Hashed prefix for index metadata

Signed-off-by: Sooraj Sinha <soosinha@amazon.com>

server/src/main/java/org/opensearch/common/remote/RemoteWriteableBlobEntity.java

@@ -63,6 +63,10 @@ public String[] getBlobPathTokens() {
 
     public abstract String generateBlobFileName();
 
+    public BlobPath getPrefixedPath(BlobPath blobPath) {
+        return blobPath;
+    }
+
     public String clusterUUID() {
         return clusterUUID;
     }

server/src/main/java/org/opensearch/common/remote/RemoteWriteableEntityBlobStore.java

@@ -97,12 +97,14 @@ public BlobPath getBlobPathPrefix(String clusterUUID) {
         return blobStoreRepository.basePath().add(encodeString(getClusterName())).add(pathToken).add(clusterUUID);
     }
 
+
+
     public BlobPath getBlobPathForUpload(final RemoteWriteableBlobEntity<T> obj) {
         BlobPath blobPath = getBlobPathPrefix(obj.clusterUUID());
         for (String token : obj.getBlobPathParameters().getPathTokens()) {
             blobPath = blobPath.add(token);
         }
-        return blobPath;
+        return obj.getPrefixedPath(blobPath);
     }
 
     public BlobPath getBlobPathForDownload(final RemoteWriteableBlobEntity<T> obj) {

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

@@ -107,6 +107,7 @@
 import org.opensearch.gateway.ShardsBatchGatewayAllocator;
 import org.opensearch.gateway.remote.RemoteClusterStateCleanupManager;
 import org.opensearch.gateway.remote.RemoteClusterStateService;
+import org.opensearch.gateway.remote.RemoteIndexMetadataManager;
 import org.opensearch.gateway.remote.model.RemoteRoutingTableBlobStore;
 import org.opensearch.http.HttpTransportSettings;
 import org.opensearch.index.IndexModule;
@@ -730,6 +731,8 @@ public void apply(Settings value, Settings current, Settings previous) {
                 GLOBAL_METADATA_UPLOAD_TIMEOUT_SETTING,
                 METADATA_MANIFEST_UPLOAD_TIMEOUT_SETTING,
                 RemoteClusterStateService.REMOTE_STATE_READ_TIMEOUT_SETTING,
+                RemoteIndexMetadataManager.REMOTE_INDEX_METADATA_PATH_TYPE_SETTING,
+                RemoteIndexMetadataManager.REMOTE_INDEX_METADATA_PATH_HASH_ALGO_SETTING,
                 RemoteStoreNodeService.REMOTE_STORE_COMPATIBILITY_MODE_SETTING,
                 RemoteStoreNodeService.MIGRATION_DIRECTION_SETTING,
                 IndicesService.CLUSTER_REMOTE_INDEX_RESTRICT_ASYNC_DURABILITY_SETTING,

server/src/main/java/org/opensearch/gateway/remote/RemoteClusterStateService.java

@@ -659,7 +659,9 @@ UploadedMetadataResults writeMetadataInParallel(
                     indexMetadata,
                     clusterState.metadata().clusterUUID(),
                     blobStoreRepository.getCompressor(),
-                    blobStoreRepository.getNamedXContentRegistry()
+                    blobStoreRepository.getNamedXContentRegistry(),
+                    remoteIndexMetadataManager.getPathTypeSetting(),
+                    remoteIndexMetadataManager.getPathHashAlgoSetting()
                 ),
                 listener
             );

server/src/main/java/org/opensearch/gateway/remote/RemoteIndexMetadataManager.java

@@ -20,6 +20,7 @@
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.gateway.remote.model.RemoteIndexMetadata;
 import org.opensearch.gateway.remote.model.RemoteReadResult;
+import org.opensearch.index.remote.RemoteStoreEnums;
 import org.opensearch.index.translog.transfer.BlobStoreTransferService;
 import org.opensearch.repositories.blobstore.BlobStoreRepository;
 import org.opensearch.threadpool.ThreadPool;
@@ -44,11 +45,38 @@ public class RemoteIndexMetadataManager extends AbstractRemoteWritableEntityMana
         Setting.Property.Deprecated
     );
 
