ERB Email Templates

ERB Email Templates - 07 Dec 2012

I was playing around with ERB the other day and ended up designing a really simple e-mail system with templates. Here’s the system I created.

class Email
  def deliver
    EmailApi.new(email_options).deliver
  end

  def template
    File.open "templates/#{handle}.erb"
  end

  def message
    ERB.new(template.read).result(binding)
  end

  def handle
    self.class.to_s.downcase
  end
end

class SignupEmail < Email
  attr_accessor :user
  def initialize user
    @user = user
  end

  def email_options
    { :body => message,
      :to => user.email,
      :subject => subject
    }
  end

  def subject
    "Welcome #{user.name}"
  end
end

In order to send a sign up email to a new user, you would call:

SignupEmail.new(user).deliver

EmailApi would represent the service you’re using to deliver e-mails in your application. The body of the e-mail would be created from the signupemail.erb file in the templates directory.

By passing binding to ERB, you’re able to access the @user variable in your template.