[Remote Store] Deletion of Remote Segments and Translog upon Index De…

…letion (opensearch-project#7682)

Signed-off-by: Gaurav Bafna <gbbafna@amazon.com>
Signed-off-by: Shivansh Arora <hishiv@amazon.com>

server/src/internalClusterTest/java/org/opensearch/index/shard/GlobalCheckpointListenersIT.java

@@ -126,7 +126,7 @@ public void accept(final long g, final Exception e) {
             }
 
         }, null);
-        shard.close("closed", randomBoolean());
+        shard.close("closed", randomBoolean(), false);
         assertBusy(() -> assertTrue(invoked.get()));
     }
 

server/src/internalClusterTest/java/org/opensearch/index/shard/IndexShardIT.java

@@ -620,7 +620,7 @@ public void testShardHasMemoryBufferOnTranslogRecover() throws Throwable {
         client().prepareIndex("test").setId("1").setSource("{\"foo\" : \"bar\"}", XContentType.JSON).setRefreshPolicy(IMMEDIATE).get();
 
         CheckedFunction<DirectoryReader, DirectoryReader, IOException> wrapper = directoryReader -> directoryReader;
-        shard.close("simon says", false);
+        shard.close("simon says", false, false);
         AtomicReference<IndexShard> shardRef = new AtomicReference<>();
         List<Exception> failures = new ArrayList<>();
         IndexingOperationListener listener = new IndexingOperationListener() {
@@ -658,7 +658,7 @@ public void postDelete(ShardId shardId, Engine.Delete delete, Engine.DeleteResul
         try {
             ExceptionsHelper.rethrowAndSuppress(failures);
         } finally {
-            newShard.close("just do it", randomBoolean());
+            newShard.close("just do it", randomBoolean(), false);
         }
     }
 

server/src/internalClusterTest/java/org/opensearch/remotestore/RemoteStoreBaseIntegTestCase.java

@@ -18,7 +18,13 @@
 import org.opensearch.indices.replication.common.ReplicationType;
 import org.opensearch.test.OpenSearchIntegTestCase;
 
+import java.io.IOException;
+import java.nio.file.FileVisitResult;
+import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.SimpleFileVisitor;
+import java.nio.file.attribute.BasicFileAttributes;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
 
@@ -27,6 +33,8 @@ public class RemoteStoreBaseIntegTestCase extends OpenSearchIntegTestCase {
     protected static final int SHARD_COUNT = 1;
     protected static final int REPLICA_COUNT = 1;
 
+    protected Path absolutePath;
+
     @Override
     protected boolean addMockInternalEngine() {
         return false;
@@ -73,7 +81,7 @@ protected Settings remoteTranslogIndexSettings(int numberOfReplicas) {
     @Before
     public void setup() {
         internalCluster().startClusterManagerOnlyNode();
-        Path absolutePath = randomRepoPath().toAbsolutePath();
+        absolutePath = randomRepoPath().toAbsolutePath();
         assertAcked(
             clusterAdmin().preparePutRepository(REPOSITORY_NAME).setType("fs").setSettings(Settings.builder().put("location", absolutePath))
         );
@@ -84,4 +92,22 @@ public void teardown() {
         assertAcked(clusterAdmin().prepareDeleteRepository(REPOSITORY_NAME));
     }
 
+    public int getFileCount(Path path) throws Exception {
+        final AtomicInteger filesExisting = new AtomicInteger(0);
+        Files.walkFileTree(path, new SimpleFileVisitor<>() {
+            @Override
+            public FileVisitResult postVisitDirectory(Path dir, IOException impossible) throws IOException {
+                return FileVisitResult.CONTINUE;
+            }
+
+            @Override
+            public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
+                filesExisting.incrementAndGet();
+                return FileVisitResult.CONTINUE;
+            }
+        });
+
+        return filesExisting.get();
+    }
+
 }

server/src/internalClusterTest/java/org/opensearch/remotestore/RemoteStoreIT.java

