Use synthetic recovery source by default if synthetic source is enabled

muted-tests.yml

@@ -143,6 +143,10 @@ tests:
 - class: org.elasticsearch.datastreams.DataStreamsClientYamlTestSuiteIT
   method: test {p0=data_stream/120_data_streams_stats/Multiple data stream}
   issue: https://github.com/elastic/elasticsearch/issues/118217
+- class: org.elasticsearch.test.rest.ClientYamlTestSuiteIT
+  method: test {p0=update/100_synthetic_source/keyword}
+- class: org.elasticsearch.test.rest.ClientYamlTestSuiteIT
+  method: test {p0=update/100_synthetic_source/stored text}
 - class: org.elasticsearch.action.search.SearchQueryThenFetchAsyncActionTests
   method: testBottomFieldSort
   issue: https://github.com/elastic/elasticsearch/issues/118214

rest-api-spec/src/yamlRestTest/resources/rest-api-spec/test/update/100_synthetic_source.yml

@@ -6,8 +6,8 @@ setup:
 ---
 keyword:
   - requires:
-      cluster_features: ["gte_v8.4.0"]
-      reason: introduced in 8.4.0
+      cluster_features: [ "index.recovery.synthetic_source_default" ]
+      reason: requires synthetic recovery source by default
 
   - do:
       indices.create:
@@ -60,13 +60,14 @@ keyword:
         index: test
         run_expensive_tasks: true
   - is_false: test.fields._source
-  - is_true: test.fields._recovery_source
+  # When synthetic source is used there is no _recovery_source field
+  - match: { test.fields._recovery_source: null }
 
 ---
 stored text:
   - requires:
-      cluster_features: ["gte_v8.5.0"]
-      reason: introduced in 8.5.0
+      cluster_features: [ "index.recovery.synthetic_source_default" ]
+      reason: requires synthetic recovery source by default
 
   - do:
       indices.create:
@@ -121,4 +122,5 @@ stored text:
         index: test
         run_expensive_tasks: true
   - is_false: test.fields._source
-  - is_true: test.fields._recovery_source
+  # When synthetic source is used there is no _recovery_source field
+  - match: { test.fields._recovery_source: null }

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

@@ -1580,6 +1580,15 @@ public static Setting<Boolean> boolSetting(String key, boolean defaultValue, Val
         return new Setting<>(key, Boolean.toString(defaultValue), booleanParser(key, properties), validator, properties);
     }
 
+    public static Setting<Boolean> boolSetting(
+        String key,
+        Function<Settings, String> defaultValueFn,
+        Validator<Boolean> validator,
+        Property... properties
+    ) {
+        return new Setting<>(key, defaultValueFn, booleanParser(key, properties), validator, properties);
+    }
+
     public static Setting<Boolean> boolSetting(String key, Function<Settings, String> defaultValueFn, Property... properties) {
         return new Setting<>(key, defaultValueFn, booleanParser(key, properties), properties);
     }

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

@@ -24,6 +24,7 @@
 import org.elasticsearch.common.time.DateUtils;
 import org.elasticsearch.common.unit.ByteSizeUnit;
 import org.elasticsearch.common.unit.ByteSizeValue;
+import org.elasticsearch.common.util.FeatureFlag;
 import org.elasticsearch.core.TimeValue;
 import org.elasticsearch.index.mapper.IgnoredSourceFieldMapper;
 import org.elasticsearch.index.mapper.Mapper;
@@ -39,6 +40,7 @@
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;
 
@@ -722,9 +724,25 @@ public Iterator<Setting<?>> settings() {
         Setting.Property.ServerlessPublic
     );
 
