Add feature flag for QueryPhaseSearcher

build.gradle

@@ -253,6 +253,8 @@ testClusters.integTest {
     // Increase heap size from default of 512mb to 1gb. When heap size is 512mb, our integ tests sporadically fail due
     // to ml-commons memory circuit breaker exception
     jvmArgs("-Xms1g", "-Xmx1g")
+    // enable hybrid search for testing
+    systemProperty('neural_search_hybrid_search_enabled', 'true')
 }
 
 // Remote Integration Tests

src/main/java/org/opensearch/neuralsearch/plugin/NeuralSearch.java

@@ -16,7 +16,8 @@
 import org.opensearch.client.Client;
 import org.opensearch.cluster.metadata.IndexNameExpressionResolver;
 import org.opensearch.cluster.service.ClusterService;
-import org.opensearch.common.io.stream.NamedWriteableRegistry;
+import org.opensearch.common.util.FeatureFlags;
+import org.opensearch.core.common.io.stream.NamedWriteableRegistry;
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.env.Environment;
 import org.opensearch.env.NodeEnvironment;
@@ -39,11 +40,19 @@
 import org.opensearch.threadpool.ThreadPool;
 import org.opensearch.watcher.ResourceWatcherService;
 
+import com.google.common.annotations.VisibleForTesting;
+
 /**
  * Neural Search plugin class
  */
 public class NeuralSearch extends Plugin implements ActionPlugin, SearchPlugin, IngestPlugin, ExtensiblePlugin {
-
+    /**
+     * Gates the functionality of hybrid search
+     * Currently query phase searcher added with hybrid search will conflict with concurrent search in core.
+     * Once that problem is resolved this feature flag can be removed.
+     */
+    @VisibleForTesting
+    public static final String NEURAL_SEARCH_HYBRID_SEARCH_ENABLED = "neural_search_hybrid_search_enabled";
     private MLCommonsClientAccessor clientAccessor;
 
     @Override
@@ -80,6 +89,10 @@ public Map<String, Processor.Factory> getProcessors(Processor.Parameters paramet
 
     @Override
     public Optional<QueryPhaseSearcher> getQueryPhaseSearcher() {
-        return Optional.of(new HybridQueryPhaseSearcher());
+        if (FeatureFlags.isEnabled(NEURAL_SEARCH_HYBRID_SEARCH_ENABLED)) {
+            return Optional.of(new HybridQueryPhaseSearcher());
+        }
+        // we want feature be disabled by default due to risk of colliding and breaking concurrent search in core
+        return Optional.empty();
     }
 }

src/main/java/org/opensearch/neuralsearch/query/HybridQueryBuilder.java

@@ -21,11 +21,11 @@
 
 import org.apache.commons.lang.builder.EqualsBuilder;
 import org.apache.lucene.search.Query;
-import org.opensearch.common.ParsingException;
-import org.opensearch.common.io.stream.StreamInput;
-import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.common.lucene.search.Queries;
 import org.opensearch.core.ParseField;
+import org.opensearch.core.common.ParsingException;
+import org.opensearch.core.common.io.stream.StreamInput;
+import org.opensearch.core.common.io.stream.StreamOutput;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.core.xcontent.XContentParser;
 import org.opensearch.index.query.AbstractQueryBuilder;

src/main/java/org/opensearch/neuralsearch/query/NeuralQueryBuilder.java

@@ -23,11 +23,11 @@
 import org.apache.commons.lang.builder.HashCodeBuilder;
 import org.apache.lucene.search.Query;
 import org.opensearch.action.ActionListener;
-import org.opensearch.common.ParsingException;
 import org.opensearch.common.SetOnce;
-import org.opensearch.common.io.stream.StreamInput;
-import org.opensearch.common.io.stream.StreamOutput;
 import org.opensearch.core.ParseField;
+import org.opensearch.core.common.ParsingException;
+import org.opensearch.core.common.io.stream.StreamInput;
+import org.opensearch.core.common.io.stream.StreamOutput;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.core.xcontent.XContentParser;
 import org.opensearch.index.mapper.NumberFieldMapper;

src/test/java/org/opensearch/neuralsearch/TestUtils.java

@@ -9,8 +9,8 @@
 
 import java.util.Map;
 