@@ -9,6 +9,7 @@
 package org.opensearch.remotestore;
 
 import org.opensearch.action.admin.cluster.remotestore.restore.RestoreRemoteStoreRequest;
+import org.opensearch.action.admin.indices.delete.DeleteIndexRequest;
 import org.opensearch.action.admin.indices.recovery.RecoveryResponse;
 import org.opensearch.action.index.IndexResponse;
 import org.opensearch.action.support.PlainActionFuture;
@@ -23,13 +24,15 @@
 import org.opensearch.test.transport.MockTransportService;
 
 import java.io.IOException;
+import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 
+import static org.hamcrest.Matchers.comparesEqualTo;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 
@@ -241,4 +244,37 @@ public void testPeerRecoveryWithRemoteStoreAndRemoteTranslogNoDataRefresh() thro
     public void testPeerRecoveryWithRemoteStoreAndRemoteTranslogRefresh() throws Exception {
         testPeerRecovery(true, randomIntBetween(2, 5), false);
     }
+
+    private void verifyRemoteStoreCleanup(boolean remoteTranslog) throws Exception {
+        internalCluster().startDataOnlyNodes(3);
+        if (remoteTranslog) {
+            createIndex(INDEX_NAME, remoteTranslogIndexSettings(1));
+        } else {
+            createIndex(INDEX_NAME, remoteStoreIndexSettings(1));
+        }
+
+        indexData(5, randomBoolean());
+        String indexUUID = client().admin()
+            .indices()
+            .prepareGetSettings(INDEX_NAME)
+            .get()
+            .getSetting(INDEX_NAME, IndexMetadata.SETTING_INDEX_UUID);
+        Path indexPath = Path.of(String.valueOf(absolutePath), indexUUID);
+        assertTrue(getFileCount(indexPath) > 0);
+        assertAcked(client().admin().indices().delete(new DeleteIndexRequest(INDEX_NAME)).get());
+        // Delete is async. Give time for it
+        assertBusy(() -> {
+            try {
+                assertThat(getFileCount(indexPath), comparesEqualTo(0));
+            } catch (Exception e) {}
+        }, 30, TimeUnit.SECONDS);
+    }
+
+    public void testRemoteSegmentCleanup() throws Exception {
+        verifyRemoteStoreCleanup(false);
+    }
+
+    public void testRemoteTranslogCleanup() throws Exception {
+        verifyRemoteStoreCleanup(true);
+    }
 }

server/src/main/java/org/opensearch/index/IndexService.java

@@ -603,6 +603,7 @@ public synchronized void removeShard(int shardId, String reason) {
     private void closeShard(String reason, ShardId sId, IndexShard indexShard, Store store, IndexEventListener listener) {
         final int shardId = sId.id();
         final Settings indexSettings = this.getIndexSettings().getSettings();
+        Store remoteStore = indexShard.remoteStore();
         if (store != null) {
             store.beforeClose();
         }
@@ -616,7 +617,7 @@ private void closeShard(String reason, ShardId sId, IndexShard indexShard, Store
                     try {
                         // only flush if we are closed (closed index or shutdown) and if we are not deleted
                         final boolean flushEngine = deleted.get() == false && closed.get();
-                        indexShard.close(reason, flushEngine);
+                        indexShard.close(reason, flushEngine, deleted.get());
                     } catch (Exception e) {
                         logger.debug(() -> new ParameterizedMessage("[{}] failed to close index shard", shardId), e);
                         // ignore
@@ -632,6 +633,11 @@ private void closeShard(String reason, ShardId sId, IndexShard indexShard, Store
                 } else {
                     logger.trace("[{}] store not initialized prior to closing shard, nothing to close", shardId);
                 }
+
+                if (remoteStore != null && indexShard.isPrimaryMode() && deleted.get()) {
+                    remoteStore.close();
+                }
+
             } catch (Exception e) {
                 logger.warn(
                     () -> new ParameterizedMessage("[{}] failed to close store on shard removal (reason: [{}])", shardId, reason),

server/src/main/java/org/opensearch/index/shard/IndexShard.java

@@ -1882,7 +1882,7 @@ public CacheHelper getReaderCacheHelper() {
 
     }
 
-    public void close(String reason, boolean flushEngine) throws IOException {
+    public void close(String reason, boolean flushEngine, boolean deleted) throws IOException {
         synchronized (engineMutex) {
             try {
                 synchronized (mutex) {
@@ -1898,12 +1898,30 @@ public void close(String reason, boolean flushEngine) throws IOException {
                     // playing safe here and close the engine even if the above succeeds - close can be called multiple times
                     // Also closing refreshListeners to prevent us from accumulating any more listeners
                     IOUtils.close(engine, globalCheckpointListeners, refreshListeners, pendingReplicationActions);
+
+                    if (deleted && engine != null && isPrimaryMode()) {
+                        // Translog Clean up
+                        engine.translogManager().onDelete();
+                    }
+
                     indexShardOperationPermits.close();
                 }
             }
         }
     }
 
