Basic Sample of Action Mailer with RSpec in Rails4

This article shows how to generate action mailer class, to setup cofiguration, to test the function.

🐰 Generate Mailer Class

At first, you should create Action Mailer Class.

$ rails g mailer message hello
      create  app/mailers/message.rb
      create  app/mailers/application_mailer.rb
      invoke  haml
      create    app/views/message
      create    app/views/message/hello.text.haml
      invoke  rspec
      create    spec/mailers/message_spec.rb
      create    spec/fixtures/message/hello
      create    spec/mailers/previews/message_preview.rb

🍣 Mailer Code

You can customize your mail content to app/mailer/message_mailer.rb:

# app/mailer/message_mailer.rb
class MessageMailer < ActionMailer::Base
  default from: 'noreply@exmpale.com'

  def hello(name)
    @name = name
    mail to: 'send_to@example.com', subject: 'Hello'
  end
end

🎂 Configuration

Following configuration is for development:

# config/environments/development.rb
AppName::Application.configure do
  config.action_mailer.raise_delivery_errors = true
  
  config.action_mailer.default_url_options = { host: "localhost", port: 3000 }
  config.action_mailer.delivery_method = :smtp
  config.action_mailer.smtp_settings = {
    address: "SMTP MAIL SERVER",
    port: 587,
    domain: 'DOMAIN',
    user_name: "USER NAME FOR AUTHORIZATION TO MAIL SERVER",
    password: "USER PASSWORD FOR AUTHORIZATION TO MAIL SERVER"
  }
end

In addition, a test configuration is as follows:

# config/environments/test.rb
AppName::Application.configure do
  config.action_mailer.delivery_method = :test
end

🐡 RSpec

These specs should get you what you want.

# spec/mailers/message_mailer_spec.rb
require 'spec_helper'

describe MessageMailer do
  describe 'hello' do
    let(:name) { 'John' } 
    let(:mail) { described_class.hello(name).deliver_now }

    it 'renders the subject' do
      expect(mail.subject).to eql('Hello')
    end

    it 'renders the receiver email' do
      expect(mail.to).to eql(['send_to@example.com'])
    end

    it 'renders the sender email' do
      expect(mail.from).to eql(['noreply@exmpale.com'])
    end

    it 'assigns @name' do
      expect(mail.body.encoded).to match(name)
    end
  end
end

😼 Special Thanks

• ruby on rails - ActionMailer testing with rspec - Stack Overflow

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