Update test method

Signed-off-by: Vijayan Balasubramanian <[email protected]>

qa/restart-upgrade/src/test/java/org/opensearch/knn/bwc/IndexingIT.java

@@ -61,6 +61,23 @@ public void testKNNIndexDefaultLegacyFieldMapping() throws Exception {
         }
     }
 
+    // ensure that index is created using legacy mapping in old cluster, and, then, add docs to both old and new cluster.
+    // when search is requested on new cluster it should return all docs irrespective of cluster.
+    public void testKNNIndexDefaultEngine() throws Exception {
+        waitForClusterHealthGreen(NODES_BWC_CLUSTER);
+        if (isRunningAgainstOldCluster()) {
+            createKnnIndex(testIndex, getKNNDefaultIndexSettings(), createKnnIndexMapping(TEST_FIELD, DIMENSIONS));
+            addKNNDocs(testIndex, TEST_FIELD, DIMENSIONS, DOC_ID, 5);
+            // Flush to ensure that index is not re-indexed when node comes back up
+            flush(testIndex, true);
+        } else {
+            validateKNNSearch(testIndex, TEST_FIELD, DIMENSIONS, 5, 5);
+            addKNNDocs(testIndex, TEST_FIELD, DIMENSIONS, 5, 5);
+            validateKNNSearch(testIndex, TEST_FIELD, DIMENSIONS, 10, 10);
+            deleteKNNIndex(testIndex);
+        }
+    }
+
     // Ensure that when segments created with old mapping are forcemerged in new cluster, they
     // succeed
     public void testKNNIndexDefaultLegacyFieldMappingForceMerge() throws Exception {

src/main/java/org/opensearch/knn/index/mapper/KNNVectorFieldMapper.java

@@ -500,9 +500,7 @@ private void resolveKNNMethodComponents(
                     .build()
             );
 
-            // If the original parameters are from legacy, and it is created on or before 2_17_2 since default is changed to
-            // FAISS starting 2_18, which doesn't support accepting algo params from index settings
-            if (parserContext.indexVersionCreated().onOrBefore(Version.V_2_17_2) && builder.originalParameters.isLegacyMapping()) {
+            if (useKNNMethodContextFromLegacy(builder, parserContext)) {
                 // Then create KNNMethodContext to be used from the legacy index settings
                 builder.originalParameters.setResolvedKnnMethodContext(
                     createKNNMethodContextFromLegacy(parserContext.getSettings(), parserContext.indexVersionCreated(), resolvedSpaceType)
@@ -551,6 +549,12 @@ private void setEngine(final KNNMethodContext knnMethodContext, KNNEngine knnEng
         }
     }
 
+    static boolean useKNNMethodContextFromLegacy(Builder builder, Mapper.TypeParser.ParserContext parserContext) {
+        // If the original parameters are from legacy, and it is created on or before 2_17_2 since default is changed to
+        // FAISS starting 2_18, which doesn't support accepting algo params from index settings
+        return parserContext.indexVersionCreated().onOrBefore(Version.V_2_17_2) && builder.originalParameters.isLegacyMapping();
+    }
+
     // We store the version of the index with the mapper as different version of Opensearch has different default
     // values of KNN engine Algorithms hyperparameters.
     protected Version indexCreatedVersion;

src/main/java/org/opensearch/knn/index/query/KNNWeight.java

@@ -251,7 +251,7 @@ private Map<Integer, Float> doANNSearch(
             spaceType = modelMetadata.getSpaceType();
             vectorDataType = modelMetadata.getVectorDataType();
         } else {
-            String engineName = fieldInfo.attributes().getOrDefault(KNN_ENGINE, KNNEngine.NMSLIB.getName());
+            String engineName = fieldInfo.attributes().getOrDefault(KNN_ENGINE, KNNEngine.DEFAULT.getName());
             knnEngine = KNNEngine.getEngine(engineName);
             String spaceTypeName = fieldInfo.attributes().getOrDefault(SPACE_TYPE, SpaceType.L2.getValue());
             spaceType = SpaceType.getSpace(spaceTypeName);

src/test/java/org/opensearch/knn/index/engine/EngineResolverTests.java

@@ -41,10 +41,10 @@ public void testResolveEngine_whenModeAndCompressionAreFalse_thenDefault() {
         );
     }
 
-    public void testResolveEngine_whenModeSpecifiedAndCompressionIsNotSpecified_thenDefault() {
+    public void testResolveEngine_whenModeSpecifiedAndCompressionIsNotSpecified_thenNMSLIB() {
         assertEquals(KNNEngine.DEFAULT, ENGINE_RESOLVER.resolveEngine(KNNMethodConfigContext.builder().build(), null, false));
         assertEquals(
-            KNNEngine.DEFAULT,
+            KNNEngine.NMSLIB,
             ENGINE_RESOLVER.resolveEngine(
                 KNNMethodConfigContext.builder().mode(Mode.IN_MEMORY).build(),
                 new KNNMethodContext(KNNEngine.DEFAULT, SpaceType.UNDEFINED, MethodComponentContext.EMPTY, false),
@@ -63,7 +63,7 @@ public void testResolveEngine_whenCompressionIs1x_thenEngineBasedOnMode() {
             )
         );
         assertEquals(
-            KNNEngine.DEFAULT,
+            KNNEngine.NMSLIB,
             ENGINE_RESOLVER.resolveEngine(KNNMethodConfigContext.builder().compressionLevel(CompressionLevel.x1).build(), null, false)
         );
     }

src/test/java/org/opensearch/knn/index/mapper/KNNVectorFieldMapperTests.java

@@ -65,6 +65,7 @@
 import java.util.Optional;
 import java.util.stream.Collectors;
 