+    /*
+    ToDo : Fix this https://github.com/opensearch-project/OpenSearch/issues/8003
+     */
+    private RemoteSegmentStoreDirectory getRemoteDirectory() {
+        assert indexSettings.isRemoteStoreEnabled();
+        assert remoteStore.directory() instanceof FilterDirectory : "Store.directory is not an instance of FilterDirectory";
+        FilterDirectory remoteStoreDirectory = (FilterDirectory) remoteStore.directory();
+        FilterDirectory byteSizeCachingStoreDirectory = (FilterDirectory) remoteStoreDirectory.getDelegate();
+        final Directory remoteDirectory = byteSizeCachingStoreDirectory.getDelegate();
+        return ((RemoteSegmentStoreDirectory) remoteDirectory);
+    }
+
     public void preRecovery() {
         final IndexShardState currentState = this.state; // single volatile read
         if (currentState == IndexShardState.CLOSED) {
@@ -4520,16 +4538,10 @@ public void syncSegmentsFromRemoteSegmentStore(boolean overrideLocal, boolean re
         throws IOException {
         assert indexSettings.isRemoteStoreEnabled();
         logger.info("Downloading segments from remote segment store");
-        assert remoteStore.directory() instanceof FilterDirectory : "Store.directory is not an instance of FilterDirectory";
-        FilterDirectory remoteStoreDirectory = (FilterDirectory) remoteStore.directory();
-        assert remoteStoreDirectory.getDelegate() instanceof FilterDirectory
-            : "Store.directory is not enclosing an instance of FilterDirectory";
-        FilterDirectory byteSizeCachingStoreDirectory = (FilterDirectory) remoteStoreDirectory.getDelegate();
-        final Directory remoteDirectory = byteSizeCachingStoreDirectory.getDelegate();
+        RemoteSegmentStoreDirectory remoteDirectory = getRemoteDirectory();
         // We need to call RemoteSegmentStoreDirectory.init() in order to get latest metadata of the files that
         // are uploaded to the remote segment store.
-        assert remoteDirectory instanceof RemoteSegmentStoreDirectory : "remoteDirectory is not an instance of RemoteSegmentStoreDirectory";
-        RemoteSegmentMetadata remoteSegmentMetadata = ((RemoteSegmentStoreDirectory) remoteDirectory).init();
+        RemoteSegmentMetadata remoteSegmentMetadata = remoteDirectory.init();
         Map<String, RemoteSegmentStoreDirectory.UploadedSegmentMetadata> uploadedSegments = ((RemoteSegmentStoreDirectory) remoteDirectory)
             .getSegmentsUploadedToRemoteStore();
         store.incRef();

server/src/main/java/org/opensearch/index/store/RemoteDirectory.java

@@ -210,4 +210,8 @@ public void rename(String source, String dest) throws IOException {
     public Lock obtainLock(String name) throws IOException {
         throw new UnsupportedOperationException();
     }
+
+    public void delete() throws IOException {
+        blobContainer.delete();
+    }
 }

server/src/main/java/org/opensearch/index/store/RemoteSegmentStoreDirectory.java

@@ -20,24 +20,24 @@
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.opensearch.common.UUIDs;
+import org.opensearch.common.io.VersionedCodecStreamWrapper;
 import org.opensearch.common.lucene.store.ByteArrayIndexInput;
+import org.opensearch.index.store.lockmanager.FileLockInfo;
 import org.opensearch.index.store.lockmanager.RemoteStoreCommitLevelLockManager;
 import org.opensearch.index.store.lockmanager.RemoteStoreLockManager;
-import org.opensearch.index.store.lockmanager.FileLockInfo;
 import org.opensearch.index.store.remote.metadata.RemoteSegmentMetadata;
-import org.opensearch.common.io.VersionedCodecStreamWrapper;
 import org.opensearch.index.store.remote.metadata.RemoteSegmentMetadataHandler;
 
