Unify logsdb index settings providers

x-pack/plugin/logsdb/src/main/java/org/elasticsearch/xpack/logsdb/LogsDBPlugin.java

@@ -43,7 +43,7 @@ public class LogsDBPlugin extends Plugin implements ActionPlugin {
     public LogsDBPlugin(Settings settings) {
         this.settings = settings;
         this.licenseService = new SyntheticSourceLicenseService(settings);
-        this.logsdbIndexModeSettingsProvider = new LogsdbIndexModeSettingsProvider(settings);
+        this.logsdbIndexModeSettingsProvider = new LogsdbIndexModeSettingsProvider(licenseService, settings);
     }
 
     @Override
@@ -67,16 +67,13 @@ public Collection<?> createComponents(PluginServices services) {
 
     @Override
     public Collection<IndexSettingProvider> getAdditionalIndexSettingProviders(IndexSettingProvider.Parameters parameters) {
-        if (DiscoveryNode.isStateless(settings)) {
-            return List.of(logsdbIndexModeSettingsProvider);
+        if (DiscoveryNode.isStateless(settings) == false) {
+            logsdbIndexModeSettingsProvider.init(
+                parameters.mapperServiceFactory(),
+                () -> parameters.clusterService().state().nodes().getMinSupportedIndexVersion()
+            );
         }
-        var syntheticSettingProvider = new SyntheticSourceIndexSettingsProvider(
-            licenseService,
-            parameters.mapperServiceFactory(),
-            logsdbIndexModeSettingsProvider,
-            () -> parameters.clusterService().state().nodes().getMinSupportedIndexVersion()
-        );
-        return List.of(syntheticSettingProvider, logsdbIndexModeSettingsProvider);
+        return List.of(logsdbIndexModeSettingsProvider);
     }
 
     @Override

x-pack/plugin/logsdb/src/main/java/org/elasticsearch/xpack/logsdb/LogsdbIndexModeSettingsProvider.java

@@ -7,53 +7,114 @@
 
 package org.elasticsearch.xpack.logsdb;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.apache.lucene.util.SetOnce;
+import org.elasticsearch.cluster.metadata.IndexMetadata;
 import org.elasticsearch.cluster.metadata.Metadata;
+import org.elasticsearch.common.UUIDs;
 import org.elasticsearch.common.compress.CompressedXContent;
 import org.elasticsearch.common.regex.Regex;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.core.CheckedFunction;
+import org.elasticsearch.core.Strings;
 import org.elasticsearch.index.IndexMode;
 import org.elasticsearch.index.IndexSettingProvider;
 import org.elasticsearch.index.IndexSettings;
+import org.elasticsearch.index.IndexVersion;
+import org.elasticsearch.index.mapper.MapperService;
+import org.elasticsearch.index.mapper.SourceFieldMapper;
 
+import java.io.IOException;
 import java.time.Instant;
 import java.util.List;
 import java.util.Locale;
+import java.util.function.Supplier;
 
+import static org.elasticsearch.cluster.metadata.IndexMetadata.INDEX_ROUTING_PATH;
 import static org.elasticsearch.xpack.logsdb.LogsDBPlugin.CLUSTER_LOGSDB_ENABLED;
 
 final class LogsdbIndexModeSettingsProvider implements IndexSettingProvider {
+    private static final Logger LOGGER = LogManager.getLogger(LogsdbIndexModeSettingsProvider.class);
     private static final String LOGS_PATTERN = "logs-*-*";
+
+    private final SyntheticSourceLicenseService syntheticSourceLicenseService;
+    private final SetOnce<CheckedFunction<IndexMetadata, MapperService, IOException>> mapperServiceFactory = new SetOnce<>();
+    private final SetOnce<Supplier<IndexVersion>> createdIndexVersion = new SetOnce<>();
+
     private volatile boolean isLogsdbEnabled;
 
-    LogsdbIndexModeSettingsProvider(final Settings settings) {
+    LogsdbIndexModeSettingsProvider(SyntheticSourceLicenseService syntheticSourceLicenseService, final Settings settings) {
+        this.syntheticSourceLicenseService = syntheticSourceLicenseService;
         this.isLogsdbEnabled = CLUSTER_LOGSDB_ENABLED.get(settings);
     }
 
     void updateClusterIndexModeLogsdbEnabled(boolean isLogsdbEnabled) {
         this.isLogsdbEnabled = isLogsdbEnabled;
     }
 