+    public static final FeatureFlag RECOVERY_USE_SYNTHETIC_SOURCE = new FeatureFlag("index_recovery_use_synthetic_source");
     public static final Setting<Boolean> RECOVERY_USE_SYNTHETIC_SOURCE_SETTING = Setting.boolSetting(
         "index.recovery.use_synthetic_source",
-        false,
+        settings -> {
+            boolean isSyntheticSourceRecoveryFeatureFlagEnabled = RECOVERY_USE_SYNTHETIC_SOURCE.isEnabled();
+            boolean isNewIndexVersion = SETTING_INDEX_VERSION_CREATED.get(settings)
+                .onOrAfter(IndexVersions.USE_SYNTHETIC_SOURCE_FOR_RECOVERY_BY_DEFAULT);
+            boolean isIndexVersionInBackportRange = SETTING_INDEX_VERSION_CREATED.get(settings)
+                .between(IndexVersions.USE_SYNTHETIC_SOURCE_FOR_RECOVERY_BY_DEFAULT_BACKPORT, IndexVersions.UPGRADE_TO_LUCENE_10_0_0);
+
+            boolean useSyntheticRecoverySource = isSyntheticSourceRecoveryFeatureFlagEnabled
+                && (isNewIndexVersion || isIndexVersionInBackportRange);
+
+            return String.valueOf(
+                useSyntheticRecoverySource
+                    && Objects.equals(INDEX_MAPPER_SOURCE_MODE_SETTING.get(settings), SourceFieldMapper.Mode.SYNTHETIC)
+            );
+
+        },
         new Setting.Validator<>() {
             @Override
             public void validate(Boolean value) {}
@@ -1083,7 +1101,8 @@ public IndexSettings(final IndexMetadata indexMetadata, final Settings nodeSetti
         skipIgnoredSourceRead = scopedSettings.get(IgnoredSourceFieldMapper.SKIP_IGNORED_SOURCE_READ_SETTING);
         indexMappingSourceMode = scopedSettings.get(INDEX_MAPPER_SOURCE_MODE_SETTING);
         recoverySourceEnabled = RecoverySettings.INDICES_RECOVERY_SOURCE_ENABLED_SETTING.get(nodeSettings);
-        recoverySourceSyntheticEnabled = scopedSettings.get(RECOVERY_USE_SYNTHETIC_SOURCE_SETTING);
+        recoverySourceSyntheticEnabled = DiscoveryNode.isStateless(nodeSettings) == false
+            && scopedSettings.get(RECOVERY_USE_SYNTHETIC_SOURCE_SETTING);
         if (recoverySourceSyntheticEnabled) {
             if (DiscoveryNode.isStateless(settings)) {
                 throw new IllegalArgumentException("synthetic recovery source is only allowed in stateful");

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

@@ -135,6 +135,7 @@ private static Version parseUnchecked(String version) {
     public static final IndexVersion UPGRADE_TO_LUCENE_9_12_1 = def(8_523_00_0, parseUnchecked("9.12.1"));
     public static final IndexVersion INFERENCE_METADATA_FIELDS_BACKPORT = def(8_524_00_0, parseUnchecked("9.12.1"));
     public static final IndexVersion LOGSB_OPTIONAL_SORTING_ON_HOST_NAME_BACKPORT = def(8_525_00_0, parseUnchecked("9.12.1"));
+    public static final IndexVersion USE_SYNTHETIC_SOURCE_FOR_RECOVERY_BY_DEFAULT_BACKPORT = def(8_526_00_0, parseUnchecked("9.12.1"));
     public static final IndexVersion UPGRADE_TO_LUCENE_10_0_0 = def(9_000_00_0, Version.LUCENE_10_0_0);
     public static final IndexVersion LOGSDB_DEFAULT_IGNORE_DYNAMIC_BEYOND_LIMIT = def(9_001_00_0, Version.LUCENE_10_0_0);
     public static final IndexVersion TIME_BASED_K_ORDERED_DOC_ID = def(9_002_00_0, Version.LUCENE_10_0_0);
@@ -145,6 +146,7 @@ private static Version parseUnchecked(String version) {
     public static final IndexVersion SOURCE_MAPPER_MODE_ATTRIBUTE_NOOP = def(9_007_00_0, Version.LUCENE_10_0_0);
     public static final IndexVersion HOSTNAME_DOC_VALUES_SPARSE_INDEX = def(9_008_00_0, Version.LUCENE_10_0_0);
     public static final IndexVersion UPGRADE_TO_LUCENE_10_1_0 = def(9_009_00_0, Version.LUCENE_10_1_0);
+    public static final IndexVersion USE_SYNTHETIC_SOURCE_FOR_RECOVERY_BY_DEFAULT = def(9_010_00_0, Version.LUCENE_10_1_0);
     /*
      * STOP! READ THIS FIRST! No, really,
      *        ____ _____ ___  ____  _        ____  _____    _    ____    _____ _   _ ___ ____    _____ ___ ____  ____ _____ _

server/src/test/java/org/elasticsearch/index/mapper/IgnoredSourceFieldMapperTests.java