 import java.io.IOException;
 import java.nio.file.NoSuchFileException;
-import java.util.Map;
-import java.util.HashSet;
-import java.util.Optional;
-import java.util.HashMap;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -617,4 +617,32 @@ public void deleteStaleSegments(int lastNMetadataFilesToKeep) throws IOException
             }
         }
     }
+
+    /*
+    Tries to delete shard level directory if it is empty
+    Return true if it deleted it successfully
+     */
+    private boolean deleteIfEmpty() throws IOException {
+        Collection<String> metadataFiles = remoteMetadataDirectory.listFilesByPrefix(MetadataFilenameUtils.METADATA_PREFIX);
+        if (metadataFiles.size() != 0) {
+            logger.info("Remote directory still has files , not deleting the path");
+            return false;
+        }
+
+        try {
+            remoteDataDirectory.delete();
+            remoteMetadataDirectory.delete();
+            mdLockManager.delete();
+        } catch (Exception e) {
+            logger.error("Exception occurred while deleting directory", e);
+            return false;
+        }
+
+        return true;
+    }
+
+    public void close() throws IOException {
+        deleteStaleSegments(0);
+        deleteIfEmpty();
+    }
 }

server/src/main/java/org/opensearch/index/store/lockmanager/RemoteStoreLockManager.java

@@ -22,7 +22,7 @@ public interface RemoteStoreLockManager {
      * @param lockInfo lock info instance for which we need to acquire lock.
      * @throws IOException throws exception in case there is a problem with acquiring lock.
      */
-    public void acquire(LockInfo lockInfo) throws IOException;
+    void acquire(LockInfo lockInfo) throws IOException;
 
     /**
      *
@@ -38,4 +38,9 @@ public interface RemoteStoreLockManager {
      * @throws IOException throws exception in case there is a problem in checking if a given file is locked or not.
      */
     Boolean isAcquired(LockInfo lockInfo) throws IOException;
+
+    /*
+    Deletes all lock related files and directories
+     */
+    void delete() throws IOException;
 }

server/src/main/java/org/opensearch/index/store/lockmanager/RemoteStoreMetadataLockManager.java

@@ -83,4 +83,8 @@ public Boolean isAcquired(LockInfo lockInfo) throws IOException {
         Collection<String> lockFiles = lockDirectory.listFilesByPrefix(((FileLockInfo) lockInfo).getLockPrefix());
         return !lockFiles.isEmpty();
     }
+
+    public void delete() throws IOException {
+        lockDirectory.delete();
+    }
 }

server/src/main/java/org/opensearch/index/translog/InternalTranslogManager.java

@@ -296,6 +296,10 @@ public void setMinSeqNoToKeep(long seqNo) {
         translog.setMinSeqNoToKeep(seqNo);
     }
 
+    public void onDelete() {
+        translog.onDelete();
+    }
+
     /**
      * Reads operations from the translog
      * @param location location of translog

server/src/main/java/org/opensearch/index/translog/NoOpTranslogManager.java

@@ -120,4 +120,6 @@ public Translog.Location add(Translog.Operation operation) throws IOException {
     public Translog.Snapshot newChangesSnapshot(long fromSeqNo, long toSeqNo, boolean requiredFullRange) throws IOException {
         throw new UnsupportedOperationException("Translog snapshot unsupported with no-op translogs");
     }
+
+    public void onDelete() {}
 }

server/src/main/java/org/opensearch/index/translog/RemoteFsTranslog.java

@@ -422,4 +422,14 @@ private void deleteStaleRemotePrimaryTermsAndMetadataFiles() {
             translogTransferManager.deleteStaleTranslogMetadataFilesAsync();
         }
     }
+
+    protected void onDelete() {
+        if (primaryModeSupplier.getAsBoolean() == false) {
+            logger.trace("skipped delete translog");
+            // NO-OP
+            return;
+        }
+        // clean up all remote translog files
+        translogTransferManager.delete();
+    }
 }

server/src/main/java/org/opensearch/index/translog/Translog.java

@@ -1807,6 +1807,8 @@ protected long getMinReferencedGen() throws IOException {
      */
     protected void setMinSeqNoToKeep(long seqNo) {}
 
+    protected void onDelete() {}
+
     /**
      * deletes all files associated with a reader. package-private to be able to simulate node failures at this point
      */

server/src/main/java/org/opensearch/index/translog/TranslogManager.java

@@ -126,4 +126,9 @@ public interface TranslogManager {
      * This might be required when segments are persisted via other mechanism than flush.
      */
     void setMinSeqNoToKeep(long seqNo);
+
+    /*
+    Clean up if any needed on deletion of index
+     */
+    void onDelete();
 }