|
file: attachment,
|
|
description: email.subject
|
|
})
|
|
end
|
|
end
|
|
end
|
|
end
|
|
```
|
|
|
|
Action Mailer Callbacks
|
|
---------------------------
|
|
|
|
Action Mailer allows for you to specify a `before_action`, `after_action` and
|
|
`around_action`.
|
|
|
|
* Filters can be specified with a block or a symbol to a method in the mailer
|
|
class similar to controllers.
|
|
|
|
* You could use a `before_action` to populate the mail object with defaults,
|
|
delivery_method_options or insert default headers and attachments.
|
|
|
|
```ruby
|
|
class InvitationsMailer < ApplicationMailer
|
|
before_action { @inviter, @invitee = params[:inviter], params[:invitee] }
|
|
before_action { @account = params[:inviter].account }
|
|
|
|
default to: -> { @invitee.email_address },
|
|
from: -> { common_address(@inviter) },
|
|
reply_to: -> { @inviter.email_address_with_name }
|
|
|
|
def account_invitation
|
|
mail subject: "#{@inviter.name} invited you to their Basecamp (#{@account.name})"
|
|
end
|
|
|
|
def project_invitation
|
|
@project = params[:project]
|
|
@summarizer = ProjectInvitationSummarizer.new(@project.bucket)
|
|
|
|
mail subject: "#{@inviter.name.familiar} added you to a project in Basecamp (#{@account.name})"
|
|
end
|
|
end
|
|
```
|
|
|
|
* You could use an `after_action` to do similar setup as a `before_action` but
|
|
using instance variables set in your mailer action.
|
|
|
|
```ruby
|
|
class UserMailer < ApplicationMailer
|
|
before_action { @business, @user = params[:business], params[:user] }
|
|
|
|
after_action :set_delivery_options,
|
|
:prevent_delivery_to_guests,
|
|
:set_business_headers
|
|
|
|
def feedback_message
|
|
end
|
|
|
|
def campaign_message
|
|
end
|
|
|
|
private
|
|
|
|
def set_delivery_options
|
|
# You have access to the mail instance,
|
|
# @business and @user instance variables here
|
|
if @business && @business.has_smtp_settings?
|
|
mail.delivery_method.settings.merge!(@business.smtp_settings)
|
|
end
|
|
end
|
|
|
|
def prevent_delivery_to_guests
|
|
if @user && @user.guest?
|
|
mail.perform_deliveries = false
|
|
end
|
|
end
|
|
|
|
def set_business_headers
|
|
if @business
|
|
headers["X-SMTPAPI-CATEGORY"] = @business.code
|
|
end
|
|
end
|
|
end
|
|
```
|
|
|
|
* Mailer Filters abort further processing if body is set to a non-nil value.
|
|
|
|
Using Action Mailer Helpers
|
|
---------------------------
|
|
|
|
Action Mailer now just inherits from `AbstractController`, so you have access to
|
|
the same generic helpers as you do in Action Controller.
|
|
|
|
Action Mailer Configuration
|
|
---------------------------
|
|
|
|
The following configuration options are best made in one of the environment
|
|
files (environment.rb, production.rb, etc...)
|
|
|
|
| Configuration | Description |
|
|
|---------------|-------------|
|
|
|`logger`|Generates information on the mailing run if available. Can be set to `nil` for no logging. Compatible with both Ruby's own `Logger` and `Log4r` loggers.|
|
|
|`smtp_settings`|Allows detailed configuration for `:smtp` delivery method:<ul><li>`:address` - Allows you to use a remote mail server. Just change it from its default `"localhost"` setting.</li><li>`:port` - On the off chance that your mail server doesn't run on port 25, you can change it.</li><li>`:domain` - If you need to specify a HELO domain, you can do it here.</li><li>`:user_name` - If your mail server requires authentication, set the username in this setting.</li><li>`:password` - If your mail server requires authentication, set the password in this setting.</li><li>`:authentication` - If your mail server requires authentication, you need to specify the authentication type here. This is a symbol and one of `:plain` (will send the password in the clear), `:login` (will send password Base64 encoded) or `:cram_md5` (combines a Challenge/Response mechanism to exchange information and a cryptographic Message Digest 5 algorithm to hash important information)</li><li>`:enable_starttls_auto` - Detects if STARTTLS is enabled in your SMTP server and starts to use it. Defaults to `true`.</li><li>`:openssl_verify_mode` - When using TLS, you can set how OpenSSL checks the certificate. This is really useful if you need to validate a self-signed and/or a wildcard certificate. You can use the name of an OpenSSL verify constant ('none' or 'peer') or directly the constant (`OpenSSL::SSL::VERIFY_NONE` or `OpenSSL::SSL::VERIFY_PEER`).</li></ul>|
|
|
