Fix the calculation of the requested number of documents.

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

@@ -120,9 +120,6 @@ class RequestConverter extends AbstractQueryProcessor {
 
 	private static final Log LOGGER = LogFactory.getLog(RequestConverter.class);
 
-	// the default max result window size of Elasticsearch
-	public static final Integer INDEX_MAX_RESULT_WINDOW = 10_000;
-
 	protected final JsonpMapper jsonpMapper;
 	protected final ElasticsearchConverter elasticsearchConverter;
 
@@ -751,9 +748,9 @@ private CreateOperation<?> bulkCreateOperation(IndexQuery query, IndexCoordinate
 		}
 		return co.elastic.clients.elasticsearch._types.Script.of(sb -> {
 			sb.lang(scriptData.language())
-			  	.params(params)
-				.id(scriptData.scriptName());
-			if (scriptData.script() != null){
+					.params(params)
+					.id(scriptData.scriptName());
+			if (scriptData.script() != null) {
 				sb.source(s -> s.scriptString(scriptData.script()));
 			}
 			return sb;
@@ -927,7 +924,7 @@ public co.elastic.clients.elasticsearch.core.ReindexRequest reindex(ReindexReque
 		ReindexRequest.Script script = reindexRequest.getScript();
 		if (script != null) {
 			builder.script(sb -> {
-				if (script.getSource() != null){
+				if (script.getSource() != null) {
 					sb.source(s -> s.scriptString(script.getSource()));
 				}
 				sb.lang(script.getLang());
@@ -1089,7 +1086,7 @@ public DeleteByQueryRequest documentDeleteByQueryRequest(DeleteQuery query, @Nul
 
 				uqb.script(sb -> {
 					sb.lang(query.getLang()).params(params);
-					if (query.getScript() != null){
+					if (query.getScript() != null) {
 						sb.source(s -> s.scriptString(query.getScript()));
 					}
 					sb.id(query.getId());
@@ -1257,8 +1254,8 @@ public MsearchTemplateRequest searchMsearchTemplateRequest(
 						.header(msearchHeaderBuilder(query, param.index(), routing))
 						.body(bb -> {
 							bb.explain(query.getExplain()) //
-								.id(query.getId()); //
-							if (query.getSource() != null){
+									.id(query.getId()); //
+							if (query.getSource() != null) {
 								bb.source(s -> s.scriptString(query.getSource()));
 							}
 
@@ -1296,15 +1293,8 @@ public MsearchRequest searchMsearchRequest(
 									.timeout(timeStringMs(query.getTimeout())) //
 							;
 
-							var offset = query.getPageable().isPaged() ? query.getPageable().getOffset() : 0;
-							var pageSize = query.getPageable().isPaged() ? query.getPageable().getPageSize()
-									: INDEX_MAX_RESULT_WINDOW;
-							// if we have both a page size and a max results, we take the min, this is necessary for
-							// searchForStream to work correctly (#3098) as there the page size defines what is
-							// returned in a single request, and the max result determines the total number of
-							// documents returned
-							var size = query.isLimiting() ? Math.min(pageSize, query.getMaxResults()) : pageSize;
-							bb.from((int) offset).size(size);
+                            bb.from((int) (query.getPageable().isPaged() ? query.getPageable().getOffset() : 0))
+									.size(query.getRequestSize());
 
 							if (!isEmpty(query.getFields())) {
 								bb.fields(fb -> {
@@ -1476,14 +1466,8 @@ private <T> void prepareSearchRequest(Query query, @Nullable String routing, @Nu
 			builder.seqNoPrimaryTerm(true);
 		}
 
-		var offset = query.getPageable().isPaged() ? query.getPageable().getOffset() : 0;
-		var pageSize = query.getPageable().isPaged() ? query.getPageable().getPageSize() : INDEX_MAX_RESULT_WINDOW;
-		// if we have both a page size and a max results, we take the min, this is necessary for
-		// searchForStream to work correctly (#3098) as there the page size defines what is
-		// returned in a single request, and the max result determines the total number of
-		// documents returned
-		var size = query.isLimiting() ? Math.min(pageSize, query.getMaxResults()) : pageSize;
-		builder.from((int) offset).size(size);
+        builder.from((int) (query.getPageable().isPaged() ? query.getPageable().getOffset() : 0))
+				.size(query.getRequestSize());
 
 		if (!isEmpty(query.getFields())) {
 			var fieldAndFormats = query.getFields().stream().map(field -> FieldAndFormat.of(b -> b.field(field))).toList();
@@ -1943,8 +1927,8 @@ public PutScriptRequest scriptPut(Script script) {
 		return PutScriptRequest.of(b -> b //
 				.id(script.id()) //
 				.script(sb -> sb //
-					.lang(script.language()) //
-					.source(s -> s.scriptString(script.source()))));
+						.lang(script.language()) //
+						.source(s -> s.scriptString(script.source()))));
 	}
 
 	public GetScriptRequest scriptGet(String name) {

src/main/java/org/springframework/data/elasticsearch/core/query/BaseQuery.java

@@ -28,6 +28,7 @@
 import java.util.stream.Collectors;
 
 import org.jspecify.annotations.Nullable;
+import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Sort;
 import org.springframework.util.Assert;
@@ -47,10 +48,15 @@
  */
 public class BaseQuery implements Query {
 
