Introduce a new setting and a feature flag for the synthetic vectors mode in mappings

Author: jimczi

server/src/main/java/org/elasticsearch/common/settings/IndexScopedSettings.java

@@ -49,6 +49,8 @@
 import java.util.Map;
 import java.util.Set;
 
+import static org.elasticsearch.index.IndexSettings.SYNTHETIC_VECTORS;
+
 /**
  * Encapsulates all valid index level settings.
  * @see Property#IndexScope
@@ -240,6 +242,9 @@ public final class IndexScopedSettings extends AbstractScopedSettings {
         if (IndexSettings.DOC_VALUES_SKIPPER) {
             settings.add(IndexSettings.USE_DOC_VALUES_SKIPPER);
         }
+        if (SYNTHETIC_VECTORS) {
+            settings.add(IndexSettings.INDEX_MAPPING_SOURCE_SYNTHETIC_VECTORS_SETTING);
+        }
         BUILT_IN_INDEX_SETTINGS = Collections.unmodifiableSet(settings);
     };
 

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

@@ -847,6 +847,14 @@ private static String getIgnoreAboveDefaultValue(final Settings settings) {
         Property.Final
     );
 
+    public static final boolean SYNTHETIC_VECTORS = new FeatureFlag("mapping_synthetic_vectors").isEnabled();
+    public static final Setting<Boolean> INDEX_MAPPING_SOURCE_SYNTHETIC_VECTORS_SETTING = Setting.boolSetting(
+        "index.mapping.synthetic_vectors",
+        false,
+        Property.IndexScope,
+        Property.Final
+    );
+
     private final Index index;
     private final IndexVersion version;
     private final Logger logger;
@@ -890,7 +898,7 @@ private static String getIgnoreAboveDefaultValue(final Settings settings) {
     private final boolean logsdbRouteOnSortFields;
     private final boolean logsdbSortOnHostName;
     private final boolean logsdbAddHostNameField;
-
+    private volatile boolean searchExcludeVectors;
     private volatile long retentionLeaseMillis;
 
     /**