Revert "Revert semantic_text model registry changes (#127075)"

This reverts commit e280aa5.

Author: jimczi

docs/changelog/126629.yaml

@@ -0,0 +1,5 @@
+pr: 126629
+summary: Default new `semantic_text` fields to use BBQ when models are compatible
+area: Relevance
+type: enhancement
+issues: []

server/src/main/java/org/elasticsearch/index/IndexVersions.java

@@ -161,6 +161,8 @@ private static Version parseUnchecked(String version) {
     public static final IndexVersion USE_LUCENE101_POSTINGS_FORMAT = def(9_021_0_00, Version.LUCENE_10_1_0);
     public static final IndexVersion UPGRADE_TO_LUCENE_10_2_0 = def(9_022_00_0, Version.LUCENE_10_2_0);
     public static final IndexVersion UPGRADE_TO_LUCENE_10_2_1 = def(9_023_00_0, Version.LUCENE_10_2_1);
+    public static final IndexVersion SEMANTIC_TEXT_DEFAULTS_TO_BBQ = def(9_024_0_00, Version.LUCENE_10_2_1);
+
     /*
      * STOP! READ THIS FIRST! No, really,
      *        ____ _____ ___  ____  _        ____  _____    _    ____    _____ _   _ ___ ____    _____ ___ ____  ____ _____ _

server/src/main/java/org/elasticsearch/index/mapper/vectors/DenseVectorFieldMapper.java

@@ -290,6 +290,11 @@ public Builder elementType(ElementType elementType) {
             return this;
         }
 
+        public Builder indexOptions(IndexOptions indexOptions) {
+            this.indexOptions.setValue(indexOptions);
+            return this;
+        }
+
         @Override
         public DenseVectorFieldMapper build(MapperBuilderContext context) {
             // Validate again here because the dimensions or element type could have been set programmatically,
@@ -1221,7 +1226,7 @@ public final String toString() {
         public abstract VectorSimilarityFunction vectorSimilarityFunction(IndexVersion indexVersion, ElementType elementType);
     }
 
-    abstract static class IndexOptions implements ToXContent {
+    public abstract static class IndexOptions implements ToXContent {
         final VectorIndexType type;
 
         IndexOptions(VectorIndexType type) {
@@ -1230,21 +1235,36 @@ abstract static class IndexOptions implements ToXContent {
 
         abstract KnnVectorsFormat getVectorsFormat(ElementType elementType);
 
-        final void validateElementType(ElementType elementType) {
-            if (type.supportsElementType(elementType) == false) {
+        public boolean validate(ElementType elementType, int dim, boolean throwOnError) {
+            return validateElementType(elementType, throwOnError) && validateDimension(dim, throwOnError);
+        }
+
+        public boolean validateElementType(ElementType elementType) {
+            return validateElementType(elementType, true);
+        }
+
+        final boolean validateElementType(ElementType elementType, boolean throwOnError) {
+            boolean validElementType = type.supportsElementType(elementType);
+            if (throwOnError && validElementType == false) {
                 throw new IllegalArgumentException(
                     "[element_type] cannot be [" + elementType.toString() + "] when using index type [" + type + "]"
                 );
             }
+            return validElementType;
         }
 
         abstract boolean updatableTo(IndexOptions update);
 
-        public void validateDimension(int dim) {
-            if (type.supportsDimension(dim)) {
-                return;
+        public boolean validateDimension(int dim) {
+            return validateDimension(dim, true);
+        }
+
+        public boolean validateDimension(int dim, boolean throwOnError) {
+            boolean supportsDimension = type.supportsDimension(dim);
+            if (throwOnError && supportsDimension == false) {
+                throw new IllegalArgumentException(type.name + " only supports even dimensions; provided=" + dim);
             }
-            throw new IllegalArgumentException(type.name + " only supports even dimensions; provided=" + dim);
+            return supportsDimension;
         }
 
         abstract boolean doEquals(IndexOptions other);
@@ -1747,12 +1767,12 @@ boolean updatableTo(IndexOptions update) {
 
     }
 
-    static class Int8HnswIndexOptions extends QuantizedIndexOptions {
+    public static class Int8HnswIndexOptions extends QuantizedIndexOptions {
         private final int m;
         private final int efConstruction;
         private final Float confidenceInterval;
 
