[Segment Replication] Introduce cluster level setting `cluster.index.…

…restrict.replication.type` to prevent replication type setting override during index creations (opensearch-project#11583)

* Add new cluster level setting that prevents index level replication type setting overrides

Signed-off-by: Suraj Singh <surajrider@gmail.com>

* Block restore on mis-matching replication type setting

Signed-off-by: Suraj Singh <surajrider@gmail.com>

* Address review comments and rebase

Signed-off-by: Suraj Singh <surajrider@gmail.com>

* Address review comments

Signed-off-by: Suraj Singh <surajrider@gmail.com>

* Use appropriate variable names

Signed-off-by: Suraj Singh <surajrider@gmail.com>

* Fix failing integ test

Signed-off-by: Suraj Singh <surajrider@gmail.com>

---------

Signed-off-by: Suraj Singh <surajrider@gmail.com>

CHANGELOG.md

@@ -122,6 +122,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - [BWC and API enforcement] Introduce checks for enforcing the API restrictions ([#11175](https://github.com/opensearch-project/OpenSearch/pull/11175))
 - Create separate transport action for render search template action ([#11170](https://github.com/opensearch-project/OpenSearch/pull/11170))
 - Add additional handling in SearchTemplateRequest when simulate is set to true ([#11591](https://github.com/opensearch-project/OpenSearch/pull/11591))
+- Introduce cluster level setting `cluster.index.restrict.replication.type` to prevent replication type setting override during index creations([#11583](https://github.com/opensearch-project/OpenSearch/pull/11583))
 
 ### Dependencies
 - Bump Lucene from 9.7.0 to 9.8.0 ([10276](https://github.com/opensearch-project/OpenSearch/pull/10276))

server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationClusterSettingIT.java

@@ -10,16 +10,26 @@
 
 import org.opensearch.action.admin.indices.settings.get.GetSettingsRequest;
 import org.opensearch.action.admin.indices.settings.get.GetSettingsResponse;
+import org.opensearch.action.admin.indices.shrink.ResizeType;
+import org.opensearch.action.admin.indices.template.get.GetIndexTemplatesResponse;
 import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.common.collect.Tuple;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.core.index.Index;
 import org.opensearch.index.IndexModule;
 import org.opensearch.indices.IndicesService;
 import org.opensearch.indices.replication.common.ReplicationType;
 import org.opensearch.test.OpenSearchIntegTestCase;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Locale;
+
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_REPLICATION_TYPE;
+import static org.opensearch.indices.IndicesService.CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING;
 import static org.opensearch.indices.IndicesService.CLUSTER_SETTING_REPLICATION_TYPE;
+import static org.hamcrest.Matchers.hasSize;
 
 @OpenSearchIntegTestCase.ClusterScope(scope = OpenSearchIntegTestCase.Scope.TEST, numDataNodes = 0)
 public class SegmentReplicationClusterSettingIT extends OpenSearchIntegTestCase {
@@ -29,6 +39,9 @@ public class SegmentReplicationClusterSettingIT extends OpenSearchIntegTestCase
     protected static final int SHARD_COUNT = 1;
     protected static final int REPLICA_COUNT = 1;
 
+    protected static final String REPLICATION_MISMATCH_VALIDATION_ERROR =
+        "Validation Failed: 1: index setting [index.replication.type] is not allowed to be set as [cluster.index.restrict.replication.type=true];";
+
     @Override
     public Settings indexSettings() {
         return Settings.builder()
@@ -44,14 +57,6 @@ protected boolean addMockInternalEngine() {
         return false;
     }
 