+    void init(CheckedFunction<IndexMetadata, MapperService, IOException> factory, Supplier<IndexVersion> indexVersion) {
+        mapperServiceFactory.set(factory);
+        createdIndexVersion.set(indexVersion);
+    }
+
+    private boolean supportSyntheticSourceDemotion() {
+        return mapperServiceFactory.get() != null;
+    }
+
+    @Override
+    public boolean overrulesTemplateAndRequestSettings() {
+        // Indicates that the provider value takes precedence over any user setting.
+        return true;
+    }
+
     @Override
     public Settings getAdditionalIndexSettings(
         final String indexName,
         final String dataStreamName,
         IndexMode templateIndexMode,
         final Metadata metadata,
         final Instant resolvedAt,
-        final Settings settings,
+        Settings indexTemplateAndCreateRequestSettings,
         final List<CompressedXContent> combinedTemplateMappings
     ) {
-        return getLogsdbModeSetting(dataStreamName, settings);
-    }
-
-    Settings getLogsdbModeSetting(final String dataStreamName, final Settings settings) {
+        Settings.Builder settingsBuilder = null;
         if (isLogsdbEnabled
             && dataStreamName != null
-            && resolveIndexMode(settings.get(IndexSettings.MODE.getKey())) == null
+            && resolveIndexMode(indexTemplateAndCreateRequestSettings.get(IndexSettings.MODE.getKey())) == null
             && matchesLogsPattern(dataStreamName)) {
-            return Settings.builder().put("index.mode", IndexMode.LOGSDB.getName()).build();
+            settingsBuilder = Settings.builder().put(IndexSettings.MODE.getKey(), IndexMode.LOGSDB.getName());
+            if (supportSyntheticSourceDemotion()) {
+                indexTemplateAndCreateRequestSettings = Settings.builder()
+                    .put(IndexSettings.MODE.getKey(), IndexMode.LOGSDB.getName())
+                    .put(indexTemplateAndCreateRequestSettings)
+                    .build();
+            }
+        }
+
+        if (supportSyntheticSourceDemotion()) {
+            // This index name is used when validating component and index templates, we should skip this check in that case.
+            // (See MetadataIndexTemplateService#validateIndexTemplateV2(...) method)
+            boolean isTemplateValidation = "validate-index-name".equals(indexName);
+            boolean legacyLicensedUsageOfSyntheticSourceAllowed = isLegacyLicensedUsageOfSyntheticSourceAllowed(
+                templateIndexMode,
+                indexName,
+                dataStreamName
+            );
+            if (newIndexHasSyntheticSourceUsage(
+                indexName,
+                templateIndexMode,
+                indexTemplateAndCreateRequestSettings,
+                combinedTemplateMappings
+            ) && syntheticSourceLicenseService.fallbackToStoredSource(isTemplateValidation, legacyLicensedUsageOfSyntheticSourceAllowed)) {
+                LOGGER.debug("creation of index [{}] with synthetic source without it being allowed", indexName);
+                if (settingsBuilder == null) {
+                    settingsBuilder = Settings.builder();
+                }
+                settingsBuilder.put(SourceFieldMapper.INDEX_MAPPER_SOURCE_MODE_SETTING.getKey(), SourceFieldMapper.Mode.STORED.toString());
+            }
         }
-        return Settings.EMPTY;
+        return settingsBuilder == null ? Settings.EMPTY : settingsBuilder.build();
     }
 
