Adding param `track_total_hits` (#273)

src/Search.php

@@ -34,6 +34,14 @@ use ONGR\ElasticsearchDSL\SearchEndpoint\SuggestEndpoint;
  */
 class Search
 {
+    /**
+     * If you don’t need to track the total number of hits at all you can improve
+     * query times by setting this option to false. Defaults to true.
+     *
+     * @var bool
+     */
+    private $trackTotalHits;
+
     /**
      * To retrieve hits from a certain offset. Defaults to 0.
      *
@@ -447,6 +455,24 @@ class Search
         return $this;
     }
 
+    /**
+     * @return bool
+     */
+    public function isTrackTotalHits()
+    {
+        return $this->trackTotalHits;
+    }
+
+    /**
+     * @param bool $trackTotalHits
+     * @return $this
+     */
+    public function setTrackTotalHits(bool $trackTotalHits)
+    {
+        $this->trackTotalHits = $trackTotalHits;
+        return $this;
+    }
+
     /**
      * @return int
      */
@@ -719,6 +745,7 @@ class Search
             'indicesBoost' => 'indices_boost',
             'minScore' => 'min_score',
             'searchAfter' => 'search_after',
+            'trackTotalHits' => 'track_total_hits',
         ];
 
         foreach ($params as $field => $param) {