-    @Override
-    protected Settings nodeSettings(int nodeOrdinal) {
-        return Settings.builder()
-            .put(super.nodeSettings(nodeOrdinal))
-            .put(CLUSTER_SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
-            .build();
-    }
-
     public void testIndexReplicationSettingOverridesSegRepClusterSetting() throws Exception {
         Settings settings = Settings.builder().put(CLUSTER_SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT).build();
         final String ANOTHER_INDEX = "test-index";
@@ -123,4 +128,125 @@ public void testIndexReplicationSettingOverridesDocRepClusterSetting() throws Ex
         assertEquals(indicesService.indexService(anotherIndex).getIndexSettings().isSegRepEnabled(), false);
     }
 
+    public void testReplicationTypesOverrideNotAllowed_IndexAPI() {
+        // Generate mutually exclusive replication strategies at cluster and index level
+        List<ReplicationType> replicationStrategies = getRandomReplicationTypesAsList();
+        ReplicationType clusterLevelReplication = replicationStrategies.get(0);
+        ReplicationType indexLevelReplication = replicationStrategies.get(1);
+        Settings nodeSettings = Settings.builder()
+            .put(CLUSTER_SETTING_REPLICATION_TYPE, clusterLevelReplication)
+            .put(CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING.getKey(), true)
+            .build();
+        internalCluster().startClusterManagerOnlyNode(nodeSettings);
+        internalCluster().startDataOnlyNode(nodeSettings);
+        Settings indexSettings = Settings.builder().put(indexSettings()).put(SETTING_REPLICATION_TYPE, indexLevelReplication).build();
+        IllegalArgumentException exception = expectThrows(IllegalArgumentException.class, () -> createIndex(INDEX_NAME, indexSettings));
+        assertEquals(REPLICATION_MISMATCH_VALIDATION_ERROR, exception.getMessage());
+    }
+
+    public void testReplicationTypesOverrideNotAllowed_WithTemplates() {
+        // Generate mutually exclusive replication strategies at cluster and index level
+        List<ReplicationType> replicationStrategies = getRandomReplicationTypesAsList();
+        ReplicationType clusterLevelReplication = replicationStrategies.get(0);
+        ReplicationType templateReplicationType = replicationStrategies.get(1);
+        Settings nodeSettings = Settings.builder()
+            .put(CLUSTER_SETTING_REPLICATION_TYPE, clusterLevelReplication)
+            .put(CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING.getKey(), true)
+            .build();
+        internalCluster().startClusterManagerOnlyNode(nodeSettings);
+        internalCluster().startDataOnlyNode(nodeSettings);
+        internalCluster().startDataOnlyNode(nodeSettings);
+        logger.info(
+            "--> Create index with template replication {} and cluster level replication {}",
+            templateReplicationType,
+            clusterLevelReplication
+        );
+        // Create index template
+        client().admin()
+            .indices()
+            .preparePutTemplate("template_1")
+            .setPatterns(Collections.singletonList("test-idx*"))
+            .setSettings(Settings.builder().put(indexSettings()).put(SETTING_REPLICATION_TYPE, templateReplicationType).build())
+            .setOrder(0)
+            .get();
+
+        GetIndexTemplatesResponse response = client().admin().indices().prepareGetTemplates().get();
+        assertThat(response.getIndexTemplates(), hasSize(1));
+        IllegalArgumentException exception = expectThrows(IllegalArgumentException.class, () -> createIndex(INDEX_NAME));
+        assertEquals(REPLICATION_MISMATCH_VALIDATION_ERROR, exception.getMessage());
+    }
+
+    public void testReplicationTypesOverrideNotAllowed_WithResizeAction() {
