Rotate scheduled tasks

Scheduled tasks should rotate so that they don't block
sending when they cannot be send.

[MAILPOET-1391]

lib/Cron/Workers/Scheduler.php

@@ -5,6 +5,7 @@ namespace MailPoet\Cron\Workers;
 use Carbon\Carbon;
 use MailPoet\Cron\CronHelper;
 use MailPoet\Models\Newsletter;
+use MailPoet\Models\ScheduledTask;
 use MailPoet\Models\Subscriber;
 use MailPoet\Models\SubscriberSegment;
 use MailPoet\Segments\SubscribersFinder;
@@ -29,6 +30,7 @@ class Scheduler {
   function process() {
     $scheduled_queues = self::getScheduledQueues();
     if(!count($scheduled_queues)) return false;
+    $this->updateTasks($scheduled_queues);
     foreach($scheduled_queues as $i => $queue) {
       $newsletter = Newsletter::filter('filterWithOptions')
         ->findOne($queue->newsletter_id);
@@ -177,6 +179,13 @@ class Scheduler {
       false;
   }
 
+  private function updateTasks(array $scheduled_queues) {
+    $ids = array_map(function ($queue) {
+      return $queue->task_id;
+    }, $scheduled_queues);
+    ScheduledTask::touchAllByIds($ids);
+  }
+
   static function getScheduledQueues() {
     return SendingTask::getScheduledQueues(self::TASK_BATCH_SIZE);
   }

lib/Models/ScheduledTask.php

@@ -74,4 +74,12 @@ class ScheduledTask extends Model {
     parent::save();
     return $this;
   }
+
+  static function touchAllByIds(array $ids) {
+    ScheduledTask::rawExecute(
+      'UPDATE `' . ScheduledTask::$_table . '`' .
+      'SET `updated_at` = NOW() ' .
+      'WHERE `id` IN (' . join(',', $ids) . ')'
+    );
+  }
 }

lib/Tasks/Sending.php

@@ -227,6 +227,7 @@ class Sending {
       ->whereLte('scheduled_at', Carbon::createFromTimestamp(WPFunctions::currentTime('timestamp')))
       ->where('type', 'sending')
       ->whereNotEqual('status', ScheduledTask::STATUS_PAUSED)
+      ->orderByAsc('updated_at')
       ->limit($amount)
       ->findMany();
     $result = array();

tests/unit/Cron/Workers/SchedulerTest.php

@@ -571,6 +571,20 @@ class SchedulerTest extends \MailPoetTest {
     $scheduler->process();
   }
 
+  function testItUpdatesUpdateTime() {
+    $originalUpdated = Carbon::createFromTimestamp(current_time('timestamp'))->subHours(5)->toDateTimeString();
+    $newsletter = $this->_createNewsletter(Newsletter::TYPE_WELCOME, Newsletter::STATUS_DRAFT);
+    $queue = $this->_createQueue($newsletter->id);
+    $queue->scheduled_at = Carbon::createFromTimestamp(current_time('timestamp'));
+    $queue->updated_at = $originalUpdated;
+    $queue->save();
+    $scheduler = new Scheduler();
+    $scheduler->timer = microtime(true);
+    $scheduler->process();
+    $newQueue = ScheduledTask::findOne($queue->task_id);
+    expect($newQueue->updated_at)->notEquals($originalUpdated);
+  }
+
   function _createNewsletterSegment($newsletter_id, $segment_id) {
     $newsletter_segment = NewsletterSegment::create();
     $newsletter_segment->newsletter_id = $newsletter_id;
@@ -685,4 +699,4 @@ class SchedulerTest extends \MailPoetTest {
     \ORM::raw_execute('TRUNCATE ' . Segment::$_table);
     \ORM::raw_execute('TRUNCATE ' . NewsletterSegment::$_table);
   }
-}
+}

tests/unit/Tasks/SendingTest.php

@@ -176,6 +176,25 @@ class SendingTest extends \MailPoetTest {
     expect(SendingTask::getRunningQueues($amount))->count($amount);
   }
 
+  function testItGetsBatchOfRunningQueuesSortedByUpdatedTime() {
+    $this->_after();
+
+    $sending1 = $this->createNewSendingTask(['status' => ScheduledTask::STATUS_SCHEDULED]);
+    $sending1->updated_at = '2017-05-04 14:00:00';
+    $sending1->save();
+    $sending2 = $this->createNewSendingTask(['status' => ScheduledTask::STATUS_SCHEDULED]);
+    $sending2->updated_at = '2017-05-04 16:00:00';
+    $sending2->save();
+    $sending3 = $this->createNewSendingTask(['status' => ScheduledTask::STATUS_SCHEDULED]);
+    $sending3->updated_at = '2017-05-04 15:00:00';
+    $sending3->save();
+
+    $queues = SendingTask::getScheduledQueues(3);
+    expect($queues[0]->task_id)->equals($sending1->id());
+    expect($queues[1]->task_id)->equals($sending3->id());
+    expect($queues[2]->task_id)->equals($sending2->id());
+  }
+
   function createNewNewsletter() {
     $newsletter = Newsletter::create();
     $newsletter->type = Newsletter::TYPE_STANDARD;