|`sendmail_settings`|Allows you to override options for the `:sendmail` delivery method.<ul><li>`:location` - The location of the sendmail executable. Defaults to `/usr/sbin/sendmail`.</li><li>`:arguments` - The command line arguments to be passed to sendmail. Defaults to `-i`.</li></ul>|
|
|
|`raise_delivery_errors`|Whether or not errors should be raised if the email fails to be delivered. This only works if the external email server is configured for immediate delivery.|
|
|
|`delivery_method`|Defines a delivery method. Possible values are:<ul><li>`:smtp` (default), can be configured by using `config.action_mailer.smtp_settings`.</li><li>`:sendmail`, can be configured by using `config.action_mailer.sendmail_settings`.</li><li>`:file`: save emails to files; can be configured by using `config.action_mailer.file_settings`.</li><li>`:test`: save emails to `ActionMailer::Base.deliveries` array.</li></ul>See [API docs](http://api.rubyonrails.org/classes/ActionMailer/Base.html) for more info.|
|
|
|`perform_deliveries`|Determines whether deliveries are actually carried out when the `deliver` method is invoked on the Mail message. By default they are, but this can be turned off to help functional testing.|
|
|
|`deliveries`|Keeps an array of all the emails sent out through the Action Mailer with delivery_method :test. Most useful for unit and functional testing.|
|
|
|`default_options`|Allows you to set default values for the `mail` method options (`:from`, `:reply_to`, etc.).|
|
|
|
|
For a complete writeup of possible configurations see the
|
|
[Configuring Action Mailer](configuring.html#configuring-action-mailer) in
|
|
our Configuring Rails Applications guide.
|
|
|
|
### Example Action Mailer Configuration
|
|
|
|
An example would be adding the following to your appropriate
|
|
`config/environments/$RAILS_ENV.rb` file:
|
|
|
|
```ruby
|
|
config.action_mailer.delivery_method = :sendmail
|
|
# Defaults to:
|
|
# config.action_mailer.sendmail_settings = {
|
|
# location: '/usr/sbin/sendmail',
|
|
# arguments: '-i'
|
|
# }
|
|
config.action_mailer.perform_deliveries = true
|
|
config.action_mailer.raise_delivery_errors = true
|
|
config.action_mailer.default_options = {from: 'no-reply@example.com'}
|
|
```
|
|
|
|
### Action Mailer Configuration for Gmail
|
|
|
|
As Action Mailer now uses the [Mail gem](https://github.com/mikel/mail), this
|
|
becomes as simple as adding to your `config/environments/$RAILS_ENV.rb` file:
|
|
|
|
```ruby
|
|
config.action_mailer.delivery_method = :smtp
|
|
config.action_mailer.smtp_settings = {
|
|
address: 'smtp.gmail.com',
|
|
port: 587,
|
|
domain: 'example.com',
|
|
user_name: '<username>',
|
|
password: '<password>',
|
|
authentication: 'plain',
|
|
enable_starttls_auto: true }
|
|
```
|
|
NOTE: As of July 15, 2014, Google increased [its security measures](https://support.google.com/accounts/answer/6010255) and now blocks attempts from apps it deems less secure.
|
|
You can change your Gmail settings [here](https://www.google.com/settings/security/lesssecureapps) to allow the attempts. If your Gmail account has 2-factor authentication enabled,
|
|
then you will need to set an [app password](https://myaccount.google.com/apppasswords) and use that instead of your regular password. Alternatively, you can
|
|
use another ESP to send email by replacing 'smtp.gmail.com' above with the address of your provider.
|
|
|
|
Mailer Testing
|
|
--------------
|
|
|
|
You can find detailed instructions on how to test your mailers in the
|
|
[testing guide](testing.html#testing-your-mailers).
|
|
|
|
Intercepting Emails
|
|
-------------------
|
|
|
|
There are situations where you need to edit an email before it's
|
|
delivered. Fortunately Action Mailer provides hooks to intercept every
|
|
email. You can register an interceptor to make modifications to mail messages
|
|
right before they are handed to the delivery agents.
|
|
|
|
```ruby
|
|
class SandboxEmailInterceptor
|
|
def self.delivering_email(message)
|
|
message.to = ['sandbox@example.com']
|
|
end
|
|
end
|
|
```
|
|
|
|
Before the interceptor can do its job you need to register it with the Action
|
|
Mailer framework. You can do this in an initializer file
|
|
`config/initializers/sandbox_email_interceptor.rb`
|
|
|
|
```ruby
|
|
if Rails.env.staging?
|
|
ActionMailer::Base.register_interceptor(SandboxEmailInterceptor)
|
|
end
|
|
```
|
|
|
|
NOTE: The example above uses a custom environment called "staging" for a
|
|
production like server but for testing purposes. You can read
|
|
[Creating Rails environments](configuring.html#creating-rails-environments)
|
|
for more information about custom Rails environments.
|