pluginaweek / has_emails

= has_emails

+has_emails+ adds support for emailing capabilities between ActiveRecord models.

== Resources

Announcement

* http://www.pluginaweek.org

Wiki

* http://wiki.pluginaweek.org/Has_emails

API

* http://api.pluginaweek.org/has_emails

Development

* http://dev.pluginaweek.org/browser/trunk/plugins/active_record/has/has_emails

Source

* http://svn.pluginaweek.org/trunk/plugins/active_record/has/has_emails

== Description

Emailing between users and other parts of a system is a fairly common feature in
web applications, especially for those that support social networking.  Emailing
doesn't necessarily need to be between users, but can also act as a way for the
web application to send notices and other notifications to users.

Rails already provides ActionMailer as a way of sending emails.  However, the
framework does not provide an easy way to persist emails, track their status, and
process them asynchronously.  Designing and building this type of framework can
become complex and cumbersome and takes away from the focus of the web application.
This plugin helps ease that process by providing a complete implementation for
sending and receiving emails to and between models in your application.

== Usage

=== Adding emailing support

If you want to use the built-in support for email addresses (using the EmailAddress
model), you can add emailing support for users like so:

  class User < ActiveRecord::Base
    has_email_address
    # has_email_addresses if you want to support multiple addresses
  end

On the other hand, if you already have the email address for users stored as a
column in your users table, you can add emailing support like so:

  class User < ActiveRecord::Base
    has_messages  :emails,
                    :message_class => 'Email'
  end

=== Creating new emails

  email = user.emails.build
  email.to << [user1, email_address1, 'someone@somewhere.com']
  email.subject = 'Hey!'
  email.body = 'Does anyone want to go out tonight?'
  email.deliver!

As can be seen in the above example, you can use Users, EmailAddresses, or even
Strings as recipients in emails.  Each will be automatically converted to the
EmailRecipient class so that it can be stored in the database.

=== Replying to emails

  reply = email.reply_to_all
  reply.body = "I'd love to go out!"
  reply.deliver!

=== Forwarding emails

  forward = email.forward
  forward.body = 'Interested?'
  forward.deliver!

=== External process messaging

In addition to delivering emails immediately, you can also *queue* emails so
that an external application processes and delivers them.  This is especially
useful when you want to asynchronously send e-mails so that it doesn't block the
user interface on your web application.

To queue emails for external processing, you can simply use the <tt>queue!</tt>
event, rather than <tt>deliver!</tt>.  This will indicate to any external processes
that the email is ready to be sent.  The external process can then invoke <tt>deliver!</tt>
whenever it is ready to send the queued email.

=== Running migrations

To migrate the tables required for this plugin, you can either run the
migration from the command line like so:

  rake db:migrate:plugins PLUGIN=has_emails

or (more ideally) generate a migration file that will integrate into your main
application's migration path:

  ruby script/generate plugin_migration has_emails

== Testing

Before you can run any tests, the following gems must be installed:
* plugin_test_helper[http://wiki.pluginaweek.org/Plugin_test_helper]
* dry_validity_assertions[http://wiki.pluginaweek.org/Dry_validity_assertions]

== Dependencies

This plugin depends on the presence of the following plugins:
* has_messages[http://wiki.pluginaweek.org/Has_messages]
* validates_as_email_address[http://wiki.pluginaweek.org/Validates_as_email_address]

This plugin is also a plugin+.  That means that it contains a slice of an
application, such as models and migrations.  To test or use a plugin+, you
must have the following plugins/gems installed:
* plugin_dependencies[http://wiki.pluginaweek.org/Plugin_dependencies]
* loaded_plugins[http://wiki.pluginaweek.org/Loaded_plugins]
* appable_plugins[http://wiki.pluginaweek.org/Appable_plugins]
* plugin_migrations[http://wiki.pluginaweek.org/Plugin_migrations]

Instead of installing each individual plugin+ feature, you can install them all
at once using the plugins+[http://wiki.pluginaweek.org/Plugins_plus] meta package,
which contains all additional features.