Add drush command to rebuild the tracker for dkan search (#321)

modules/custom/dkan_search/drush.services.yml

@@ -0,0 +1,5 @@
+services:
+  dkan_search:commands:
+    class: \Drupal\dkan_search\Drush\DkanSearchCommands
+    tags:
+      - { name: drush.command }

modules/custom/dkan_search/src/Drush/DkanSearchCommands.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Drupal\dkan_search\Drush;
+
+use Drush\Commands\DrushCommands;
+use Drupal\search_api\Entity\Index;
+
+/**
+ * Class DkanSearchCommands.
+ *
+ * @package Drupal\dkan_search\Drush
+ */
+class DkanSearchCommands extends DrushCommands {
+
+  /**
+   * Rebuild the search api tracker for the dkan index.
+   *
+   * @command dkan-search:rebuild-tracker
+   */
+  public function rebuildTracker() {
+    $index = Index::load('dkan');
+    $index->rebuildTracker();
+  }
+
+}