-        Int8HnswIndexOptions(int m, int efConstruction, Float confidenceInterval, RescoreVector rescoreVector) {
+        public Int8HnswIndexOptions(int m, int efConstruction, Float confidenceInterval, RescoreVector rescoreVector) {
             super(VectorIndexType.INT8_HNSW, rescoreVector);
             this.m = m;
             this.efConstruction = efConstruction;
@@ -1890,11 +1910,11 @@ public String toString() {
         }
     }
 
-    static class BBQHnswIndexOptions extends QuantizedIndexOptions {
+    public static class BBQHnswIndexOptions extends QuantizedIndexOptions {
         private final int m;
         private final int efConstruction;
 
-        BBQHnswIndexOptions(int m, int efConstruction, RescoreVector rescoreVector) {
+        public BBQHnswIndexOptions(int m, int efConstruction, RescoreVector rescoreVector) {
             super(VectorIndexType.BBQ_HNSW, rescoreVector);
             this.m = m;
             this.efConstruction = efConstruction;
@@ -1936,11 +1956,14 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         }
 
         @Override
-        public void validateDimension(int dim) {
-            if (type.supportsDimension(dim)) {
-                return;
+        public boolean validateDimension(int dim, boolean throwOnError) {
+            boolean supportsDimension = type.supportsDimension(dim);
+            if (throwOnError && supportsDimension == false) {
+                throw new IllegalArgumentException(
+                    type.name + " does not support dimensions fewer than " + BBQ_MIN_DIMS + "; provided=" + dim
+                );
             }
-            throw new IllegalArgumentException(type.name + " does not support dimensions fewer than " + BBQ_MIN_DIMS + "; provided=" + dim);
+            return supportsDimension;
         }
     }
 
@@ -1984,15 +2007,19 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         }
 
         @Override
-        public void validateDimension(int dim) {
-            if (type.supportsDimension(dim)) {
-                return;
+        public boolean validateDimension(int dim, boolean throwOnError) {
+            boolean supportsDimension = type.supportsDimension(dim);
+            if (throwOnError && supportsDimension == false) {
+                throw new IllegalArgumentException(
+                    type.name + " does not support dimensions fewer than " + BBQ_MIN_DIMS + "; provided=" + dim
+                );
             }
-            throw new IllegalArgumentException(type.name + " does not support dimensions fewer than " + BBQ_MIN_DIMS + "; provided=" + dim);
+            return supportsDimension;
         }
+
     }
 
-    record RescoreVector(float oversample) implements ToXContentObject {
+    public record RescoreVector(float oversample) implements ToXContentObject {
         static final String NAME = "rescore_vector";
         static final String OVERSAMPLE = "oversample";
 
@@ -2311,6 +2338,10 @@ int getVectorDimensions() {
         ElementType getElementType() {
             return elementType;
         }
+
+        public IndexOptions getIndexOptions() {
+            return indexOptions;
+        }
     }
 
     private final IndexOptions indexOptions;

server/src/main/java/org/elasticsearch/inference/MinimalServiceSettings.java

@@ -249,18 +249,13 @@ private static void validateFieldNotPresent(String field, Object fieldValue, Tas
         }
     }
 
-    public ModelConfigurations toModelConfigurations(String inferenceEntityId) {
-        return new ModelConfigurations(inferenceEntityId, taskType, service == null ? UNKNOWN_SERVICE : service, this);
-    }
-
     /**
      * Checks if the given {@link MinimalServiceSettings} is equivalent to the current definition.
      */
     public boolean canMergeWith(MinimalServiceSettings other) {
         return taskType == other.taskType
             && Objects.equals(dimensions, other.dimensions)
             && similarity == other.similarity
-            && elementType == other.elementType
-            && (service == null || service.equals(other.service));
+            && elementType == other.elementType;
     }
 }

test/framework/src/main/java/org/elasticsearch/index/mapper/MapperServiceTestCase.java

@@ -207,6 +207,13 @@ protected final MapperService createMapperService(Settings settings, String mapp
         return mapperService;
     }
 
+    protected final MapperService createMapperService(IndexVersion indexVersion, Settings settings, XContentBuilder mappings)
+        throws IOException {
+        MapperService mapperService = createMapperService(indexVersion, settings, () -> true, mappings);
+        merge(mapperService, mappings);
+        return mapperService;
+    }
+
     protected final MapperService createMapperService(IndexVersion version, XContentBuilder mapping) throws IOException {
         return createMapperService(version, getIndexSettings(), () -> true, mapping);
     }