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* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you under
* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
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package org.elasticsearch.indices.recovery;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.message.ParameterizedMessage;
import org.apache.logging.log4j.util.Supplier;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.index.IndexFormatTooNewException;
import org.apache.lucene.index.IndexFormatTooOldException;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.BytesRefIterator;
import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.ExceptionsHelper;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.UUIDs;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.logging.Loggers;
import org.elasticsearch.common.lucene.Lucene;
import org.elasticsearch.common.util.Callback;
import org.elasticsearch.common.util.CancellableThreads;
import org.elasticsearch.common.util.concurrent.AbstractRefCounted;
import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
import org.elasticsearch.index.shard.IndexShard;
import org.elasticsearch.index.shard.ShardId;
import org.elasticsearch.index.shard.TranslogRecoveryPerformer;
import org.elasticsearch.index.store.Store;
import org.elasticsearch.index.store.StoreFileMetaData;
import org.elasticsearch.index.translog.Translog;
import java.io.IOException;
import java.nio.file.Path;
import java.util.Arrays;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;
/**
* Represents a recovery where the current node is the target node of the recovery. To track recoveries in a central place, instances of
* this class are created through {@link RecoveriesCollection}.
*/
public class RecoveryTarget extends AbstractRefCounted implements RecoveryTargetHandler {
private final Logger logger;
private static final AtomicLong idGenerator = new AtomicLong();
private static final String RECOVERY_PREFIX = "recovery.";
private final ShardId shardId;
private final long recoveryId;
private final IndexShard indexShard;
private final DiscoveryNode sourceNode;
private final String tempFilePrefix;
private final Store store;
private final PeerRecoveryTargetService.RecoveryListener listener;
private final Callback<Long> ensureClusterStateVersionCallback;
private final AtomicBoolean finished = new AtomicBoolean();
private final ConcurrentMap<String, IndexOutput> openIndexOutputs = ConcurrentCollections.newConcurrentMap();
private final CancellableThreads cancellableThreads;
// last time this status was accessed
private volatile long lastAccessTime = System.nanoTime();
// latch that can be used to blockingly wait for RecoveryTarget to be closed
private final CountDownLatch closedLatch = new CountDownLatch(1);
private final Map<String, String> tempFileNames = ConcurrentCollections.newConcurrentMap();
/**
* Creates a new recovery target object that represents a recovery to the provided shard.
*
* @param indexShard local shard where we want to recover to
* @param sourceNode source node of the recovery where we recover from
* @param listener called when recovery is completed/failed
* @param ensureClusterStateVersionCallback callback to ensure that the current node is at least on a cluster state with the provided
* version; necessary for primary relocation so that new primary knows about all other ongoing
* replica recoveries when replicating documents (see {@link RecoverySourceHandler})
*/
public RecoveryTarget(final IndexShard indexShard,
final DiscoveryNode sourceNode,
final PeerRecoveryTargetService.RecoveryListener listener,
final Callback<Long> ensureClusterStateVersionCallback) {
super("recovery_status");
this.cancellableThreads = new CancellableThreads();
this.recoveryId = idGenerator.incrementAndGet();
this.listener = listener;
this.logger = Loggers.getLogger(getClass(), indexShard.indexSettings().getSettings(), indexShard.shardId());
this.indexShard = indexShard;
this.sourceNode = sourceNode;
this.shardId = indexShard.shardId();
this.tempFilePrefix = RECOVERY_PREFIX + UUIDs.base64UUID() + ".";
this.store = indexShard.store();
this.ensureClusterStateVersionCallback = ensureClusterStateVersionCallback;
// make sure the store is not released until we are done.
store.incRef();
indexShard.recoveryStats().incCurrentAsTarget();
}
/**
* Returns a fresh recovery target to retry recovery from the same source node onto the same shard and using the same listener.