+    /**
+     * This setting is used to set the remote index metadata blob store path type strategy.
+     */
+    public static final Setting<RemoteStoreEnums.PathType> REMOTE_INDEX_METADATA_PATH_TYPE_SETTING = new Setting<>(
+        "cluster.remote_store.index_metadata.path_type",
+        RemoteStoreEnums.PathType.HASHED_PREFIX.toString(),
+        RemoteStoreEnums.PathType::parseString,
+        Setting.Property.NodeScope,
+        Setting.Property.Dynamic
+    );
+
+    /**
+     * This setting is used to set the remote index metadata blob store path hash algorithm strategy.
+     * This setting will come to effect if the {@link #REMOTE_INDEX_METADATA_PATH_TYPE_SETTING}
+     * is either {@code HASHED_PREFIX} or {@code HASHED_INFIX}.
+     */
+    public static final Setting<RemoteStoreEnums.PathHashAlgorithm> REMOTE_INDEX_METADATA_PATH_HASH_ALGO_SETTING = new Setting<>(
+        "cluster.remote_store.index_metadata.path_hash_algo",
+        RemoteStoreEnums.PathHashAlgorithm.FNV_1A_BASE64.toString(),
+        RemoteStoreEnums.PathHashAlgorithm::parseString,
+        Setting.Property.NodeScope,
+        Setting.Property.Dynamic
+    );
+
     private final Compressor compressor;
     private final NamedXContentRegistry namedXContentRegistry;
 
     private volatile TimeValue indexMetadataUploadTimeout;
 
+    private RemoteStoreEnums.PathType pathType;
+    private RemoteStoreEnums.PathHashAlgorithm pathHashAlgo;
+
     public RemoteIndexMetadataManager(
         ClusterSettings clusterSettings,
         String clusterName,
@@ -70,7 +98,11 @@ public RemoteIndexMetadataManager(
         this.namedXContentRegistry = blobStoreRepository.getNamedXContentRegistry();
         this.compressor = blobStoreRepository.getCompressor();
         this.indexMetadataUploadTimeout = clusterSettings.get(INDEX_METADATA_UPLOAD_TIMEOUT_SETTING);
+        this.pathType = clusterSettings.get(REMOTE_INDEX_METADATA_PATH_TYPE_SETTING);
+        this.pathHashAlgo = clusterSettings.get(REMOTE_INDEX_METADATA_PATH_HASH_ALGO_SETTING);
         clusterSettings.addSettingsUpdateConsumer(INDEX_METADATA_UPLOAD_TIMEOUT_SETTING, this::setIndexMetadataUploadTimeout);
+        clusterSettings.addSettingsUpdateConsumer(REMOTE_INDEX_METADATA_PATH_TYPE_SETTING, this::setPathTypeSetting);
+        clusterSettings.addSettingsUpdateConsumer(REMOTE_INDEX_METADATA_PATH_HASH_ALGO_SETTING, this::setPathHashAlgoSetting);
     }
 
     /**
@@ -127,4 +159,20 @@ protected ActionListener<Object> getWrappedReadListener(
             ex -> listener.onFailure(new RemoteStateTransferException("Download failed for " + component, remoteEntity, ex))
         );
     }
+
+    private void setPathTypeSetting(RemoteStoreEnums.PathType pathType) {
+        this.pathType = pathType;
+    }
+
+    private void setPathHashAlgoSetting(RemoteStoreEnums.PathHashAlgorithm pathHashAlgo) {
+        this.pathHashAlgo = pathHashAlgo;
+    }
+
+    protected RemoteStoreEnums.PathType getPathTypeSetting() {
+        return pathType;
+    }
+
+    protected RemoteStoreEnums.PathHashAlgorithm getPathHashAlgoSetting() {
+        return pathHashAlgo;
+    }
 }

server/src/main/java/org/opensearch/gateway/remote/model/RemoteIndexMetadata.java

