Lotus::Mailer

Mail for Ruby applications.

Status

Contact

• Home page: http://lotusrb.org
• Mailing List: http://lotusrb.org/mailing-list
• API Doc: http://rdoc.info/gems/lotus-mailer
• Bugs/Issues: https://github.com/lotus/mailer/issues
• Support: http://stackoverflow.com/questions/tagged/lotus-ruby
• Chat: https://gitter.im/lotus/chat

Rubies

Lotus::Mailer supports Ruby (MRI) 2+.

Installation

Add this line to your application's Gemfile:

gem 'lotus-mailer'

And then execute:

$ bundle

Or install it yourself as:

$ gem install lotus-mailer

Usage

Conventions

• Templates are searched under Lotus::Mailer.configuration.root, set this value according to your app structure (eg. "app/templates").
• A mailer will look for a template with a file name that is composed by its full class name (eg. "articles/index").
• A template must have two concatenated extensions: one for the format and one for the engine (eg. ".html.erb").
• The framework must be loaded before rendering the first time: Lotus::Mailer.load!.

Mailers

A simple mailer looks like this:

require lotus/mailer

class InvoiceMailer
  include Lotus::Mailer
end

A mailer with .to and .from addresses and mailer delivery:

require lotus/mailer

Lotus::Mailer.configuration do
  delivery_method :smtp,
    address:              "smtp.gmail.com",
    port:                 587,
    domain:               "example.com",
    user_name:            ENV['SMTP_USERNAME'],
    password:             ENV['SMTP_PASSWORD'],
    authentication:       "plain",
    enable_starttls_auto: true
end.load!

class WelcomeMailer
  include Lotus::Mailer

  from    'noreply@sender.com'
  to      'noreply@recipient.com'
  subject 'Welcome'
end

WelcomeMailer.deliver

Locals

The set of objects passed in the deliver call are called locals and are avaliable inside the mailer and the template.

require lotus/mailer

User = Struct.new(:name, :username)
user = User.new('Luca', 'jodosha')

Lotus::Mailer.load!

class WelcomeMailer
  include Lotus::Mailer

  from    'noreply@sender.com'
  subject 'Welcome'
  to      :recipient

  private

  def recipient
    user.email
  end
end

InvoiceMailer.deliver(user: luca)

The corresponding erb file:

Hello <%= user.name %>!

Scope

All public methods defined in the mailer are accessible from the template:

require lotus/mailer

class WelcomeMailer
  include Lotus::Mailer

  from    'noreply@sender.com'
  to      'noreply@recipient.com'
  subject 'Welcome'

  def greeting
    'Ahoy'
  end
end

<h2><%= greeting %></h2>

Template

The template file must be located under the relevant root and must match the inflected snake case of the mailer class name.

# Given this root
Lotus::Mailer.configuration.root      # => #<Pathname:app/templates>

# For InvoiceMailer, it looks for:
#  * app/templates/invoice_mailer.html.erb
#  * app/templates/invoice_mailer.txt.erb

If we want to specify a different template, we can do:

class InvoiceMailer
  include Lotus::Mailer

  template 'invoice'
end

# It will look for:
#  * app/templates/invoice.html.erb
#  * app/templates/invoice.txt.erb

Engines

The builtin rendering engine is ERb.

This is the list of the supported engines. They are listed in order of higher precedence, for a given extension. For instance, if ERubis is loaded, it will be preferred over ERb to render .erb templates.

Engine	Extensions
Erubis	erb, rhtml, erubis
ERb	erb, rhtml
Redcarpet	markdown, mkd, md
RDiscount	markdown, mkd, md
Kramdown	markdown, mkd, md
Maruku	markdown, mkd, md
BlueCloth	markdown, mkd, md
Asciidoctor	ad, adoc, asciidoc
Builder	builder
CSV	rcsv
CoffeeScript	coffee
WikiCloth	wiki, mediawiki, mw
Creole	wiki, creole
Etanni	etn, etanni
Haml	haml
Less	less
Liquid	liquid
Markaby	mab
Nokogiri	nokogiri
Plain	html
RDoc	rdoc
Radius	radius
RedCloth	textile
Sass	sass
Scss	scss
Slim	slim
String	str
Yajl	yajl

Configuration

Lotus::Mailer can be configured with a DSL that determines its behavior. It supports a few options:

require 'lotus/mailer'

Lotus::Maler.configure do
  # Set the root path where to search for templates
  # Argument: String, Pathname, #to_pathname, defaults to the current directory
  #
  root '/path/to/root'

  # Set the default charset for emails
  # Argument: String, defaults to "UTF-8"
  #
  default_charset 'iso-8859'

  # Set the delivery method
  # Argument: Symbol
  # Argument: Hash, optional configurations
  delivery_method :stmp

Attachments

Attachments can be added with the following API:

class InvoiceMailer
  include Lotus::Mailer
  # ...

  def prepare
    mail.attachments['invoice.pdf'] = '/path/to/invoice.pdf'
    # or
    mail.attachments['invoice.pdf'] = File.read('/path/to/invoice.pdf')
  end
end

Delivery Method

The global delivery method is defined through the Lotus::Mailer configuration, as:

Lotus::Mailer.configuration do
  delivery_method :smtp
end

Lotus::Mailer.configuration do
  delivery_method :smtp, address: "localhost", port: 1025
end

Builtin options are:

• Exim (:exim)
• Sendmail (:sendmail)
• SMTP (:smtp, for local installations)
• SMTP Connection (:smtp_connection, via Net::SMTP - for remote installations)
• Test (:test, for testing purposes)

Custom Delivery Method

Developers can specify their own custom delivery policy:

require 'lotus/mailer'

class MandrillDeliveryMethod
  def initialize(options)
    @options = options
  end

  def deliver!(mail)
    # ...
  end
end

Lotus::Mailer.configure do
  delivery_method MandrillDeliveryMethod,
    username: ENV['MANDRILL_USERNAME'],
    password: ENV['MANDRILL_API_KEY']
end.load!

The class passed to .delivery_method must accept an optional set of options with the constructor (#initialize) and respond to #deliver!.

Multipart Delivery

All the email are sent as multipart messages by default. For a given mailer, the framework looks up for associated text (.txt) and HTML (.html) templates and render them.

InvoiceMailer.deliver               # delivers both text and html templates
InvoiceMailer.deliver(format: :txt) # delivers only text template

Please note that they aren't both mandatory, but at least one of them MUST be present.

Versioning

Lotus::Mailer uses Semantic Versioning 2.0.0

Copyright

Copyright © 2015 Luca Guidi – Released under MIT License