*
* @return a copy of this recovery target
*/
public RecoveryTarget retryCopy() {
return new RecoveryTarget(indexShard, sourceNode, listener, ensureClusterStateVersionCallback);
}
public long recoveryId() {
return recoveryId;
}
public ShardId shardId() {
return shardId;
}
public IndexShard indexShard() {
ensureRefCount();
return indexShard;
}
public DiscoveryNode sourceNode() {
return this.sourceNode;
}
public RecoveryState state() {
return indexShard.recoveryState();
}
public CancellableThreads cancellableThreads() {
return cancellableThreads;
}
/** return the last time this RecoveryStatus was used (based on System.nanoTime() */
public long lastAccessTime() {
return lastAccessTime;
}
/** sets the lasAccessTime flag to now */
public void setLastAccessTime() {
lastAccessTime = System.nanoTime();
}
public Store store() {
ensureRefCount();
return store;
}
public RecoveryState.Stage stage() {
return state().getStage();
}
/** renames all temporary files to their true name, potentially overriding existing files */
public void renameAllTempFiles() throws IOException {
ensureRefCount();
store.renameTempFilesSafe(tempFileNames);
}
/**
* Closes the current recovery target and waits up to a certain timeout for resources to be freed.
* Returns true if resetting the recovery was successful, false if the recovery target is already cancelled / failed or marked as done.
*/
boolean resetRecovery(CancellableThreads newTargetCancellableThreads) throws IOException {
if (finished.compareAndSet(false, true)) {
try {
logger.debug("reset of recovery with shard {} and id [{}]", shardId, recoveryId);
} finally {
// release the initial reference. recovery files will be cleaned as soon as ref count goes to zero, potentially now.
decRef();
}
try {
newTargetCancellableThreads.execute(closedLatch::await);
} catch (CancellableThreads.ExecutionCancelledException e) {
logger.trace("new recovery target cancelled for shard {} while waiting on old recovery target with id [{}] to close",
shardId, recoveryId);
return false;
}
RecoveryState.Stage stage = indexShard.recoveryState().getStage();
if (indexShard.recoveryState().getPrimary() && (stage == RecoveryState.Stage.FINALIZE || stage == RecoveryState.Stage.DONE)) {
// once primary relocation has moved past the finalization step, the relocation source can be moved to RELOCATED state
// and start indexing as primary into the target shard (see TransportReplicationAction). Resetting the target shard in this
// state could mean that indexing is halted until the recovery retry attempt is completed and could also destroy existing
// documents indexed and acknowledged before the reset.
assert stage != RecoveryState.Stage.DONE : "recovery should not have completed when it's being reset";
throw new IllegalStateException("cannot reset recovery as previous attempt made it past finalization step");
}
indexShard.performRecoveryRestart();
return true;
}
return false;
}
/**
* cancel the recovery. calling this method will clean temporary files and release the store
* unless this object is in use (in which case it will be cleaned once all ongoing users call
* {@link #decRef()}
* <p>
* if {@link #cancellableThreads()} was used, the threads will be interrupted.
*/
public void cancel(String reason) {
if (finished.compareAndSet(false, true)) {
try {
logger.debug("recovery canceled (reason: [{}])", reason);
cancellableThreads.cancel(reason);
} finally {
// release the initial reference. recovery files will be cleaned as soon as ref count goes to zero, potentially now
decRef();
}
}
}
/**
* fail the recovery and call listener
*
* @param e exception that encapsulating the failure
* @param sendShardFailure indicates whether to notify the master of the shard failure
*/
public void fail(RecoveryFailedException e, boolean sendShardFailure) {
if (finished.compareAndSet(false, true)) {
try {
notifyListener(e, sendShardFailure);
} finally {
try {
cancellableThreads.cancel("failed recovery [" + ExceptionsHelper.stackTrace(e) + "]");
} finally {
// release the initial reference. recovery files will be cleaned as soon as ref count goes to zero, potentially now
decRef();
}
}
}
}
public void notifyListener(RecoveryFailedException e, boolean sendShardFailure) {
listener.onRecoveryFailure(state(), e, sendShardFailure);
}
/** mark the current recovery as done */
public void markAsDone() {
if (finished.compareAndSet(false, true)) {
assert tempFileNames.isEmpty() : "not all temporary files are renamed";
try {
// this might still throw an exception ie. if the shard is CLOSED due to some other event.