+	public static final int INDEX_MAX_RESULT_WINDOW = 10_000;
+
 	private static final int DEFAULT_REACTIVE_BATCH_SIZE = 500;
+	// the instance to mark the query pageable initial status, needed to distinguish between the initial
+	// value and a user-set unpaged value; values don't matter, the RequestConverter compares to the isntance.
+	private static final Pageable UNSET_PAGE = PageRequest.of(0, 1);
 
 	@Nullable protected Sort sort;
-	protected Pageable pageable = DEFAULT_PAGE;
+	protected Pageable pageable = UNSET_PAGE;
 	protected List<String> fields = new ArrayList<>();
 	@Nullable protected List<String> storedFields;
 	@Nullable protected SourceFilter sourceFilter;
@@ -78,7 +84,7 @@ public class BaseQuery implements Query {
 	private boolean queryIsUpdatedByConverter = false;
 	@Nullable private Integer reactiveBatchSize = null;
 	@Nullable private Boolean allowNoIndices = null;
-	private EnumSet<IndicesOptions.WildcardStates> expandWildcards;
+	private EnumSet<IndicesOptions.WildcardStates> expandWildcards = EnumSet.noneOf(IndicesOptions.WildcardStates.class);
 	private List<DocValueField> docValueFields = new ArrayList<>();
 	private List<ScriptedField> scriptedFields = new ArrayList<>();
 
@@ -87,7 +93,7 @@ public BaseQuery() {}
 	public <Q extends BaseQuery, B extends BaseQueryBuilder<Q, B>> BaseQuery(BaseQueryBuilder<Q, B> builder) {
 		this.sort = builder.getSort();
 		// do a setPageable after setting the sort, because the pageable may contain an additional sort
-		this.setPageable(builder.getPageable() != null ? builder.getPageable() : DEFAULT_PAGE);
+		this.setPageable(builder.getPageable() != null ? builder.getPageable() : UNSET_PAGE);
 		this.fields = builder.getFields();
 		this.storedFields = builder.getStoredFields();
 		this.sourceFilter = builder.getSourceFilter();
@@ -203,7 +209,7 @@ public SourceFilter getSourceFilter() {
 	@Override
 	@SuppressWarnings("unchecked")
 	public final <T extends Query> T addSort(@Nullable Sort sort) {
-		if (sort == null) {
+		if (sort == null || sort.isUnsorted()) {
 			return (T) this;
 		}
 
@@ -561,4 +567,52 @@ public void addScriptedField(ScriptedField scriptedField) {
 	public List<ScriptedField> getScriptedFields() {
 		return scriptedFields;
 	}
+
+	@Override
+	public Integer getRequestSize() {
+
+		var pageable = getPageable();
+		Integer requestSize = null;
+
+		if (pageable.isPaged() && pageable != UNSET_PAGE) {
+			// pagesize defined by the user
+			if (!isLimiting()) {
+				// no maxResults
+				requestSize = pageable.getPageSize();
+			} else {
+				// if we have both a page size and a max results, we take the min, this is necessary for
+				// searchForStream to work correctly (#3098) as there the page size defines what is
+				// returned in a single request, and the max result determines the total number of
+				// documents returned.
+				requestSize = Math.min(pageable.getPageSize(), getMaxResults());
+			}
+		} else if (pageable == UNSET_PAGE) {
+			// no user defined pageable
+			if (isLimiting()) {
+				// maxResults
+				requestSize = getMaxResults();
+			} else {
+				requestSize = DEFAULT_PAGE_SIZE;
+			}
+		} else {
+			// explicitly set unpaged
+			if (!isLimiting()) {
+				// no maxResults
+				requestSize = INDEX_MAX_RESULT_WINDOW;
+			} else {
+				// if we have both a implicit page size and a max results, we take the min, this is necessary for
+				// searchForStream to work correctly (#3098) as there the page size defines what is
+				// returned in a single request, and the max result determines the total number of
+				// documents returned.
+				requestSize = Math.min(INDEX_MAX_RESULT_WINDOW, getMaxResults());
+			}
+		}
+
+		if (requestSize == null) {
+			// this should not happen
+			requestSize = DEFAULT_PAGE_SIZE;
+		}
+
+		return requestSize;
+	}
 }

src/main/java/org/springframework/data/elasticsearch/core/query/Query.java

@@ -484,6 +484,13 @@ default Integer getReactiveBatchSize() {
 	 */
 	List<ScriptedField> getScriptedFields();
 