-import org.opensearch.common.bytes.BytesReference;
 import org.opensearch.common.xcontent.XContentHelper;
+import org.opensearch.core.common.bytes.BytesReference;
 import org.opensearch.core.xcontent.XContentBuilder;
 
 public class TestUtils {

src/test/java/org/opensearch/neuralsearch/common/BaseNeuralSearchIT.java

@@ -40,12 +40,12 @@
 import org.opensearch.common.xcontent.XContentFactory;
 import org.opensearch.common.xcontent.XContentHelper;
 import org.opensearch.common.xcontent.XContentType;
+import org.opensearch.core.rest.RestStatus;
 import org.opensearch.core.xcontent.ToXContent;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.index.query.QueryBuilder;
 import org.opensearch.knn.index.SpaceType;
 import org.opensearch.neuralsearch.OpenSearchSecureRestTestCase;
-import org.opensearch.rest.RestStatus;
 
 import com.google.common.collect.ImmutableList;
 

src/test/java/org/opensearch/neuralsearch/plugin/NeuralSearchTests.java

@@ -15,12 +15,12 @@
 import org.opensearch.neuralsearch.processor.TextEmbeddingProcessor;
 import org.opensearch.neuralsearch.query.HybridQueryBuilder;
 import org.opensearch.neuralsearch.query.NeuralQueryBuilder;
+import org.opensearch.neuralsearch.query.OpenSearchQueryTestCase;
 import org.opensearch.neuralsearch.search.query.HybridQueryPhaseSearcher;
 import org.opensearch.plugins.SearchPlugin;
 import org.opensearch.search.query.QueryPhaseSearcher;
-import org.opensearch.test.OpenSearchTestCase;
 
-public class NeuralSearchTests extends OpenSearchTestCase {
+public class NeuralSearchTests extends OpenSearchQueryTestCase {
 
     public void testQuerySpecs() {
         NeuralSearch plugin = new NeuralSearch();
@@ -37,8 +37,15 @@ public void testQueryPhaseSearcher() {
         Optional<QueryPhaseSearcher> queryPhaseSearcher = plugin.getQueryPhaseSearcher();
 
         assertNotNull(queryPhaseSearcher);
-        assertFalse(queryPhaseSearcher.isEmpty());
-        assertTrue(queryPhaseSearcher.get() instanceof HybridQueryPhaseSearcher);
+        assertTrue(queryPhaseSearcher.isEmpty());
+
+        initFeatureFlags();
+
+        Optional<QueryPhaseSearcher> queryPhaseSearcherWithFeatureFlagDisabled = plugin.getQueryPhaseSearcher();
+
+        assertNotNull(queryPhaseSearcherWithFeatureFlagDisabled);
+        assertFalse(queryPhaseSearcherWithFeatureFlagDisabled.isEmpty());
+        assertTrue(queryPhaseSearcherWithFeatureFlagDisabled.get() instanceof HybridQueryPhaseSearcher);
     }
 
     public void testProcessors() {

src/test/java/org/opensearch/neuralsearch/query/HybridQueryBuilderTests.java

@@ -28,25 +28,26 @@
 import org.apache.lucene.search.MatchNoDocsQuery;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.TermQuery;
-import org.opensearch.common.ParsingException;
-import org.opensearch.common.bytes.BytesReference;
 import org.opensearch.common.io.stream.BytesStreamOutput;
-import org.opensearch.common.io.stream.FilterStreamInput;
-import org.opensearch.common.io.stream.NamedWriteableAwareStreamInput;
-import org.opensearch.common.io.stream.NamedWriteableRegistry;
 import org.opensearch.common.xcontent.XContentFactory;
 import org.opensearch.core.ParseField;
+import org.opensearch.core.common.ParsingException;
+import org.opensearch.core.common.bytes.BytesReference;
+import org.opensearch.core.common.io.stream.FilterStreamInput;
+import org.opensearch.core.common.io.stream.NamedWriteableAwareStreamInput;
+import org.opensearch.core.common.io.stream.NamedWriteableRegistry;
+import org.opensearch.core.index.Index;
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.core.xcontent.ToXContent;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.core.xcontent.XContentParser;
-import org.opensearch.index.Index;
 import org.opensearch.index.mapper.TextFieldMapper;
 import org.opensearch.index.query.MatchAllQueryBuilder;
 import org.opensearch.index.query.QueryBuilder;
 import org.opensearch.index.query.QueryBuilders;
 import org.opensearch.index.query.QueryShardContext;
 import org.opensearch.index.query.TermQueryBuilder;
+import org.opensearch.knn.index.VectorDataType;
 import org.opensearch.knn.index.mapper.KNNVectorFieldMapper;
 import org.opensearch.knn.index.query.KNNQuery;
 import org.opensearch.knn.index.query.KNNQueryBuilder;
@@ -82,6 +83,7 @@ public void testDoToQuery_whenOneSubquery_thenBuildSuccessfully() {
         KNNVectorFieldMapper.KNNVectorFieldType mockKNNVectorField = mock(KNNVectorFieldMapper.KNNVectorFieldType.class);
         when(mockQueryShardContext.index()).thenReturn(dummyIndex);
         when(mockKNNVectorField.getDimension()).thenReturn(4);
+        when(mockKNNVectorField.getVectorDataType()).thenReturn(VectorDataType.FLOAT);
         when(mockQueryShardContext.fieldMapper(eq(VECTOR_FIELD_NAME))).thenReturn(mockKNNVectorField);
 