// it's safer to decrement the reference in a try finally here.
indexShard.postRecovery("peer recovery done");
} finally {
// release the initial reference. recovery files will be cleaned as soon as ref count goes to zero, potentially now
decRef();
}
listener.onRecoveryDone(state());
}
}
/** Get a temporary name for the provided file name. */
public String getTempNameForFile(String origFile) {
return tempFilePrefix + origFile;
}
public IndexOutput getOpenIndexOutput(String key) {
ensureRefCount();
return openIndexOutputs.get(key);
}
/** remove and {@link org.apache.lucene.store.IndexOutput} for a given file. It is the caller's responsibility to close it */
public IndexOutput removeOpenIndexOutputs(String name) {
ensureRefCount();
return openIndexOutputs.remove(name);
}
/**
* Creates an {@link org.apache.lucene.store.IndexOutput} for the given file name. Note that the
* IndexOutput actually point at a temporary file.
* <p>
* Note: You can use {@link #getOpenIndexOutput(String)} with the same filename to retrieve the same IndexOutput
* at a later stage
*/
public IndexOutput openAndPutIndexOutput(String fileName, StoreFileMetaData metaData, Store store) throws IOException {
ensureRefCount();
String tempFileName = getTempNameForFile(fileName);
if (tempFileNames.containsKey(tempFileName)) {
throw new IllegalStateException("output for file [" + fileName + "] has already been created");
}
// add first, before it's created
tempFileNames.put(tempFileName, fileName);
IndexOutput indexOutput = store.createVerifyingOutput(tempFileName, metaData, IOContext.DEFAULT);
openIndexOutputs.put(fileName, indexOutput);
return indexOutput;
}
@Override
protected void closeInternal() {
try {
// clean open index outputs
Iterator<Entry<String, IndexOutput>> iterator = openIndexOutputs.entrySet().iterator();
while (iterator.hasNext()) {
Map.Entry<String, IndexOutput> entry = iterator.next();
logger.trace("closing IndexOutput file [{}]", entry.getValue());
try {
entry.getValue().close();
} catch (Exception e) {
logger.debug(
(Supplier<?>) () -> new ParameterizedMessage("error while closing recovery output [{}]", entry.getValue()), e);
}
iterator.remove();
}
// trash temporary files
for (String file : tempFileNames.keySet()) {
logger.trace("cleaning temporary file [{}]", file);
store.deleteQuiet(file);
}
} finally {
// free store. increment happens in constructor
store.decRef();
indexShard.recoveryStats().decCurrentAsTarget();
closedLatch.countDown();
}
}
@Override
public String toString() {
return shardId + " [" + recoveryId + "]";
}
private void ensureRefCount() {
if (refCount() <= 0) {
throw new ElasticsearchException("RecoveryStatus is used but it's refcount is 0. Probably a mismatch between incRef/decRef " +
"calls");
}
}
/*** Implementation of {@link RecoveryTargetHandler } */
@Override
public void prepareForTranslogOperations(int totalTranslogOps) throws IOException {
state().getTranslog().totalOperations(totalTranslogOps);
indexShard().skipTranslogRecovery();
}
@Override
public void finalizeRecovery(final long globalCheckpoint) {
indexShard().updateGlobalCheckpointOnReplica(globalCheckpoint);
final IndexShard indexShard = indexShard();
indexShard.finalizeRecovery();
}
@Override
public void ensureClusterStateVersion(long clusterStateVersion) {
ensureClusterStateVersionCallback.handle(clusterStateVersion);
}
@Override
public long indexTranslogOperations(
List<Translog.Operation> operations, int totalTranslogOps) throws TranslogRecoveryPerformer.BatchOperationException {
final RecoveryState.Translog translog = state().getTranslog();
translog.totalOperations(totalTranslogOps);
assert indexShard().recoveryState() == state();
indexShard().performBatchRecovery(operations);