+	/**
+	 * @return the number of documents that should be requested from Elasticsearch in this query. Depends wether a
+	 *         Pageable and/or maxResult size is set on the query.
+	 * @since 5.4.8 5.5.2
+	 */
+	public Integer getRequestSize();
+
 	/**
 	 * @since 4.3
 	 */

src/test/java/org/springframework/data/elasticsearch/core/ElasticsearchIntegrationTests.java

@@ -104,8 +104,6 @@
 @SpringIntegrationTest
 public abstract class ElasticsearchIntegrationTests {
 
-	static final Integer INDEX_MAX_RESULT_WINDOW = 10_000;
-
 	private static final String MULTI_INDEX_PREFIX = "test-index";
 	private static final String MULTI_INDEX_ALL = MULTI_INDEX_PREFIX + "*";
 	private static final String MULTI_INDEX_1_NAME = MULTI_INDEX_PREFIX + "-1";

src/test/java/org/springframework/data/elasticsearch/core/query/BaseQueryTests.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright 2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.elasticsearch.core.query;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.springframework.data.elasticsearch.core.query.BaseQuery.*;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.data.domain.Pageable;
+
+class BaseQueryTests {
+
+	private static final String MATCH_ALL_QUERY = "{\"match_all\":{}}";
+
+	@Test // #3127
+	@DisplayName("query with no Pageable and no maxResults requests 10 docs from 0")
+	void queryWithNoPageableAndNoMaxResultsRequests10DocsFrom0() {
+
+		var query = StringQuery.builder(MATCH_ALL_QUERY)
+				.build();
+
+		var requestSize = query.getRequestSize();
+
+		assertThat(requestSize).isEqualTo(10);
+	}
+
+	@Test // #3127
+	@DisplayName("query with a Pageable and no MaxResults request with values from Pageable")
+	void queryWithAPageableAndNoMaxResultsRequestWithValuesFromPageable() {
+		var query = StringQuery.builder(MATCH_ALL_QUERY)
+				.withPageable(Pageable.ofSize(42))
+				.build();
+
+		var requestSize = query.getRequestSize();
+
+		assertThat(requestSize).isEqualTo(42);
+	}
+
+	@Test // #3127
+	@DisplayName("query with no Pageable and maxResults requests maxResults")
+	void queryWithNoPageableAndMaxResultsRequestsMaxResults() {
+
+		var query = StringQuery.builder(MATCH_ALL_QUERY)
+				.withMaxResults(12_345)
+				.build();
+
+		var requestSize = query.getRequestSize();
+
+		assertThat(requestSize).isEqualTo(12_345);
+	}
+
+	@Test // #3127
+	@DisplayName("query with Pageable and maxResults requests with values from Pageable if Pageable is less than maxResults")
+	void queryWithPageableAndMaxResultsRequestsWithValuesFromPageableIfPageableIsLessThanMaxResults() {
+
+		var query = StringQuery.builder(MATCH_ALL_QUERY)
+				.withPageable(Pageable.ofSize(42))
+				.withMaxResults(123)
+				.build();
+
+		var requestSize = query.getRequestSize();
+
+		assertThat(requestSize).isEqualTo(42);
+	}
+
+	@Test // #3127
+	@DisplayName("query with Pageable and maxResults requests with values from maxResults if Pageable is more than maxResults")
+	void queryWithPageableAndMaxResultsRequestsWithValuesFromMaxResultsIfPageableIsMoreThanMaxResults() {
+
+		var query = StringQuery.builder(MATCH_ALL_QUERY)
+				.withPageable(Pageable.ofSize(420))
+				.withMaxResults(123)
+				.build();
+
+		var requestSize = query.getRequestSize();
+
+		assertThat(requestSize).isEqualTo(123);
+	}
+
+	@Test // #3127
+	@DisplayName("query with explicit unpaged request and no maxResults requests max request window size")
+	void queryWithExplicitUnpagedRequestAndNoMaxResultsRequestsMaxRequestWindowSize() {
+
+		var query = StringQuery.builder(MATCH_ALL_QUERY)
+				.withPageable(Pageable.unpaged())
+				.build();
+
+		var requestSize = query.getRequestSize();
+
+		assertThat(requestSize).isEqualTo(INDEX_MAX_RESULT_WINDOW);
+	}
+}