+        // Generate mutually exclusive replication strategies at cluster and index level
+        List<ReplicationType> replicationStrategies = getRandomReplicationTypesAsList();
+        ReplicationType clusterLevelReplication = replicationStrategies.get(0);
+        ReplicationType indexLevelReplication = replicationStrategies.get(1);
+        Settings nodeSettings = Settings.builder()
+            .put(CLUSTER_SETTING_REPLICATION_TYPE, clusterLevelReplication)
+            .put(CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING.getKey(), true)
+            .build();
+        internalCluster().startClusterManagerOnlyNode(nodeSettings);
+        internalCluster().startDataOnlyNode(nodeSettings);
+        internalCluster().startDataOnlyNode(nodeSettings);
+        logger.info(
+            "--> Create index with index level replication {} and cluster level replication {}",
+            indexLevelReplication,
+            clusterLevelReplication
+        );
+
+        // Define resize action and target shard count.
+        List<Tuple<ResizeType, Integer>> resizeActionsList = new ArrayList<>();
+        final int initialShardCount = 2;
+        resizeActionsList.add(new Tuple<>(ResizeType.SPLIT, 2 * initialShardCount));
+        resizeActionsList.add(new Tuple<>(ResizeType.SHRINK, SHARD_COUNT));
+        resizeActionsList.add(new Tuple<>(ResizeType.CLONE, initialShardCount));
+
+        Tuple<ResizeType, Integer> resizeActionTuple = resizeActionsList.get(random().nextInt(resizeActionsList.size()));
+        final String targetIndexName = resizeActionTuple.v1().name().toLowerCase(Locale.ROOT) + "-target";
+
+        logger.info("--> Performing resize action {} with shard count {}", resizeActionTuple.v1(), resizeActionTuple.v2());
+
+        Settings indexSettings = Settings.builder()
+            .put(indexSettings())
+            .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, initialShardCount)
+            .put(SETTING_REPLICATION_TYPE, clusterLevelReplication)
+            .build();
+        createIndex(INDEX_NAME, indexSettings);
+
+        // Block writes
+        client().admin().indices().prepareUpdateSettings(INDEX_NAME).setSettings(Settings.builder().put("index.blocks.write", true)).get();
+        ensureGreen();
+
+        // Validate resize action fails
+        IllegalArgumentException exception = expectThrows(
+            IllegalArgumentException.class,
+            () -> client().admin()
+                .indices()
+                .prepareResizeIndex(INDEX_NAME, targetIndexName)
+                .setResizeType(resizeActionTuple.v1())
+                .setSettings(
+                    Settings.builder()
+                        .put("index.number_of_replicas", 0)
+                        .put("index.number_of_shards", resizeActionTuple.v2())
+                        .putNull("index.blocks.write")
+                        .put(SETTING_REPLICATION_TYPE, indexLevelReplication)
+                        .build()
+                )
+                .get()
+        );
+        assertEquals(REPLICATION_MISMATCH_VALIDATION_ERROR, exception.getMessage());
+    }
+
+    /**
+     * Generate a list of ReplicationType with random ordering
+     *
+     * @return List of ReplicationType values
+     */
+    private List<ReplicationType> getRandomReplicationTypesAsList() {
+        List<ReplicationType> replicationStrategies = List.of(ReplicationType.SEGMENT, ReplicationType.DOCUMENT);
+        int randomReplicationIndex = random().nextInt(replicationStrategies.size());
+        ReplicationType clusterLevelReplication = replicationStrategies.get(randomReplicationIndex);
+        ReplicationType indexLevelReplication = replicationStrategies.get(1 - randomReplicationIndex);
+        return List.of(clusterLevelReplication, indexLevelReplication);
+    }
 }