return indexShard().getLocalCheckpoint();
}
@Override
public void receiveFileInfo(List<String> phase1FileNames,
List<Long> phase1FileSizes,
List<String> phase1ExistingFileNames,
List<Long> phase1ExistingFileSizes,
int totalTranslogOps) {
final RecoveryState.Index index = state().getIndex();
for (int i = 0; i < phase1ExistingFileNames.size(); i++) {
index.addFileDetail(phase1ExistingFileNames.get(i), phase1ExistingFileSizes.get(i), true);
}
for (int i = 0; i < phase1FileNames.size(); i++) {
index.addFileDetail(phase1FileNames.get(i), phase1FileSizes.get(i), false);
}
state().getTranslog().totalOperations(totalTranslogOps);
state().getTranslog().totalOperationsOnStart(totalTranslogOps);
}
@Override
public void cleanFiles(int totalTranslogOps, Store.MetadataSnapshot sourceMetaData) throws IOException {
state().getTranslog().totalOperations(totalTranslogOps);
// first, we go and move files that were created with the recovery id suffix to
// the actual names, its ok if we have a corrupted index here, since we have replicas
// to recover from in case of a full cluster shutdown just when this code executes...
renameAllTempFiles();
final Store store = store();
try {
store.cleanupAndVerify("recovery CleanFilesRequestHandler", sourceMetaData);
} catch (CorruptIndexException | IndexFormatTooNewException | IndexFormatTooOldException ex) {
// this is a fatal exception at this stage.
// this means we transferred files from the remote that have not be checksummed and they are
// broken. We have to clean up this shard entirely, remove all files and bubble it up to the
// source shard since this index might be broken there as well? The Source can handle this and checks
// its content on disk if possible.
try {
try {
store.removeCorruptionMarker();
} finally {
Lucene.cleanLuceneIndex(store.directory()); // clean up and delete all files
}
} catch (Exception e) {
logger.debug("Failed to clean lucene index", e);
ex.addSuppressed(e);
}
RecoveryFailedException rfe = new RecoveryFailedException(state(), "failed to clean after recovery", ex);
fail(rfe, true);
throw rfe;
} catch (Exception ex) {
RecoveryFailedException rfe = new RecoveryFailedException(state(), "failed to clean after recovery", ex);
fail(rfe, true);
throw rfe;
}
}
@Override
public void writeFileChunk(StoreFileMetaData fileMetaData, long position, BytesReference content,
boolean lastChunk, int totalTranslogOps) throws IOException {
final Store store = store();
final String name = fileMetaData.name();
state().getTranslog().totalOperations(totalTranslogOps);
final RecoveryState.Index indexState = state().getIndex();
IndexOutput indexOutput;
if (position == 0) {
indexOutput = openAndPutIndexOutput(name, fileMetaData, store);
} else {
indexOutput = getOpenIndexOutput(name);
}
BytesRefIterator iterator = content.iterator();
BytesRef scratch;
while((scratch = iterator.next()) != null) { // we iterate over all pages - this is a 0-copy for all core impls
indexOutput.writeBytes(scratch.bytes, scratch.offset, scratch.length);
}
indexState.addRecoveredBytesToFile(name, content.length());
if (indexOutput.getFilePointer() >= fileMetaData.length() || lastChunk) {
try {
Store.verify(indexOutput);
} finally {
// we are done
indexOutput.close();
}
final String temporaryFileName = getTempNameForFile(name);
assert Arrays.asList(store.directory().listAll()).contains(temporaryFileName) :
"expected: [" + temporaryFileName + "] in " + Arrays.toString(store.directory().listAll());
store.directory().sync(Collections.singleton(temporaryFileName));
IndexOutput remove = removeOpenIndexOutputs(name);
assert remove == null || remove == indexOutput; // remove maybe null if we got finished
}
}
Path translogLocation() {
return indexShard().shardPath().resolveTranslog();
}
}