Revert "refactor(semantic_text): fail early in pre-8.11 indices (elastic#133080)"

This reverts commit 8f41a4b.

Author: Mikep86

server/src/test/java/org/elasticsearch/index/mapper/vectors/DenseVectorFieldMapperTests.java

@@ -67,7 +67,6 @@
 import static org.apache.lucene.tests.index.BaseKnnVectorsFormatTestCase.randomNormalizedVector;
 import static org.elasticsearch.index.codec.vectors.diskbbq.ES920DiskBBQVectorsFormat.DYNAMIC_VISIT_RATIO;
 import static org.elasticsearch.index.mapper.vectors.DenseVectorFieldMapper.DEFAULT_OVERSAMPLE;
-import static org.elasticsearch.index.mapper.vectors.DenseVectorFieldMapper.INDEXED_BY_DEFAULT_INDEX_VERSION;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.instanceOf;
@@ -106,7 +105,7 @@ private void indexMapping(XContentBuilder b, IndexVersion indexVersion) throws I
         if (elementType != ElementType.FLOAT) {
             b.field("element_type", elementType.toString());
         }
-        if (indexVersion.onOrAfter(INDEXED_BY_DEFAULT_INDEX_VERSION) || indexed) {
+        if (indexVersion.onOrAfter(DenseVectorFieldMapper.INDEXED_BY_DEFAULT_INDEX_VERSION) || indexed) {
             // Serialize if it's new index version, or it was not the default for previous indices
             b.field("index", indexed);
         }

x-pack/plugin/inference/src/main/java/org/elasticsearch/xpack/inference/mapper/SemanticTextFieldMapper.java

@@ -100,7 +100,6 @@
 import java.util.function.Function;
 import java.util.function.Supplier;
 
-import static org.elasticsearch.index.IndexVersions.NEW_SPARSE_VECTOR;
 import static org.elasticsearch.index.IndexVersions.SEMANTIC_TEXT_DEFAULTS_TO_BBQ;
 import static org.elasticsearch.index.IndexVersions.SEMANTIC_TEXT_DEFAULTS_TO_BBQ_BACKPORT_8_X;
 import static org.elasticsearch.inference.TaskType.SPARSE_EMBEDDING;
@@ -127,7 +126,6 @@
  */
 public class SemanticTextFieldMapper extends FieldMapper implements InferenceFieldMapper {
     private static final Logger logger = LogManager.getLogger(SemanticTextFieldMapper.class);
-    public static final String UNSUPPORTED_INDEX_MESSAGE = "[semantic_text] is available on indices created with 8.11 or higher.";
     public static final NodeFeature SEMANTIC_TEXT_IN_OBJECT_FIELD_FIX = new NodeFeature("semantic_text.in_object_field_fix");
     public static final NodeFeature SEMANTIC_TEXT_SINGLE_FIELD_UPDATE_FIX = new NodeFeature("semantic_text.single_field_update_fix");
     public static final NodeFeature SEMANTIC_TEXT_DELETE_FIX = new NodeFeature("semantic_text.delete_fix");
@@ -166,9 +164,6 @@ public static final TypeParser parser(Supplier<ModelRegistry> modelRegistry) {
 
     public static BiConsumer<String, MappingParserContext> validateParserContext(String type) {
         return (n, c) -> {
-            if (c.getIndexSettings().getIndexVersionCreated().before(NEW_SPARSE_VECTOR)) {
-                throw new UnsupportedOperationException(UNSUPPORTED_INDEX_MESSAGE);
-            }
             if (InferenceMetadataFieldsMapper.isEnabled(c.getIndexSettings().getSettings()) == false) {
                 notInMultiFields(type).accept(n, c);
             }

x-pack/plugin/inference/src/test/java/org/elasticsearch/xpack/inference/mapper/SemanticTextFieldMapperTests.java

@@ -111,7 +111,6 @@
 import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldMapper.DEFAULT_ELSER_2_INFERENCE_ID;
 import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldMapper.DEFAULT_RESCORE_OVERSAMPLE;
 import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldMapper.INDEX_OPTIONS_FIELD;
-import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldMapper.UNSUPPORTED_INDEX_MESSAGE;
 import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldTests.generateRandomChunkingSettings;
 import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldTests.generateRandomChunkingSettingsOtherThan;
 import static org.elasticsearch.xpack.inference.mapper.SemanticTextFieldTests.randomSemanticText;
@@ -415,57 +414,6 @@ public void testInvalidTaskTypes() {
         }
     }
 
-    @Override
-    protected IndexVersion boostNotAllowedIndexVersion() {
-        return IndexVersions.NEW_SPARSE_VECTOR;
-    }
-
-    public void testOldIndexSemanticTextDenseVectorRaisesError() throws IOException {
-        final String fieldName = "field";
-        final XContentBuilder fieldMapping = fieldMapping(b -> {
-            b.field("type", "semantic_text");
-            b.field(INFERENCE_ID_FIELD, "test_inference_id");
-            b.startObject("model_settings");
-            b.field("task_type", "text_embedding");
-            b.field("dimensions", 384);
-            b.field("similarity", "cosine");
-            b.field("element_type", "float");
-            b.endObject();
-        });
-        assertOldIndexUnsupported(fieldMapping);
-    }
-
-    public void testOldIndexSemanticTextMinimalMappingRaisesError() throws IOException {
-        final XContentBuilder fieldMapping = fieldMapping(this::minimalMapping);
-        assertOldIndexUnsupported(fieldMapping);
-    }
-
-    public void testOldIndexSemanticTextSparseVersionRaisesError() throws IOException {
-        final XContentBuilder fieldMapping = fieldMapping(b -> {
-            b.field("type", "semantic_text");
-            b.field("inference_id", "another_inference_id");
-            b.startObject("model_settings");
-            b.field("task_type", "sparse_embedding");
-            b.endObject();
-        });
-        assertOldIndexUnsupported(fieldMapping);
-    }
-
-    private void assertOldIndexUnsupported(XContentBuilder fieldMapping) {
-
-        MapperParsingException exception = assertThrows(
-            MapperParsingException.class,
-            () -> createMapperService(
-                fieldMapping,
-                true,
-                IndexVersions.V_8_0_0,
-                IndexVersionUtils.getPreviousVersion(IndexVersions.NEW_SPARSE_VECTOR)
-            )
-        );
-        assertTrue(exception.getMessage().contains(UNSUPPORTED_INDEX_MESSAGE));
-        assertTrue(exception.getRootCause() instanceof UnsupportedOperationException);
-    }
-
     public void testMultiFieldsSupport() throws IOException {
         if (useLegacyFormat) {
             Exception e = expectThrows(MapperParsingException.class, () -> createMapperService(fieldMapping(b -> {