added boost field setter and getter for Knn Search

Author: hkulekci

src/Knn/Knn.php

@@ -39,7 +39,7 @@ class Knn implements BuilderInterface
     private $numCandidates;
 
     /**
-     * @var int
+     * @var float|null
      */
     private $boost;
 
@@ -153,6 +153,22 @@ public function setSimilarity(float $similarity): void
         $this->similarity = $similarity;
     }
 
+    /**
+     * @return float|null
+     */
+    public function getBoost(): ?float
+    {
+        return $this->boost;
+    }
+
+    /**
+     * @param float $boost
+     */
+    public function setBoost(float $boost): void
+    {
+        $this->boost = $boost;
+    }
+
     /**
      * @return BuilderInterface|null
      */
@@ -193,6 +209,10 @@ public function toArray()
             $output['similarity'] = $this->getSimilarity();
         }
 
+        if ($this->getBoost()) {
+            $output['boost'] = $this->getBoost();
+        }
+
         if ($this->getFilter()) {
             $output['filter'] = $this->getFilter()->toArray();
         }

tests/Functional/Knn/KnnTest.php

@@ -6,7 +6,8 @@
 
 namespace ONGR\ElasticsearchDSL\Tests\Functional\Knn;
 
-use ONGR\ElasticsearchDSL\Aggregation\Bucketing\DateHistogramAggregation;
+use Composer\InstalledVersions;
+use Elastic\Elasticsearch\Client;
 use ONGR\ElasticsearchDSL\Knn\Knn;
 use ONGR\ElasticsearchDSL\Query\TermLevel\TermQuery;
 use ONGR\ElasticsearchDSL\Search;
@@ -82,4 +83,24 @@ public function testKnnSearchWithFilter(): void
         $this->assertCount(1, $results['hits']['hits']);
         $this->assertEquals('doc_3', $results['hits']['hits'][0]['_id']);
     }
+
+    /**
+     * Match all test
+     */
+    public function testMultipleKnnSearchWithBoost(): void
+    {
+        $knn1 = new Knn('vector_field', [1, 2, 3], 1, 1);
+        $knn1->setFilter(new TermQuery('label', 2));
+        $knn1->setBoost(0.5);
+        $knn2 = new Knn('vector_field', [1, 2, 4], 1, 1);
+        $knn2->setFilter(new TermQuery('label', 2));
+        $knn2->setBoost(0.1);
+
+        $search = new Search();
+        $search->addKnn($knn1);
+        $search->addKnn($knn2);
+        $results = $this->executeSearch($search, true);
+        $this->assertCount(1, $results['hits']['hits']);
+        $this->assertEquals('doc_3', $results['hits']['hits'][0]['_id']);
+    }
 }