         NeuralQueryBuilder neuralQueryBuilder = new NeuralQueryBuilder().fieldName(VECTOR_FIELD_NAME)
@@ -110,6 +112,7 @@ public void testDoToQuery_whenMultipleSubqueries_thenBuildSuccessfully() {
         KNNVectorFieldMapper.KNNVectorFieldType mockKNNVectorField = mock(KNNVectorFieldMapper.KNNVectorFieldType.class);
         when(mockQueryShardContext.index()).thenReturn(dummyIndex);
         when(mockKNNVectorField.getDimension()).thenReturn(4);
+        when(mockKNNVectorField.getVectorDataType()).thenReturn(VectorDataType.FLOAT);
         when(mockQueryShardContext.fieldMapper(eq(VECTOR_FIELD_NAME))).thenReturn(mockKNNVectorField);
 
         NeuralQueryBuilder neuralQueryBuilder = new NeuralQueryBuilder().fieldName(VECTOR_FIELD_NAME)

src/test/java/org/opensearch/neuralsearch/query/HybridQueryIT.java

@@ -138,7 +138,7 @@ public void testScoreCorrectness_whenHybridWithNeuralQuery_thenScoresAreCorrect(
             TEST_KNN_VECTOR_FIELD_NAME_1,
             TEST_QUERY_TEXT,
             modelId.get(),
-            1,
+            3,
             null,
             null
         );
@@ -150,7 +150,7 @@ public void testScoreCorrectness_whenHybridWithNeuralQuery_thenScoresAreCorrect(
 
         Map<String, Object> searchResponseAsMap = search(TEST_BASIC_VECTOR_DOC_FIELD_INDEX_NAME, hybridQueryBuilderNeuralThenTerm, 3);
 
-        assertEquals(2, getHitCount(searchResponseAsMap));
+        assertEquals(3, getHitCount(searchResponseAsMap));
 
         List<Map<String, Object>> hitsNestedList = getNestedHits(searchResponseAsMap);
         List<Double> scores = new ArrayList<>();

src/test/java/org/opensearch/neuralsearch/query/HybridQueryTests.java

@@ -34,7 +34,7 @@
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.tests.analysis.MockAnalyzer;
 import org.apache.lucene.tests.search.QueryUtils;
-import org.opensearch.index.Index;
+import org.opensearch.core.index.Index;
 import org.opensearch.index.mapper.TextFieldMapper;
 import org.opensearch.index.query.BoolQueryBuilder;
 import org.opensearch.index.query.QueryBuilders;

src/test/java/org/opensearch/neuralsearch/query/NeuralQueryBuilderTests.java

@@ -31,14 +31,14 @@
 
 import org.opensearch.action.ActionListener;
 import org.opensearch.client.Client;
-import org.opensearch.common.ParsingException;
-import org.opensearch.common.bytes.BytesReference;
 import org.opensearch.common.io.stream.BytesStreamOutput;
-import org.opensearch.common.io.stream.FilterStreamInput;
-import org.opensearch.common.io.stream.NamedWriteableAwareStreamInput;
-import org.opensearch.common.io.stream.NamedWriteableRegistry;
 import org.opensearch.common.xcontent.XContentFactory;
 import org.opensearch.core.ParseField;
+import org.opensearch.core.common.ParsingException;
+import org.opensearch.core.common.bytes.BytesReference;
+import org.opensearch.core.common.io.stream.FilterStreamInput;
+import org.opensearch.core.common.io.stream.NamedWriteableAwareStreamInput;
+import org.opensearch.core.common.io.stream.NamedWriteableRegistry;
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.core.xcontent.ToXContent;
 import org.opensearch.core.xcontent.XContentBuilder;

src/test/java/org/opensearch/neuralsearch/query/OpenSearchQueryTestCase.java

@@ -8,6 +8,7 @@
 import static java.util.Collections.emptyMap;
 import static java.util.Collections.singletonMap;
 import static java.util.stream.Collectors.toList;
+import static org.opensearch.neuralsearch.plugin.NeuralSearch.NEURAL_SEARCH_HYBRID_SEARCH_ENABLED;
 
 import java.io.IOException;
 import java.util.Arrays;
@@ -28,10 +29,11 @@
 import org.opensearch.Version;
 import org.opensearch.cluster.metadata.IndexMetadata;
 import org.opensearch.common.CheckedConsumer;
-import org.opensearch.common.bytes.BytesReference;
+import org.opensearch.common.SuppressForbidden;
 import org.opensearch.common.compress.CompressedXContent;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.common.xcontent.XContentFactory;
+import org.opensearch.core.common.bytes.BytesReference;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.analysis.AnalyzerScope;
@@ -222,4 +224,9 @@ public float getMaxScore(int upTo) {
             }
         };
     }
+
+    @SuppressForbidden(reason = "manipulates system properties for testing")
+    protected static void initFeatureFlags() {
+        System.setProperty(NEURAL_SEARCH_HYBRID_SEARCH_ENABLED, "true");
+    }
 }