How can I send emails in Rails 3 using the recipient's locale?

Question

How can I send mails in a mailer using the recipient\'s locale. I have the preferred locale for each user in the database. Notice this is different from the current locale (I18n

Answer 1

Here's an updated version that also supports the '.key' short-hand notation, so you don't have to spell out each key in its entirety.

http://github.com/larspind/i18n_action_mailer

Answer 2

None of the above is really working since the version 3 to translate both subject and content and be sure that the locale is reseted back to the original one... so I did the following (all mailer inherit from that class:

class ResourceMailer < ActionMailer::Base

  def mail(headers={}, &block)
    I18n.locale = mail_locale
    super
  ensure
    reset_locale
  end

  def i18n_subject(options = {})
    I18n.locale = mail_locale
    mailer_scope = self.class.mailer_name.gsub('/', '.')
    I18n.t(:subject, options.merge(:scope => [mailer_scope, action_name], :default => action_name.humanize))
  ensure
    reset_locale
  end  

  def set_locale(locale)
    @mail_locale = locale
  end

  protected

  def mail_locale
    @mail_locale || I18n.locale
  end

  def reset_locale
    I18n.locale = I18n.default_locale
  end

end

You just need to set the locale before you call the mail() method:

set_locale @user.locale

You can use the i18n_subject method which scope the current path so everything is structured:

mail(:subject => i18n_subject(:name => @user.name)

Answer 3

The problem with the mentioned plugins are that they don't work in all situations, for example doing User.human_name or User.human_attribute_name(...) will not translate correctly. The following is the easiest and guaranteed method to work:

stick this somewhere (in initializers or a plugin):

  module I18nActionMailer
    def self.included(base)
      base.class_eval do
        include InstanceMethods
        alias_method_chain :create!, :locale
      end
    end

    module InstanceMethods
      def create_with_locale!(method_name, *parameters)
        original_locale = I18n.locale
        begin
          create_without_locale!(method_name, *parameters)
        ensure
          I18n.locale = original_locale
        end
      end
    end
  end

  ActionMailer::Base.send(:include, I18nActionMailer)

and then in your mailer class start your method by setting the desired locale, for example:

  def welcome(user)
    I18n.locale = user.locale
    # etc.
  end

Answer 4

This simple plugin was developed for rails 2 but seems to work in rails 3 too.

http://github.com/Bertg/i18n_action_mailer

With it you can do the following:

def new_follower(user, follower)
  @follower = follower
  @user = user
  set_locale user.locale
  mail :to => @user.email, :subject => t(:new_follower_subject)
end

The subject and mail templates are then translated using the user's locale.

Answer 5

I believe the best way to do this is with the great method I18n.with_locale, it allows you to temporarily change the I18n.locale inside a block, you can use it like this:

def new_follower(user, follower)
  @follower = follower
  @user = user
  I18n.with_locale(@user.profile.locale) do
    mail to: @user.email
  end
end

And it'll change the locale just to send the email, immediately changing back after the block ends.

Source: http://www.rubydoc.info/docs/rails/2.3.8/I18n.with_locale

Answer 6

This answer was a dirty hack that ignored I18n's with_locale method, which is in another answer. The original answer (which works but you shouldn't use it) is below.

Quick and dirty:

class SystemMailer < ActionMailer::Base
  def new_follower(user, follower)
    @follower = follower
    @user = user
    using_locale(@user.profile.locale){mail(:to=>@user.email)}
  end

  protected
  def using_locale(locale, &block)
    original_locale = I18n.locale
    I18n.locale = locale
    return_value = yield
    I18n.locale = original_locale
    return_value
  end
end