Add support for elasticsearch suggestions

close #4505

extensions/elasticsearch/CHANGELOG.md

@@ -12,7 +12,7 @@ Yii Framework 2 elasticsearch extension Change Log
 - Enh #4086: changedAttributes of afterSave Event now contain old values (dizews)
 - Enh: Make error messages more readable in HTML output (cebe)
 - Enh: Added support for query stats (cebe)
-- Enh: Added support for query suggesters (cebe)
+- Enh: Added support for query suggesters (cebe, tvdavid)
 - Chg #4451: Removed support for facets and replaced them with aggregations (cebe, tadaszelvys)
 - Chg: asArray in ActiveQuery is now equal to using the normal Query. This means, that the output structure has changed and `with` is supported anymore. (cebe)
 - Chg: Deletion of a record is now also considered successful if the record did not exist. (cebe)

extensions/elasticsearch/Command.php

@@ -38,15 +38,11 @@ class Command extends Component
      * @var array list of arrays or json strings that become parts of a query
      */
     public $queryParts;
-    /**
-     * @var array list of arrays to highlight search results on one or more fields
-     * @see http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-request-highlighting.html
-     */
-    public $highlight;
     public $options = [];
 
 
     /**
+     * Sends a request to the _search API and returns the result
      * @param array $options
      * @return mixed
      */
@@ -69,6 +65,29 @@ class Command extends Component
     }
 
     /**
+     * Sends a request to the _suggest API and returns the result
+     * @param string|array $suggester the suggester body
+     * @param array $options
+     * @return mixed
+     * @see http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/search-suggesters.html
+     */
+    public function suggest($suggester, $options = [])
+    {
+        if (empty($suggester)) {
+            $suggester = '{}';
+        }
+        if (is_array($suggester)) {
+            $suggester = Json::encode($suggester);
+        }
+        $url = [
+            $this->index !== null ? $this->index : '_all',
+            '_suggest'
+        ];
+
+        return $this->db->post($url, array_merge($this->options, $options), $suggester);
+    }
+
+    /**
      * Inserts a document into an index
      * @param string $index
      * @param string $type