Adding List-Unsubscribe to header of newsletters

lib/Cron/Workers/SendingQueue/SendingQueue.php

@@ -5,9 +5,15 @@ use MailPoet\Cron\CronHelper;
 use MailPoet\Cron\Workers\SendingQueue\Tasks\Mailer as MailerTask;
 use MailPoet\Cron\Workers\SendingQueue\Tasks\Newsletter as NewsletterTask;
 use MailPoet\Mailer\MailerLog;
+use MailPoet\Models\NewsletterLink;
 use MailPoet\Models\SendingQueue as SendingQueueModel;
-use MailPoet\Models\Subscriber as SubscriberModel;
+use MailPoet\Models\Setting;
 use MailPoet\Models\StatisticsNewsletters as StatisticsNewslettersModel;
+use MailPoet\Models\Subscriber as SubscriberModel;
+use MailPoet\Newsletter\Links\Links;
+use MailPoet\Router\Endpoints\Track;
+use MailPoet\Router\Router;
+use MailPoet\Subscription\Url;
 
 if(!defined('ABSPATH')) exit;
 
@@ -116,7 +122,8 @@ class SendingQueue {
           $prepared_subscribers_ids,
           $prepared_newsletters[0],
           $prepared_subscribers[0],
-          $statistics
+          $statistics,
+          $this->getExtraParams($queue, $prepared_subscribers_ids)
         );
         $prepared_newsletters = array();
         $prepared_subscribers = array();
@@ -138,12 +145,13 @@ class SendingQueue {
 
   function sendNewsletters(
     $queue, $prepared_subscribers_ids, $prepared_newsletters,
-    $prepared_subscribers, $statistics
+    $prepared_subscribers, $statistics, $extra_params = array()
   ) {
     // send newsletter
     $send_result = $this->mailer_task->send(
       $prepared_newsletters,
-      $prepared_subscribers
+      $prepared_subscribers,
+      $extra_params
     );
     // log error message and schedule retry/pause sending
     if($send_result['response'] === false) {
@@ -172,6 +180,33 @@ class SendingQueue {
     MailerLog::enforceExecutionRequirements();
   }
 
+  protected function getExtraParams($queue, $prepared_subscribers_ids) {
+    $subscriber_id = $prepared_subscribers_ids[0];
+    $subscriber = SubscriberModel::where('id', $subscriber_id)->findOne();
+    
+    if((boolean)Setting::getValue('tracking.enabled')) {
+      $link_hash = NewsletterLink::where('queue_id', $queue->id)
+        ->where('url', '[link:subscription_unsubscribe_url]')
+        ->findOne()
+        ->hash;
+      $data = Links::createUrlDataObject(
+        $subscriber_id, 
+        $subscriber->email,
+        $queue->id, 
+        $link_hash, 
+        false
+      );
+      $url = Router::buildRequest(
+        Track::ENDPOINT,
+        Track::ACTION_CLICK,
+        $data
+      );
+    } else {
+      $url = Url::getUnsubscribeUrl($subscriber);
+    }
+    return array('unsubscribe_url' => $url);
+  }
+
   static function getRunningQueues() {
     return SendingQueueModel::orderByAsc('priority')
       ->whereNull('deleted_at')

lib/Cron/Workers/SendingQueue/Tasks/Mailer.php

@@ -3,6 +3,7 @@ namespace MailPoet\Cron\Workers\SendingQueue\Tasks;
 
 use MailPoet\Mailer\Mailer as MailerFactory;
 use MailPoet\Mailer\MailerLog;
+use MailPoet\Subscription\Url;
 
 if(!defined('ABSPATH')) exit;
 
@@ -54,10 +55,11 @@ class Mailer {
     return $this->mailer->formatSubscriberNameAndEmailAddress($subscriber);
   }
 
-  function send($prepared_newsletters, $prepared_subscribers) {
+  function send($prepared_newsletters, $prepared_subscribers, $extra_params = array()) {
     return $this->mailer->mailer_instance->send(
       $prepared_newsletters,
-      $prepared_subscribers
+      $prepared_subscribers,
+      $extra_params
     );
   }
 }

lib/Subscription/Url.php

@@ -33,6 +33,9 @@ class Url {
       if(is_object($subscriber)) {
         $subscriber = $subscriber->asArray();
       }
+      if(is_string($subscriber)) {
+        $subscriber = array('email' => $subscriber);
+      }
 
       $data = array(
         'token' => Subscriber::generateToken($subscriber['email']),