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
@@ -284,36 +285,43 @@ public void testTypeParser_withDifferentSpaceTypeCombinations_thenSuccess() thro
         );
         assertTrue(knnVectorFieldMapper.fieldType().getKnnMappingConfig().getModelId().isEmpty());
 
-        // if space type is provided and legacy mappings is hit
-        xContentBuilder = XContentFactory.jsonBuilder()
-            .startObject()
-            .field(TYPE_FIELD_NAME, KNN_VECTOR_TYPE)
-            .field(DIMENSION_FIELD_NAME, TEST_DIMENSION)
-            .field(KNNConstants.TOP_LEVEL_PARAMETER_SPACE_TYPE, topLevelSpaceType.getValue())
-            .endObject();
-        builder = (KNNVectorFieldMapper.Builder) typeParser.parse(
-            "test-field-name-1",
-            xContentBuilderToMap(xContentBuilder),
-            buildParserContext("test", settings)
-        );
+        // mock useKNNMethodContextFromLegacy to simulate index ix created before 2_18
+        try (MockedStatic<KNNVectorFieldMapper> utilMockedStatic = Mockito.mockStatic(KNNVectorFieldMapper.class)) {
+            utilMockedStatic.when(() -> KNNVectorFieldMapper.useKNNMethodContextFromLegacy(any(), any())).thenReturn(true);
+            // if space type is provided and legacy mappings is hit
+            xContentBuilder = XContentFactory.jsonBuilder()
+                .startObject()
+                .field(TYPE_FIELD_NAME, KNN_VECTOR_TYPE)
+                .field(DIMENSION_FIELD_NAME, TEST_DIMENSION)
+                .field(KNNConstants.TOP_LEVEL_PARAMETER_SPACE_TYPE, topLevelSpaceType.getValue())
+                .endObject();
+            builder = (KNNVectorFieldMapper.Builder) typeParser.parse(
+                "test-field-name-1",
+                xContentBuilderToMap(xContentBuilder),
+                buildParserContext("test", settings)
+            );
 
-        builderContext = new Mapper.BuilderContext(settings, new ContentPath());
-        knnVectorFieldMapper = builder.build(builderContext);
-        assertTrue(knnVectorFieldMapper instanceof MethodFieldMapper);
-        assertTrue(knnVectorFieldMapper.fieldType().getKnnMappingConfig().getKnnMethodContext().isPresent());
-        assertEquals(topLevelSpaceType, knnVectorFieldMapper.fieldType().getKnnMappingConfig().getKnnMethodContext().get().getSpaceType());
-        // this check ensures that legacy mapping is hit, as in legacy mapping we pick M from index settings
-        assertEquals(
-            mForSetting,
-            knnVectorFieldMapper.fieldType()
-                .getKnnMappingConfig()
-                .getKnnMethodContext()
-                .get()
-                .getMethodComponentContext()
-                .getParameters()
-                .get(METHOD_PARAMETER_M)
-        );
-        assertTrue(knnVectorFieldMapper.fieldType().getKnnMappingConfig().getModelId().isEmpty());
+            builderContext = new Mapper.BuilderContext(settings, new ContentPath());
+            knnVectorFieldMapper = builder.build(builderContext);
+            assertTrue(knnVectorFieldMapper instanceof MethodFieldMapper);
+            assertTrue(knnVectorFieldMapper.fieldType().getKnnMappingConfig().getKnnMethodContext().isPresent());
+            assertEquals(
+                topLevelSpaceType,
+                knnVectorFieldMapper.fieldType().getKnnMappingConfig().getKnnMethodContext().get().getSpaceType()
+            );
+            // this check ensures that legacy mapping is hit, as in legacy mapping we pick M from index settings
+            assertEquals(
+                mForSetting,
+                knnVectorFieldMapper.fieldType()
+                    .getKnnMappingConfig()
+                    .getKnnMethodContext()
+                    .get()
+                    .getMethodComponentContext()
+                    .getParameters()
+                    .get(METHOD_PARAMETER_M)
+            );
+            assertTrue(knnVectorFieldMapper.fieldType().getKnnMappingConfig().getModelId().isEmpty());
+        }
     }
 
     public void testTypeParser_withSpaceTypeAndMode_thenSuccess() throws IOException {
@@ -1703,7 +1711,7 @@ public void testTypeParser_whenModeAndCompressionAreSet_thenHandle() throws IOEx
         assertFalse(builder.getOriginalParameters().isLegacyMapping());
         validateBuilderAfterParsing(
             builder,
-            KNNEngine.DEFAULT,
+            KNNEngine.NMSLIB,
             SpaceType.L2,
             VectorDataType.FLOAT,
             CompressionLevel.x1,

src/test/java/org/opensearch/knn/index/query/KNNWeightTests.java

@@ -175,7 +175,11 @@ public void tearDownAfterTest() {
     @SneakyThrows
     public void testQueryResultScoreNmslib() {
         for (SpaceType space : List.of(SpaceType.L2, SpaceType.L1, SpaceType.COSINESIMIL, SpaceType.INNER_PRODUCT, SpaceType.LINF)) {
-            testQueryScore(space::scoreTranslation, SEGMENT_FILES_NMSLIB, Map.of(SPACE_TYPE, space.getValue()));
+            testQueryScore(
+                space::scoreTranslation,
+                SEGMENT_FILES_NMSLIB,
+                Map.of(SPACE_TYPE, space.getValue(), KNN_ENGINE, KNNEngine.NMSLIB.getName())
+            );
         }
     }