Digestifier

A simple Rails engine for sending out email digests of activity.

Installation

Add this line to your application's Gemfile:

gem 'digestifier', '0.0.4'

Don't forget to bundle:

$ bundle

Then, add the migrations to your app and update your database accordingly:

$ rake digestifier:install:migrations db:migrate

Configuration

Create an initializer that sets up both a digest and the sender address:

# config/initializers/digestifier.rb

# Set the sender of your digest emails
Digestifier.sender = 'Hello <[email protected]>'

# Set the digest object to a constant so it can be referred to elsewhere.
DIGEST = Digestifier::Digest.new
# Set the lambda that returns objects for the digest. This takes a single
# argument - the time range - and should return a collection of objects. How
# you get this collection is up to you, but the example below is a decent
# starting point.
DIGEST.contents = lambda { |range|
  Article.where(created_at: range).order(:created_at)
}
# The digest recipients defaults to all User objects in your system. If you
# want to use a different class, or filter those objects, you can customise it:
DIGEST.recipients = lambda { User }
# The default frequency is once a day.
DIGEST.default_frequency = 24.hours

Sending emails

This will likely go in a rake task - but it's up to you.

Digestifier::Delivery.deliver DIGEST

If it does go in a rake task, ensure the task loads your Rails environment as well:

task :send_digest => :environment do
  Digestifier::Delivery.deliver DIGEST
end

You can test sending an email to a specific recipient using the following code:

Digestifier::Delivery.new(DIGEST, recipient).deliver

Unsubscribing

The default emails will include an unsubscribe link at the bottom - but this requires you to mount the engine in your config/routes.rb file:

mount Digestifier::Engine => '/digests'

You can mount it to wherever you like, of course.

Customising partial templates

This step is almost certainly essential: you'll want to customise how each item in your digest is presented. The partials for this should be located in app/views/digestifier/mailer, and use the item's class name, downcased and underscored (for example: _article.html.erb or _comment.html.haml).

What goes in these templates is completely up to you - the default is super-simple and almost certainly not enough for a decent digest:

<%= digest_item.name %>

digest_item will be available in your partial, but you can also refer to it using a downcased and underscored interpretation of the class (so, article and comment respectively in the example file names above).

Customising the main email

The main email template should probably be overwritten as well - just put your preferred view code in app/views/digestifier/mailer/digest.[html.erb|html.haml|etc].

The two instance variables you have access to are @recipient and @content_items. If you wish to use the Digestifier partial matching, something like this should do the trick:

<% @content_items.each do |item| %>
  <%= render_digest_partial item %>
<% end %>

Don't forget to include an unsubscribe link:

<%= link_to 'Unsubscribe', unsubscribe_url_for(@recipient) %>

Also: you'll very likely want to customise the email's subject - this is done via Rails' internationalisation:

en:
  digestifier:
    mailer:
      digest:
        subject: "The Latest News"

Customising the mailer

If you want to put your own Mailer, then this is certainly possible:

Digestifier.mailer = CustomMailer

Your new mailer class should respond to digest and accept the following arguments: recipient and content_items. If you're using the unsubscribe_url_for method, you'll want to include the helper that provides it:

class CustomMailer < ActionMailer::Base
  helper 'digestifier/unsubscribes'
  # And for partial matchers, if desired:
  helper 'digestifier/partial'

  # ...

Contributing

Fork it
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request