@@ -2427,8 +2427,14 @@ protected void validateRoundTripReader(String syntheticSource, DirectoryReader r
         // and since the copy is exact, contents of ignored source are different.
         assertReaderEquals(
             "round trip " + syntheticSource,
-            new FieldMaskingReader(Set.of(SourceFieldMapper.RECOVERY_SOURCE_NAME, IgnoredSourceFieldMapper.NAME), reader),
-            new FieldMaskingReader(Set.of(SourceFieldMapper.RECOVERY_SOURCE_NAME, IgnoredSourceFieldMapper.NAME), roundTripReader)
+            new FieldMaskingReader(
+                Set.of(SourceFieldMapper.RECOVERY_SOURCE_NAME, IgnoredSourceFieldMapper.NAME, SourceFieldMapper.RECOVERY_SOURCE_SIZE_NAME),
+                reader
+            ),
+            new FieldMaskingReader(
+                Set.of(SourceFieldMapper.RECOVERY_SOURCE_NAME, IgnoredSourceFieldMapper.NAME, SourceFieldMapper.RECOVERY_SOURCE_SIZE_NAME),
+                roundTripReader
+            )
         );
     }
 }

server/src/test/java/org/elasticsearch/index/mapper/SourceFieldMapperTests.java

@@ -489,8 +489,13 @@ public void testRecoverySourceWithSyntheticSource() throws IOException {
             MapperService mapperService = createMapperService(settings, topMapping(b -> {}));
             DocumentMapper docMapper = mapperService.documentMapper();
             ParsedDocument doc = docMapper.parse(source(b -> b.field("field1", "value1")));
-            assertNotNull(doc.rootDoc().getField("_recovery_source"));
-            assertThat(doc.rootDoc().getField("_recovery_source").binaryValue(), equalTo(new BytesRef("{\"field1\":\"value1\"}")));
+            if (IndexSettings.RECOVERY_USE_SYNTHETIC_SOURCE.isEnabled() == false) {
+                // TODO: remove this if branch when removing the 'index_recovery_use_synthetic_source' feature flag
+                assertNotNull(doc.rootDoc().getField("_recovery_source"));
+                assertThat(doc.rootDoc().getField("_recovery_source").binaryValue(), equalTo(new BytesRef("{\"field1\":\"value1\"}")));
+            } else {
+                assertNull(doc.rootDoc().getField("_recovery_source"));
+            }
         }
         {
             Settings settings = Settings.builder()
@@ -521,8 +526,16 @@ public void testRecoverySourceWithLogs() throws IOException {
             MapperService mapperService = createMapperService(settings, mapping(b -> {}));
             DocumentMapper docMapper = mapperService.documentMapper();
             ParsedDocument doc = docMapper.parse(source(b -> { b.field("@timestamp", "2012-02-13"); }));
-            assertNotNull(doc.rootDoc().getField("_recovery_source"));
-            assertThat(doc.rootDoc().getField("_recovery_source").binaryValue(), equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\"}")));
+            if (IndexSettings.RECOVERY_USE_SYNTHETIC_SOURCE.isEnabled() == false) {
+                // TODO: remove this if branch when removing the 'index_recovery_use_synthetic_source' feature flag
+                assertNotNull(doc.rootDoc().getField("_recovery_source"));
+                assertThat(
+                    doc.rootDoc().getField("_recovery_source").binaryValue(),
+                    equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\"}"))
+                );
+            } else {
+                assertNull(doc.rootDoc().getField("_recovery_source"));
+            }
         }
         {
             Settings settings = Settings.builder()
@@ -715,8 +728,16 @@ public void testRecoverySourceWithLogsCustom() throws IOException {
             MapperService mapperService = createMapperService(settings, mappings);
             DocumentMapper docMapper = mapperService.documentMapper();
             ParsedDocument doc = docMapper.parse(source(b -> { b.field("@timestamp", "2012-02-13"); }));
-            assertNotNull(doc.rootDoc().getField("_recovery_source"));
-            assertThat(doc.rootDoc().getField("_recovery_source").binaryValue(), equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\"}")));
+            if (IndexSettings.RECOVERY_USE_SYNTHETIC_SOURCE.isEnabled() == false) {
+                // TODO: remove this if branch when removing the 'index_recovery_use_synthetic_source' feature flag
+                assertNotNull(doc.rootDoc().getField("_recovery_source"));
+                assertThat(
+                    doc.rootDoc().getField("_recovery_source").binaryValue(),
+                    equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\"}"))
+                );
+            } else {
+                assertNull(doc.rootDoc().getField("_recovery_source"));
+            }
         }
         {
             Settings settings = Settings.builder()
@@ -742,11 +763,16 @@ public void testRecoverySourceWithTimeSeries() throws IOException {
             }));
             DocumentMapper docMapper = mapperService.documentMapper();
             ParsedDocument doc = docMapper.parse(source("123", b -> b.field("@timestamp", "2012-02-13").field("field", "value1"), null));
-            assertNotNull(doc.rootDoc().getField("_recovery_source"));
-            assertThat(
-                doc.rootDoc().getField("_recovery_source").binaryValue(),
-                equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\",\"field\":\"value1\"}"))
-            );
+            if (IndexSettings.RECOVERY_USE_SYNTHETIC_SOURCE.isEnabled() == false) {
+                // TODO: remove this if branch when removing the 'index_recovery_use_synthetic_source' feature flag
+                assertNotNull(doc.rootDoc().getField("_recovery_source"));
+                assertThat(
+                    doc.rootDoc().getField("_recovery_source").binaryValue(),
+                    equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\",\"field\":\"value1\"}"))
+                );
+            } else {
+                assertNull(doc.rootDoc().getField("_recovery_source"));
+            }
         }
         {
             Settings settings = Settings.builder()
@@ -790,11 +816,16 @@ public void testRecoverySourceWithTimeSeriesCustom() throws IOException {
             MapperService mapperService = createMapperService(settings, mappings);
             DocumentMapper docMapper = mapperService.documentMapper();
             ParsedDocument doc = docMapper.parse(source("123", b -> b.field("@timestamp", "2012-02-13").field("field", "value1"), null));
-            assertNotNull(doc.rootDoc().getField("_recovery_source"));
-            assertThat(
-                doc.rootDoc().getField("_recovery_source").binaryValue(),
-                equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\",\"field\":\"value1\"}"))
-            );
+            if (IndexSettings.RECOVERY_USE_SYNTHETIC_SOURCE.isEnabled() == false) {
+                // TODO: remove this if branch when removing the 'index_recovery_use_synthetic_source' feature flag
+                assertNotNull(doc.rootDoc().getField("_recovery_source"));
+                assertThat(
+                    doc.rootDoc().getField("_recovery_source").binaryValue(),
+                    equalTo(new BytesRef("{\"@timestamp\":\"2012-02-13\",\"field\":\"value1\"}"))
+                );
+            } else {
+                assertNull(doc.rootDoc().getField("_recovery_source"));
+            }
         }
         {
             Settings settings = Settings.builder()