@@ -9,6 +9,7 @@
 package org.opensearch.gateway.remote.model;
 
 import org.opensearch.cluster.metadata.IndexMetadata;
+import org.opensearch.common.blobstore.BlobPath;
 import org.opensearch.common.io.Streams;
 import org.opensearch.common.remote.AbstractClusterMetadataWriteableBlobEntity;
 import org.opensearch.common.remote.BlobPathParameters;
@@ -17,6 +18,9 @@
 import org.opensearch.gateway.remote.ClusterMetadataManifest.UploadedIndexMetadata;
 import org.opensearch.gateway.remote.ClusterMetadataManifest.UploadedMetadata;
 import org.opensearch.gateway.remote.RemoteClusterStateUtils;
+import org.opensearch.index.remote.RemoteStoreEnums;
+import org.opensearch.index.remote.RemoteStoreEnums.PathHashAlgorithm;
+import org.opensearch.index.remote.RemoteStorePathStrategy;
 import org.opensearch.index.remote.RemoteStoreUtils;
 import org.opensearch.repositories.blobstore.ChecksumBlobStoreFormat;
 
@@ -41,6 +45,21 @@ public class RemoteIndexMetadata extends AbstractClusterMetadataWriteableBlobEnt
     public static final String INDEX = "index";
 
     private IndexMetadata indexMetadata;
+    private RemoteStoreEnums.PathType pathType;
+    private RemoteStoreEnums.PathHashAlgorithm pathHashAlgo;
+
+    public RemoteIndexMetadata(
+        final IndexMetadata indexMetadata,
+        final String clusterUUID,
+        final Compressor compressor,
+        final NamedXContentRegistry namedXContentRegistry,
+        final RemoteStoreEnums.PathType pathType,
+        final RemoteStoreEnums.PathHashAlgorithm pathHashAlgo
+    ) {
+        this(indexMetadata, clusterUUID, compressor, namedXContentRegistry);
+        this.pathType = pathType;
+        this.pathHashAlgo = pathHashAlgo;
+    }
 
     public RemoteIndexMetadata(
         final IndexMetadata indexMetadata,
@@ -86,6 +105,18 @@ public String generateBlobFileName() {
         return blobFileName;
     }
 
+    @Override
+    public BlobPath getPrefixedPath(BlobPath blobPath) {
+        if (pathType == null) {
+            return blobPath;
+        }
+        assert pathHashAlgo != null;
+        return pathType.path(
+            RemoteStorePathStrategy.PathInput.builder().basePath(blobPath).indexUUID(indexMetadata.getIndexUUID()).build(),
+            pathHashAlgo
+        );
+    }
+
     @Override
     public UploadedMetadata getUploadedMetadata() {
         assert blobName != null;

server/src/test/java/org/opensearch/gateway/remote/RemoteIndexMetadataManagerTests.java

@@ -26,6 +26,7 @@
 import org.opensearch.core.compress.NoneCompressor;
 import org.opensearch.gateway.remote.model.RemoteIndexMetadata;
 import org.opensearch.gateway.remote.model.RemoteReadResult;
+import org.opensearch.index.remote.RemoteStoreEnums;
 import org.opensearch.index.remote.RemoteStoreUtils;
 import org.opensearch.index.translog.transfer.BlobStoreTransferService;
 import org.opensearch.repositories.blobstore.BlobStoreRepository;
@@ -51,18 +52,21 @@
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
+import static org.opensearch.index.remote.RemoteStoreEnums.PathHashAlgorithm.FNV_1A_BASE64;
+import static org.opensearch.index.remote.RemoteStoreEnums.PathType.HASHED_PREFIX;
 
 public class RemoteIndexMetadataManagerTests extends OpenSearchTestCase {
 
     private RemoteIndexMetadataManager remoteIndexMetadataManager;
     private BlobStoreRepository blobStoreRepository;
     private BlobStoreTransferService blobStoreTransferService;
     private Compressor compressor;
+    private ClusterSettings clusterSettings;
     private final ThreadPool threadPool = new TestThreadPool(getClass().getName());
 
