vehicle_email.rb

class VehicleEmail
  include ActiveModel::Validations
  include ActiveModel::Conversion
  extend ActiveModel::Naming
  attr_accessor :recipients, :subject, :message, :vehicle_id

  validates_presence_of :subject, :message, :vehicle_id, :recipients

  def deliver_from(admin_user)
    if valid?
      recipients.each do |recipient|
        first_name = recipient[:first_name]
        last_name = recipient[:last_name]
        email = recipient[:email]
        UserMailer.delay.vehicle_email(:first_name => first_name,
                                       :last_name => last_name,
                                       :to => "#{first_name} #{last_name} <#{email}>",
                                       :from => "#{admin_user.first_name} #{admin_user.last_name} <#{admin_user.email}>",
                                       :sender => admin_user.email,
                                       :subject => subject,
                                       :message => message,
                                       :vehicle_id => vehicle_id)
      end
    else
      false
    end
  end


  def initialize(attributes = {})
    attributes.each do |name, value|
      send("#{name}=", value)
    end
  end

  def persisted?
    false
  end
end

vehicle_email_spec.rb

require 'spec_helper'

describe VehicleEmail do
  before :each do
    Delayed::Worker.delay_jobs = false
  end

  it 'is initialized with attributes hash' do
    vehicle_email = VehicleEmail.new(:subject => 'Take a look at this vehicle', :message => 'Hello', :vehicle_id => 777)
    vehicle_email.subject.should == 'Take a look at this vehicle'
    vehicle_email.message.should == 'Hello'
    vehicle_email.vehicle_id.should == 777
  end

  it 'delivers an email for each recipient' do
    admin_user = AdminUser.make

    UserMailer.stub_chain(:vehicle_email, :deliver)
    UserMailer.should_receive(:vehicle_email).twice

    vehicle_email = VehicleEmail.new(:subject => 'Take a look at this vehicle',
                                     :message => 'Hello',
                                     :vehicle_id => 777,
                                     :recipients => [
                                                     {
                                                       :first_name => 'John',
                                                       :last_name => 'Locke',
                                                       :email => 'john@locke.com'
                                                     },
                                                     {
                                                       :first_name => 'Bill',
                                                       :last_name => 'Murray',
                                                       :email => 'bill@murray.com'
                                                       
                                                     }
                                                    ]
                                     )
    vehicle_email.deliver_from admin_user
  end

  it "doesn't deliver an email with invalid options" do
    admin_user = AdminUser.make
    
    vehicle_email = VehicleEmail.new(:subject => 'Take a look at this vehicle',
                                     :message => 'Hello',
                                     :vehicle_id => 777
                                     )
    vehicle_email.should_not be_valid
    vehicle_email.deliver_from(admin_user).should be_false
  end
end