Update PHPMailer and extend it to add some functionalities.

applications/dashboard/models/class.activitymodel.php

@@ -888,7 +888,7 @@ public function sendNotification($ActivityID, $Story = '', $Force = false) {
                         $Emailed = self::SENT_SKIPPED;
                     }
                 } catch (phpmailerException $pex) {
-                    if ($pex->getCode() == PHPMailer::STOP_CRITICAL) {
+                    if ($pex->getCode() == PHPMailer::STOP_CRITICAL && !$Email->PhpMailer->isServerError($pex)) {
                         $Emailed = self::SENT_FAIL;
                     } else {
                         $Emailed = self::SENT_ERROR;
@@ -1022,7 +1022,7 @@ public function email(&$Activity, $NoDelete = false) {
                 }
             }
         } catch (phpmailerException $pex) {
-            if ($pex->getCode() == PHPMailer::STOP_CRITICAL) {
+            if ($pex->getCode() == PHPMailer::STOP_CRITICAL && !$Email->PhpMailer->isServerError($pex)) {
                 $Emailed = self::SENT_FAIL;
             } else {
                 $Emailed = self::SENT_ERROR;
@@ -1163,7 +1163,7 @@ public function sendNotificationQueue() {
                             $Emailed = self::SENT_SKIPPED;
                         }
                     } catch (phpmailerException $pex) {
-                        if ($pex->getCode() == PHPMailer::STOP_CRITICAL) {
+                        if ($pex->getCode() == PHPMailer::STOP_CRITICAL && !$Email->PhpMailer->isServerError($pex)) {
                             $Emailed = self::SENT_FAIL;
                         } else {
                             $Emailed = self::SENT_ERROR;

composer.json

@@ -32,9 +32,10 @@
         "vanilla/htmlawed": "~2.0",
         "vanilla/nbbc": "~2.1",
         "vanilla/garden-password": "~1.0",
-		"tburry/pquery": "~1.1",
-		"container-interop/container-interop": "^1.1",
-        "vanilla/php-ico": "~1.0"
+        "vanilla/php-ico": "~1.0",
+        "tburry/pquery": "~1.1",
+        "phpmailer/phpmailer": "~5.2",
+        "container-interop/container-interop": "^1.1"
     },
     "autoload": {
         "classmap": [

library/Vanilla/VanillaMailer.php

@@ -0,0 +1,84 @@
+<?php
+/**
+ * @author Alexandre (DaazKu) Chouinard <alexandre.c@vanillaforums.com>
+ * @copyright 2009-2016 Vanilla Forums Inc.
+ * @license GPLv2
+ */
+
+namespace Vanilla;
+
+
+use Vanilla\Utility\CamelCaseScheme;
+
+/**
+ * Shim class used for backward compatibility.
+ */
+class VanillaMailer extends \PHPMailer {
+
+    /**
+     * Either set or get the value of "throwExceptions".
+     *
+     * @param bool $newValue Whether this instance should throw exceptions or not
+     * @return The current value
+     */
+    public function throwExceptions($newValue = null) {
+        deprecated('throwExceptions', 'getThrowExceptions/setThrowExceptions');
+        if ($newValue !== null) {
+            $this->exceptions = $newValue;
+        }
+        return $this->exceptions;
+    }
+
+    /**
+     * Get throwExceptions value.
+     *
+     * @return bool Is this instance set to throw exceptions or not.
+     */
+    public function getThrowExceptions() {
+        return $this->exceptions;
+    }
+
+    /**
+     * Set throwExceptions value.
+     *
+     * @param bool $newValue The new value to set.
+     * @return VanillaMailer
+     */
+    public function setThrowExceptions($newValue) {
+        $this->exceptions = (bool)$newValue;
+
+        return $this;
+    }
+
+    /**
+     * Return the number of recipients.
+     *
+     * @return int
+     */
+    public function countRecipients() {
+        deprecated('countRecipients', 'count($phpMailer->getAllRecipientAddresses())');
+        return count($this->getAllRecipientAddresses());
+    }
+
+    /**
+     * Check the phpmailerException message and tell us if the exception should be treated as
+     * a server error instead of a "critical" error.
+     * Server error means that we can try to resend the email.
+     */
+    public function isServerError(\phpmailerException $e) {
+        $serverErrorMessages = [
+            'connect_host',
+            'data_not_accepted',
+            'smtp_connect_failed',
+            'execute',
+        ];
+
+        foreach($serverErrorMessages as $errorMessage) {
+           if (strpos($e->getMessage(), $this->lang($errorMessage)) !== false) {
+               return true;
+           }
+        }
+
+        return false;
+    }
+}

library/core/class.email.php

@@ -41,10 +41,9 @@ class Gdn_Email extends Gdn_Pluggable {
      * Constructor.
      */
     function __construct() {
-        $this->PhpMailer = new PHPMailer();
-        $this->PhpMailer->CharSet = c('Garden.Charset', 'utf-8');
+        $this->PhpMailer = new \Vanilla\VanillaMailer();
+        $this->PhpMailer->CharSet = 'utf-8';
         $this->PhpMailer->SingleTo = c('Garden.Email.SingleTo', false);
-        $this->PhpMailer->PluginDir = combinePaths(array(PATH_LIBRARY, 'vendors/phpmailer/'));
         $this->PhpMailer->Hostname = c('Garden.Email.Hostname', '');
         $this->PhpMailer->Encoding = 'quoted-printable';
         $this->clear();
@@ -353,12 +352,12 @@ public function send($EventName = '') {
             $this->fireEvent('SendMail');
         }
 
-        if (!empty($this->Skipped) && $this->PhpMailer->countRecipients() == 0) {
+        if (!empty($this->Skipped) && count($this->PhpMailer->getAllRecipientAddresses()) == 0) {
             // We've skipped all recipients.
             throw new Exception('No valid email recipients.', self::ERR_SKIPPED);
         }
 
-        $this->PhpMailer->throwExceptions(true);
+        $this->PhpMailer->setThrowExceptions(true);
         if (!$this->PhpMailer->send()) {
             throw new Exception($this->PhpMailer->ErrorInfo);
         }