agenda-libre-ruby/app/mailers/event_mailer.rb

class EventMailer < ActionMailer::Base
  default from: 'moderateurs@agendadulibre.org'

  def create(event)
    @event = event

    mail 'Message-ID' => "<event-#{event.id}@#{ActionMailer::Base.default_url_options[:host]}>",
      to: event.contact,
      subject: t('event_mailer.create.subject', subject: event.title)
  end
end