Support for DynamicTemplates.

src/main/java/org/springframework/data/elasticsearch/annotations/Field.java

@@ -252,4 +252,11 @@
 	 * @since 5.4
 	 */
 	String mappedTypeName() default "";
+
+	/**
+	 * Maps your data beyond the dynamic field mapping rules.
+	 * 
+	 * @since 5.4
+	 */
+	boolean dynamicTemplate() default false;
 }

src/main/java/org/springframework/data/elasticsearch/client/elc/IndicesTemplate.java

@@ -80,7 +80,6 @@ public IndicesTemplate(ElasticsearchIndicesClient client, ClusterTemplate cluste
 		this.elasticsearchConverter = elasticsearchConverter;
 		this.boundClass = boundClass;
 		this.boundIndex = null;
-
 	}
 
 	public IndicesTemplate(ElasticsearchIndicesClient client, ClusterTemplate clusterTemplate,
@@ -95,7 +94,6 @@ public IndicesTemplate(ElasticsearchIndicesClient client, ClusterTemplate cluste
 		this.elasticsearchConverter = elasticsearchConverter;
 		this.boundClass = null;
 		this.boundIndex = boundIndex;
-
 	}
 
 	protected Class<?> checkForBoundClass() {
@@ -145,6 +143,8 @@ protected boolean doCreate(IndexCoordinates indexCoordinates, Map<String, Object
 
 		CreateIndexRequest createIndexRequest = requestConverter.indicesCreateRequest(indexSettings);
 		CreateIndexResponse createIndexResponse = execute(client -> client.create(createIndexRequest));
+		// refresh cached mappings
+		refreshMapping();
 		return Boolean.TRUE.equals(createIndexResponse.acknowledged());
 	}
 
@@ -241,6 +241,28 @@ public Map<String, Object> getMapping() {
 		return responseConverter.indicesGetMapping(getMappingResponse, indexCoordinates);
 	}
 
+	/**
+	 * Refreshes the mapping for the current entity.
+	 * <p>
+	 * This method is responsible for retrieving and updating the metadata related to the current entity.
+	 */
+	private void refreshMapping() {
+		if (boundClass == null) {
+			return;
+		}
+
+		ElasticsearchPersistentEntity<?> entity = this.elasticsearchConverter.getMappingContext()
+				.getPersistentEntity(boundClass);
+		if (entity == null) {
+			return;
+		}
+
+		Object dynamicTemplates = getMapping().get("dynamic_templates");
+		if (dynamicTemplates instanceof List<?> value) {
+			entity.buildDynamicTemplates(value);
+		}
+	}
+
 	@Override
 	public Settings createSettings() {
 		return createSettings(checkForBoundClass());

src/main/java/org/springframework/data/elasticsearch/client/elc/ReactiveIndicesTemplate.java

@@ -25,6 +25,7 @@
 import reactor.core.publisher.Mono;
 
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
@@ -142,7 +143,12 @@ private Mono<Boolean> doCreate(IndexCoordinates indexCoordinates, Map<String, Ob
 
 		CreateIndexRequest createIndexRequest = requestConverter.indicesCreateRequest(indexSettings);
 		Mono<CreateIndexResponse> createIndexResponse = Mono.from(execute(client -> client.create(createIndexRequest)));
-		return createIndexResponse.map(CreateIndexResponse::acknowledged);
+		return createIndexResponse
+				.doOnNext((result) -> {
+					// refresh cached mappings
+					refreshMapping();
+				})
+				.map(CreateIndexResponse::acknowledged);
 	}
 
 	@Override
@@ -218,6 +224,30 @@ public Mono<Document> getMapping() {
 		return getMappingResponse.map(response -> responseConverter.indicesGetMapping(response, indexCoordinates));
 	}
 
+	/**
+	 * Refreshes the mapping for the current entity.
+	 * <p>
+	 * This method is responsible for retrieving and updating the metadata related to the current entity.
+	 */
+	private void refreshMapping() {
+		if (boundClass == null) {
+			return;
+		}
+
+		ElasticsearchPersistentEntity<?> entity = this.elasticsearchConverter.getMappingContext()
+				.getPersistentEntity(boundClass);
+		if (entity == null) {
+			return;
+		}
+
+		getMapping().subscribe((mappings) -> {
+			Object dynamicTemplates = mappings.get("dynamic_templates");
+			if (dynamicTemplates instanceof List<?> value) {
+				entity.buildDynamicTemplates(value);
+			}
+		});
+	}
+
 	@Override
 	public Mono<Settings> createSettings() {
 		return createSettings(checkForBoundClass());

src/main/java/org/springframework/data/elasticsearch/core/convert/MappingElasticsearchConverter.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.elasticsearch.core.convert;
 