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

@@ -884,8 +884,11 @@ protected void validateRoundTripReader(String syntheticSource, DirectoryReader r
         throws IOException {
         assertReaderEquals(
             "round trip " + syntheticSource,
-            new FieldMaskingReader(SourceFieldMapper.RECOVERY_SOURCE_NAME, reader),
-            new FieldMaskingReader(SourceFieldMapper.RECOVERY_SOURCE_NAME, roundTripReader)
+            new FieldMaskingReader(Set.of(SourceFieldMapper.RECOVERY_SOURCE_NAME, SourceFieldMapper.RECOVERY_SOURCE_SIZE_NAME), reader),
+            new FieldMaskingReader(
+                Set.of(SourceFieldMapper.RECOVERY_SOURCE_NAME, SourceFieldMapper.RECOVERY_SOURCE_SIZE_NAME),
+                roundTripReader
+            )
         );
     }
 

x-pack/plugin/logsdb/build.gradle

@@ -42,3 +42,13 @@ tasks.named("javaRestTest").configure {
 tasks.named('yamlRestTest') {
   usesDefaultDistribution()
 }
+
+tasks.named("yamlRestTest") {
+  if (buildParams.isSnapshotBuild() == false) {
+    systemProperty 'tests.rest.blacklist', [
+      "resources/rest-api-spec/test/60_synthetic_source_recovery.yml"
+    ].join(',')
+  }
+}
+
+