Issue #1833578: Add support Enhanced Link Attribution

googleanalytics.admin.inc

@@ -201,6 +201,12 @@ function googleanalytics_admin_settings_form($form_state) {
     '#description' => t('A file extension list separated by the | character that will be tracked as download when clicked. Regular expressions are supported. For example: !extensions', array('!extensions' => GOOGLEANALYTICS_TRACKFILES_EXTENSIONS)),
     '#maxlength' => 255,
   );
+  $form['tracking']['linktracking']['googleanalytics_tracklinkid'] = array(
+    '#type' => 'checkbox',
+    '#title' => t('Enable enhanced link attribution'),
+    '#default_value' => variable_get('googleanalytics_tracklinkid', 0),
+    '#description' => t('Enhancements: separate click tracking for multiple links on a page with the same destination, better tracking for search buttons, and tracking for javascript links/buttons. To use this you must enable <a href="@url">enhanced link attribution</a> for this site on your Google Analytics account.', array('@url' => url('http://support.google.com/analytics/bin/answer.py', array('query' => array('answer' => '2558867'))))),
+  );
 
   // Message specific configurations.
   $form['tracking']['messagetracking'] = array(

googleanalytics.install

@@ -41,6 +41,7 @@ function googleanalytics_uninstall() {
   variable_del('googleanalytics_tracker_anonymizeip');
   variable_del('googleanalytics_trackfiles');
   variable_del('googleanalytics_trackfiles_extensions');
+  variable_del('googleanalytics_tracklinkid');
   variable_del('googleanalytics_trackmailto');
   variable_del('googleanalytics_trackmessages');
   variable_del('googleanalytics_trackoutbound');

googleanalytics.module

@@ -259,6 +259,12 @@ function googleanalytics_page_alter(&$page) {
       $script .= 'ga("set", "anonymizeIp", 1);';
     }
 
+    // Add enhanced link attribution after 'create', but before 'pageview' send.
+    // @see https://support.google.com/analytics/answer/2558867
+    if (variable_get('googleanalytics_tracklinkid', 0)) {
+      $script .= 'ga("require", "linkid", "linkid.js");';
+    }
+
     // Prepare Adsense tracking.
     $googleanalytics_adsense_script = 'window.google_analytics_uacct = ' . drupal_json_encode($id) . ';';