- Adds queue management and supervisor. Issue #227

lib/Queue/Supervisor.php

@@ -0,0 +1,48 @@
+<?php
+namespace MailPoet\Queue;
+
+use Carbon\Carbon;
+use MailPoet\Models\Setting;
+
+if(!defined('ABSPATH')) exit;
+
+class Supervisor {
+  function __construct() {
+    list ($this->queue, $this->queueData) = $this->getQueue();
+  }
+
+  function checkQueue() {
+    if(!$this->queue) {
+      $this->startQueue();
+    } else {
+      if($this->queueData['status'] !== 'paused' &&
+        $this->queueData['status'] !== 'stopped'
+      ) {
+        return;
+      }
+      $currentTime = Carbon::now('UTC');
+      $lastUpdateTime = Carbon::createFromFormat('Y-m-d H:i:s', $this->queue->updated_at, 'UTC');
+      $timeSinceLastStart = $currentTime->diffInSeconds($lastUpdateTime);
+      if($timeSinceLastStart < 50) return;
+      $this->queueData['status'] = 'paused';
+      $this->queue->value = serialize($this->queueData);
+      $this->queue->save();
+      $this->startQueue();
+    }
+  }
+
+  function startQueue() {
+    stream_context_set_default(array('http' => array('method' => 'HEAD')));
+    get_headers(home_url() . '/?mailpoet-api&section=queue&action=start', 1);
+  }
+
+  function getQueue() {
+    $queue = Setting::where('name', 'queue')
+      ->findOne();
+    $queueData = ($queue) ? unserialize($queue->value) : false;
+    return array(
+      $queue,
+      $queueData
+    );
+  }
+}