server/src/internalClusterTest/java/org/opensearch/snapshots/SegmentReplicationSnapshotIT.java

@@ -31,6 +31,7 @@
 import java.util.concurrent.TimeUnit;
 
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_REPLICATION_TYPE;
+import static org.opensearch.indices.IndicesService.CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING;
 import static org.opensearch.indices.IndicesService.CLUSTER_SETTING_REPLICATION_TYPE;
 import static org.opensearch.indices.replication.SegmentReplicationBaseIT.waitForSearchableDocs;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
@@ -47,6 +48,9 @@ public class SegmentReplicationSnapshotIT extends AbstractSnapshotIntegTestCase
     private static final String REPOSITORY_NAME = "test-segrep-repo";
     private static final String SNAPSHOT_NAME = "test-segrep-snapshot";
 
+    protected static final String REPLICATION_MISMATCH_VALIDATION_ERROR =
+        "Validation Failed: 1: index setting [index.replication.type] is not allowed to be set as [cluster.index.restrict.replication.type=true];";
+
     public Settings segRepEnableIndexSettings() {
         return getShardSettings().put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT).build();
     }
@@ -306,4 +310,63 @@ public void testSnapshotRestoreOnIndexWithSegRepClusterSetting() throws Exceptio
         IndicesService indicesService = internalCluster().getInstance(IndicesService.class);
         assertEquals(indicesService.indexService(index).getIndexSettings().isSegRepEnabled(), false);
     }
+
+    /**
+    * 1. Create index in DOCUMENT replication type
+    * 2. Snapshot index
+    * 3. Add new set of nodes with `cluster.indices.replication.strategy` set to SEGMENT and `cluster.index.restrict.replication.type`
+    *    set to true.
+    * 4. Perform restore on new set of nodes to validate restored index has `DOCUMENT` replication.
+    */
+    public void testSnapshotRestoreOnRestrictReplicationSetting() throws Exception {
+        final int documentCount = scaledRandomIntBetween(1, 10);
+        String originalClusterManagerNode = internalCluster().startClusterManagerOnlyNode();
+
+        // Starting two nodes with primary and replica shards respectively.
+        final String primaryNode = internalCluster().startDataOnlyNode();
+        prepareCreate(
+            INDEX_NAME,
+            Settings.builder()
+                // we want to override cluster replication setting by passing a index replication setting
+                .put(IndexMetadata.SETTING_REPLICATION_TYPE, ReplicationType.DOCUMENT)
+                .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, REPLICA_COUNT)
+                .put(IndexMetadata.SETTING_NUMBER_OF_SHARDS, SHARD_COUNT)
+        ).get();
+        ensureYellowAndNoInitializingShards(INDEX_NAME);
+        final String replicaNode = internalCluster().startDataOnlyNode();
+        ensureGreen(INDEX_NAME);
+
+        for (int i = 0; i < documentCount; i++) {
+            client().prepareIndex(INDEX_NAME).setId(String.valueOf(i)).setSource("foo", "bar").get();
+        }
+
+        createSnapshot();
+
+        // Delete index
+        assertAcked(client().admin().indices().delete(new DeleteIndexRequest(INDEX_NAME)).get());
+        assertFalse("index [" + INDEX_NAME + "] should have been deleted", indexExists(INDEX_NAME));
+
+        // Start new set of nodes with cluster level replication type setting and restrict replication type setting.
+        Settings settings = Settings.builder()
+            .put(CLUSTER_SETTING_REPLICATION_TYPE, ReplicationType.SEGMENT)
+            .put(CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING.getKey(), true)
+            .build();
+
+        // Start new cluster manager node
+        String newClusterManagerNode = internalCluster().startClusterManagerOnlyNode(settings);
+
+        // Remove older nodes
+        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(originalClusterManagerNode));
+        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(primaryNode));
+        internalCluster().stopRandomNode(InternalTestCluster.nameFilter(replicaNode));
+
+        String newPrimaryNode = internalCluster().startDataOnlyNode(settings);
+        String newReplicaNode = internalCluster().startDataOnlyNode(settings);
+
+        // Perform snapshot restore
+        logger.info("--> Performing snapshot restore to target index");
+
+        IllegalArgumentException exception = expectThrows(IllegalArgumentException.class, () -> restoreSnapshotWithSettings(null));
+        assertEquals(REPLICATION_MISMATCH_VALIDATION_ERROR, exception.getMessage());
+    }
 }

server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateIndexService.java

@@ -907,6 +907,10 @@ static Settings aggregateIndexSettings(
             );
         }
 