     private static boolean matchesLogsPattern(final String name) {
@@ -63,4 +124,106 @@ private static boolean matchesLogsPattern(final String name) {
     private IndexMode resolveIndexMode(final String mode) {
         return mode != null ? Enum.valueOf(IndexMode.class, mode.toUpperCase(Locale.ROOT)) : null;
     }
+
+    boolean newIndexHasSyntheticSourceUsage(
+        String indexName,
+        IndexMode templateIndexMode,
+        Settings indexTemplateAndCreateRequestSettings,
+        List<CompressedXContent> combinedTemplateMappings
+    ) {
+        if ("validate-index-name".equals(indexName)) {
+            // This index name is used when validating component and index templates, we should skip this check in that case.
+            // (See MetadataIndexTemplateService#validateIndexTemplateV2(...) method)
+            return false;
+        }
+
+        try {
+            var tmpIndexMetadata = buildIndexMetadataForMapperService(indexName, templateIndexMode, indexTemplateAndCreateRequestSettings);
+            var indexMode = tmpIndexMetadata.getIndexMode();
+            if (SourceFieldMapper.INDEX_MAPPER_SOURCE_MODE_SETTING.exists(tmpIndexMetadata.getSettings())
+                || indexMode == IndexMode.LOGSDB
+                || indexMode == IndexMode.TIME_SERIES) {
+                // In case when index mode is tsdb or logsdb and only _source.mode mapping attribute is specified, then the default
+                // could be wrong. However, it doesn't really matter, because if the _source.mode mapping attribute is set to stored,
+                // then configuring the index.mapping.source.mode setting to stored has no effect. Additionally _source.mode can't be set
+                // to disabled, because that isn't allowed with logsdb/tsdb. In other words setting index.mapping.source.mode setting to
+                // stored when _source.mode mapping attribute is stored is fine as it has no effect, but avoids creating MapperService.
+                var sourceMode = SourceFieldMapper.INDEX_MAPPER_SOURCE_MODE_SETTING.get(tmpIndexMetadata.getSettings());
+                return sourceMode == SourceFieldMapper.Mode.SYNTHETIC;
+            }
+
+            // TODO: remove this when _source.mode attribute has been removed:
+            try (var mapperService = mapperServiceFactory.get().apply(tmpIndexMetadata)) {
+                // combinedTemplateMappings can be null when creating system indices
+                // combinedTemplateMappings can be empty when creating a normal index that doesn't match any template and without mapping.
+                if (combinedTemplateMappings == null || combinedTemplateMappings.isEmpty()) {
+                    combinedTemplateMappings = List.of(new CompressedXContent("{}"));
+                }
+                mapperService.merge(MapperService.SINGLE_MAPPING_NAME, combinedTemplateMappings, MapperService.MergeReason.INDEX_TEMPLATE);
+                return mapperService.documentMapper().sourceMapper().isSynthetic();
+            }
+        } catch (AssertionError | Exception e) {
+            // In case invalid mappings or setting are provided, then mapper service creation can fail.
+            // In that case it is ok to return false here. The index creation will fail anyway later, so no need to fallback to stored
+            // source.
+            LOGGER.info(() -> Strings.format("unable to create mapper service for index [%s]", indexName), e);
+            return false;
+        }
+    }
+
+    // Create a dummy IndexMetadata instance that can be used to create a MapperService in order to check whether synthetic source is used:
+    private IndexMetadata buildIndexMetadataForMapperService(
+        String indexName,
+        IndexMode templateIndexMode,
+        Settings indexTemplateAndCreateRequestSettings
+    ) {
+        var tmpIndexMetadata = IndexMetadata.builder(indexName);
+
+        int dummyPartitionSize = IndexMetadata.INDEX_ROUTING_PARTITION_SIZE_SETTING.get(indexTemplateAndCreateRequestSettings);
+        int dummyShards = indexTemplateAndCreateRequestSettings.getAsInt(
+            IndexMetadata.SETTING_NUMBER_OF_SHARDS,
+            dummyPartitionSize == 1 ? 1 : dummyPartitionSize + 1
+        );
+        int shardReplicas = indexTemplateAndCreateRequestSettings.getAsInt(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 0);
+        var finalResolvedSettings = Settings.builder()
+            .put(IndexMetadata.SETTING_VERSION_CREATED, createdIndexVersion.get().get())
+            .put(indexTemplateAndCreateRequestSettings)
+            .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, dummyShards)
+            .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, shardReplicas)
+            .put(IndexMetadata.SETTING_INDEX_UUID, UUIDs.randomBase64UUID());
+
+        if (templateIndexMode == IndexMode.TIME_SERIES) {
+            finalResolvedSettings.put(IndexSettings.MODE.getKey(), IndexMode.TIME_SERIES);
+            // Avoid failing because index.routing_path is missing (in case fields are marked as dimension)
+            finalResolvedSettings.putList(INDEX_ROUTING_PATH.getKey(), List.of("path"));
+        }
+
+        tmpIndexMetadata.settings(finalResolvedSettings);
+        return tmpIndexMetadata.build();
+    }
+
+    /**
+     * The GA-ed use cases in which synthetic source usage is allowed with gold or platinum license.
+     */
+    private boolean isLegacyLicensedUsageOfSyntheticSourceAllowed(IndexMode templateIndexMode, String indexName, String dataStreamName) {
+        if (templateIndexMode == IndexMode.TIME_SERIES) {
+            return true;
+        }
+
+        // To allow the following patterns: profiling-metrics and profiling-events
+        if (dataStreamName != null && dataStreamName.startsWith("profiling-")) {
+            return true;
+        }
+        // To allow the following patterns: .profiling-sq-executables, .profiling-sq-leafframes and .profiling-stacktraces
+        if (indexName.startsWith(".profiling-")) {
+            return true;
+        }
+        // To allow the following patterns: metrics-apm.transaction.*, metrics-apm.service_transaction.*, metrics-apm.service_summary.*,
+        // metrics-apm.service_destination.*, "metrics-apm.internal-* and metrics-apm.app.*
+        if (dataStreamName != null && dataStreamName.startsWith("metrics-apm.")) {
+            return true;
+        }
+
+        return false;
+    }
 }