+import static org.springframework.util.PatternMatchUtils.simpleMatch;
+
 import java.time.temporal.TemporalAccessor;
 import java.util.*;
 import java.util.Map.Entry;
@@ -42,6 +44,7 @@
 import org.springframework.data.elasticsearch.annotations.ScriptedField;
 import org.springframework.data.elasticsearch.core.document.Document;
 import org.springframework.data.elasticsearch.core.document.SearchDocument;
+import org.springframework.data.elasticsearch.core.mapping.DynamicTemplate;
 import org.springframework.data.elasticsearch.core.mapping.ElasticsearchPersistentEntity;
 import org.springframework.data.elasticsearch.core.mapping.ElasticsearchPersistentProperty;
 import org.springframework.data.elasticsearch.core.mapping.PropertyValueConverter;
@@ -388,6 +391,10 @@ private <R> R readEntity(ElasticsearchPersistentEntity<?> entity, Map<String, Ob
 							targetEntity.getPropertyAccessor(result).setProperty(property, seqNoPrimaryTerm);
 						}
 					}
+
+					if (targetEntity.hasDynamicTemplates()) {
+						populateFieldsUsingDynamicTemplates(targetEntity, result, document);
+					}
 				}
 
 				if (source instanceof SearchDocument searchDocument) {
@@ -664,6 +671,28 @@ private <T> void populateScriptFields(ElasticsearchPersistentEntity<?> entity, T
 			});
 		}
 
+		private <R> void populateFieldsUsingDynamicTemplates(ElasticsearchPersistentEntity<?> targetEntity, R result,
+				Document document) {
+			for (Entry<String, DynamicTemplate> templateEntry : targetEntity.getDynamicTemplates().entrySet()) {
+				ElasticsearchPersistentProperty property = targetEntity
+						.getPersistentPropertyWithFieldName(templateEntry.getKey());
+				if (property != null && property.isDynamicFieldMapping()) {
+					// prepare value
+					Map<String, Object> values = new HashMap<>();
+					// TODO: Path match and unmatched
+					document.entrySet().stream()
+							.filter(fieldKey -> templateEntry.getValue().getMatch().stream()
+									.anyMatch(regex -> simpleMatch(regex, fieldKey.getKey()))
+									&& templateEntry.getValue().getUnmatch().stream()
+											.noneMatch(regex -> simpleMatch(regex, fieldKey.getKey())))
+							.forEach(entry -> values.put(entry.getKey(), entry.getValue()));
+
+					// set property
+					targetEntity.getPropertyAccessor(result).setProperty(property, read(property.getType(), Document.from(values)));
+				}
+			}
+		}
+
 		/**
 		 * Compute the type to use by checking the given entity against the store type;
 		 */
@@ -1035,7 +1064,14 @@ protected void writeProperty(ElasticsearchPersistentProperty property, Object va
 
 			if (valueType.isMap()) {
 				Map<String, Object> mapDbObj = createMap((Map<?, ?>) value, property);
-				sink.set(property, mapDbObj);
+				if (property.isDynamicFieldMapping()) {
+					for (Entry<String, Object> entry : mapDbObj.entrySet()) {
+						sink.set(entry.getKey(), entry.getValue());
+					}
+				} else {
+					sink.set(property, mapDbObj);
+				}
+
 				return;
 			}
 
@@ -1058,7 +1094,14 @@ protected void writeProperty(ElasticsearchPersistentProperty property, Object va
 
 			addCustomTypeKeyIfNecessary(value, document, TypeInformation.of(property.getRawType()));
 			writeInternal(value, document, entity);
-			sink.set(property, document);
+			if (property.isDynamicFieldMapping()) {
+				// flatten
+				for (Entry<String, Object> entry : document.entrySet()) {
+					sink.set(entry.getKey(), entry.getValue());
+				}
+			} else {
+				sink.set(property, document);
+			}
 		}
 
 		/**
@@ -1499,7 +1542,11 @@ public void set(ElasticsearchPersistentProperty property, @Nullable Object value
 				}
 			}
 
-			target.put(property.getFieldName(), value);
+			set(property.getFieldName(), value);
+		}
+
+		public void set(String key, @Nullable Object value) {
+			target.put(key, value);
 		}
 
 		private Map<String, Object> getAsMap(Object result) {