     @Before
     public void setup() {
-        ClusterSettings clusterSettings = new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
+        clusterSettings = new ClusterSettings(Settings.EMPTY, ClusterSettings.BUILT_IN_CLUSTER_SETTINGS);
         blobStoreRepository = mock(BlobStoreRepository.class);
         BlobPath blobPath = new BlobPath().add("random-path");
         when((blobStoreRepository.basePath())).thenReturn(blobPath);
@@ -182,6 +186,31 @@ public void testGetAsyncReadRunnable_IOFailure() throws Exception {
         assertTrue(listener.getFailure() instanceof RemoteStateTransferException);
     }
 
+    public void testRemoteRoutingTablePathTypeSetting() {
+        // Assert the default is HASHED_PREFIX
+        assertEquals(HASHED_PREFIX.toString(), remoteIndexMetadataManager.getPathTypeSetting().toString());
+
+        Settings newSettings = Settings.builder()
+            .put("cluster.remote_store.index_metadata.path_type", RemoteStoreEnums.PathType.FIXED.toString())
+            .build();
+        clusterSettings.applySettings(newSettings);
+        assertEquals(RemoteStoreEnums.PathType.FIXED.toString(), remoteIndexMetadataManager.getPathTypeSetting().toString());
+    }
+
+    public void testRemoteRoutingTableHashAlgoSetting() {
+        // Assert the default is FNV_1A_BASE64
+        assertEquals(FNV_1A_BASE64.toString(), remoteIndexMetadataManager.getPathHashAlgoSetting().toString());
+
+        Settings newSettings = Settings.builder()
+            .put("cluster.remote_store.index_metadata.path_hash_algo", RemoteStoreEnums.PathHashAlgorithm.FNV_1A_COMPOSITE_1.toString())
+            .build();
+        clusterSettings.applySettings(newSettings);
+        assertEquals(
+            RemoteStoreEnums.PathHashAlgorithm.FNV_1A_COMPOSITE_1.toString(),
+            remoteIndexMetadataManager.getPathHashAlgoSetting().toString()
+        );
+    }
+
     private IndexMetadata getIndexMetadata(String name, @Nullable Boolean writeIndex, String... aliases) {
         IndexMetadata.Builder builder = IndexMetadata.builder(name)
             .settings(

server/src/test/java/org/opensearch/gateway/remote/model/RemoteIndexMetadataTests.java

@@ -23,6 +23,9 @@
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.gateway.remote.ClusterMetadataManifest.UploadedMetadata;
 import org.opensearch.gateway.remote.RemoteClusterStateUtils;
+import org.opensearch.index.remote.RemoteStoreEnums;
+import org.opensearch.index.remote.RemoteStoreEnums.PathHashAlgorithm;
+import org.opensearch.index.remote.RemoteStoreEnums.PathType;
 import org.opensearch.index.remote.RemoteStoreUtils;
 import org.opensearch.index.translog.transfer.BlobStoreTransferService;
 import org.opensearch.indices.IndicesModule;
@@ -171,6 +174,18 @@ public void testSerDe() throws IOException {
         }
     }
 
+    public void testPrefixedPath() {
+        IndexMetadata indexMetadata = getIndexMetadata();
+        RemoteIndexMetadata remoteObjectForUpload = new RemoteIndexMetadata(indexMetadata, clusterUUID, compressor, namedXContentRegistry,
+            PathType.HASHED_PREFIX, PathHashAlgorithm.FNV_1A_COMPOSITE_1
+        );
+        String testPath = "test-path";
+        String expectedPath = "410100110100101/test-path/index-uuid/";
+        BlobPath prefixedPath = remoteObjectForUpload.getPrefixedPath(BlobPath.cleanPath().add(testPath));
+        assertThat(prefixedPath.buildAsString(), is(expectedPath));
+
+    }
+
     private IndexMetadata getIndexMetadata() {
         final Index index = new Index("test-index", "index-uuid");
         final Settings idxSettings = Settings.builder()