+        List<String> validationErrors = new ArrayList<>();
+        validateIndexReplicationTypeSettings(indexSettingsBuilder.build(), clusterSettings).ifPresent(validationErrors::add);
+        validateErrors(request.index(), validationErrors);
+
         Settings indexSettings = indexSettingsBuilder.build();
         /*
          * We can not validate settings until we have applied templates, otherwise we do not know the actual settings
@@ -1246,7 +1250,11 @@ private void validate(CreateIndexClusterStateUpdateRequest request, ClusterState
     public void validateIndexSettings(String indexName, final Settings settings, final boolean forbidPrivateIndexSettings)
         throws IndexCreationException {
         List<String> validationErrors = getIndexSettingsValidationErrors(settings, forbidPrivateIndexSettings, indexName);
+        validateIndexReplicationTypeSettings(settings, clusterService.getClusterSettings()).ifPresent(validationErrors::add);
+        validateErrors(indexName, validationErrors);
+    }
 
+    private static void validateErrors(String indexName, List<String> validationErrors) {
         if (validationErrors.isEmpty() == false) {
             ValidationException validationException = new ValidationException();
             validationException.addValidationErrors(validationErrors);
@@ -1322,6 +1330,27 @@ private static List<String> validateIndexCustomPath(Settings settings, @Nullable
         return validationErrors;
     }
 
+    /**
+     * Validates {@code index.replication.type} is matches with cluster level setting {@code cluster.indices.replication.strategy}
+     * when {@code cluster.index.restrict.replication.type} is set to true.
+     *
+     * @param requestSettings settings passed in during index create request
+     * @param clusterSettings cluster setting
+     */
+    private static Optional<String> validateIndexReplicationTypeSettings(Settings requestSettings, ClusterSettings clusterSettings) {
+        if (clusterSettings.get(IndicesService.CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING)
+            && requestSettings.hasValue(SETTING_REPLICATION_TYPE)
+            && requestSettings.get(INDEX_REPLICATION_TYPE_SETTING.getKey())
+                .equals(clusterSettings.get(CLUSTER_REPLICATION_TYPE_SETTING).name()) == false) {
+            return Optional.of(
+                "index setting [index.replication.type] is not allowed to be set as ["
+                    + IndicesService.CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING.getKey()
+                    + "=true]"
+            );
+        }
+        return Optional.empty();
+    }
+
     /**
      * Validates the settings and mappings for shrinking an index.
      *

server/src/main/java/org/opensearch/common/settings/ClusterSettings.java

@@ -701,7 +701,8 @@ public void apply(Settings value, Settings current, Settings previous) {
                 AdmissionControlSettings.ADMISSION_CONTROL_TRANSPORT_LAYER_MODE,
                 CpuBasedAdmissionControllerSettings.CPU_BASED_ADMISSION_CONTROLLER_TRANSPORT_LAYER_MODE,
                 CpuBasedAdmissionControllerSettings.INDEXING_CPU_USAGE_LIMIT,
-                CpuBasedAdmissionControllerSettings.SEARCH_CPU_USAGE_LIMIT
+                CpuBasedAdmissionControllerSettings.SEARCH_CPU_USAGE_LIMIT,
+                IndicesService.CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING
             )
         )
     );

server/src/main/java/org/opensearch/indices/IndicesService.java

@@ -301,6 +301,19 @@ public class IndicesService extends AbstractLifecycleComponent
         Property.Final
     );
 
+    /**
+     * If enabled, this setting enforces that indexes will be created with a replication type matching the cluster setting
+     * defined in cluster.indices.replication.strategy by rejecting any request that specifies a replication type that
+     * does not match the cluster setting. If disabled, a user can choose a replication type on a per-index basis using
+     * the index.replication.type setting.
+     */
+    public static final Setting<Boolean> CLUSTER_INDEX_RESTRICT_REPLICATION_TYPE_SETTING = Setting.boolSetting(
+        "cluster.index.restrict.replication.type",
+        false,
+        Property.NodeScope,
+        Property.Final
+    );
+
     /**
      * The node's settings.
      */