Symfony2 Newsletter Manager

NewsletterManager.php

<?php

namespace Acme\Bundle\NewsletterBundle\Manager;

use Symfony\Component\HttpFoundation\Session\Session;

class NewsletterManager
{
   /**
    * @var \Swift_Mailer
    */
   private $mailer;

   /**
    * @var array
    */
   private $recipients;

   /**
    * @var Session
    */
   private $session;

   /**
    * @var string
    */
   private $mailFrom;

   /**
    * @param \Swift_Mailer $mailer
    */
   public function __construct(\Swift_Mailer $mailer, Session $session)
   {
       $this->mailer = $mailer;
       $this->session = $session;

       // load recipients
       $this->recipients = [];
       if ($session->has('newsletter_recipients')) {
           $this->recipients = $session->get('newsletter_recipients');
       }

       // this should actually be set in config
       $this->mailFrom = 'you@example.com';
   }

   /**
    * Subscribes a recipient for newsletter.
    *
    * @param string $emailAddress
    *
    * @return bool
    */
   public function subscribe($emailAddress)
   {
       if (array_search($emailAddress, $this->recipients) === false) {
           $this->recipients[] = $emailAddress;
           $this->session->set('newsletter_recipients', $this->recipients);

           return true;
       }

       return false;
   }

   /**
    * Unsubscribes recipient from newsletter.
    *
    * @param string $emailAddress
    *
    * @return bool
    */
   public function unsubscribe($emailAddress)
   {
       $index = array_search($emailAddress, $this->recipients);
       if ($index !== false) {
           unset($this->recipients[$index]);
           $this->session->set('newsletter_recipients', $this->recipients);

           return true;
       }

       return false;
   }

   /**
    * Sends a newsletter message to all registered recipients.
    *
    * @param string $subjectString
    * @param string $messageString
    */
   public function sendNewsletter($subjectString, $messageString)
   {
       // send mail to each subscribed email
       foreach ($this->getRecipients() as $recipient) {
           $message = new \Swift_Message($subjectString, $messageString);
           $message->setFrom($this->mailFrom);
           $message->setTo($recipient);
           $this->mailer->send($message);
       }
   }

   /**
    * Return all recipients of a newsletter.
    *
    * @return array
    */
   private function getRecipients()
   {
       return $this->recipients;
   }
}