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io.trino.operator.DeduplicatingDirectExchangeBuffer Maven / Gradle / Ivy
/*
* Licensed 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 under the License.
*/
package io.trino.operator;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ListMultimap;
import com.google.common.io.Closer;
import com.google.common.util.concurrent.FluentFuture;
import com.google.common.util.concurrent.FutureCallback;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.SettableFuture;
import com.google.errorprone.annotations.ThreadSafe;
import com.google.errorprone.annotations.concurrent.GuardedBy;
import io.airlift.log.Logger;
import io.airlift.slice.DynamicSliceOutput;
import io.airlift.slice.Slice;
import io.airlift.slice.SliceOutput;
import io.airlift.units.DataSize;
import io.airlift.units.Duration;
import io.opentelemetry.api.trace.Span;
import io.trino.annotation.NotThreadSafe;
import io.trino.exchange.ExchangeContextInstance;
import io.trino.exchange.ExchangeManagerRegistry;
import io.trino.execution.StageId;
import io.trino.execution.TaskId;
import io.trino.spi.QueryId;
import io.trino.spi.TrinoException;
import io.trino.spi.exchange.Exchange;
import io.trino.spi.exchange.ExchangeId;
import io.trino.spi.exchange.ExchangeManager;
import io.trino.spi.exchange.ExchangeSink;
import io.trino.spi.exchange.ExchangeSinkHandle;
import io.trino.spi.exchange.ExchangeSinkInstanceHandle;
import io.trino.spi.exchange.ExchangeSource;
import io.trino.spi.exchange.ExchangeSourceOutputSelector;
import java.io.Closeable;
import java.io.IOException;
import java.io.UncheckedIOException;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeoutException;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.base.Throwables.throwIfUnchecked;
import static com.google.common.base.Verify.verify;
import static com.google.common.collect.ImmutableMap.toImmutableMap;
import static com.google.common.collect.ImmutableSet.toImmutableSet;
import static com.google.common.collect.Multimaps.asMap;
import static com.google.common.util.concurrent.Futures.addCallback;
import static com.google.common.util.concurrent.Futures.immediateVoidFuture;
import static com.google.common.util.concurrent.Futures.nonCancellationPropagating;
import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
import static io.airlift.concurrent.MoreFutures.asVoid;
import static io.airlift.concurrent.MoreFutures.getFutureValue;
import static io.airlift.concurrent.MoreFutures.toListenableFuture;
import static io.trino.execution.scheduler.Exchanges.getAllSourceHandles;
import static io.trino.operator.RetryPolicy.QUERY;
import static io.trino.spi.StandardErrorCode.REMOTE_TASK_FAILED;
import static io.trino.spi.block.PageBuilderStatus.DEFAULT_MAX_PAGE_SIZE_IN_BYTES;
import static java.lang.Math.max;
import static java.util.Objects.requireNonNull;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static java.util.concurrent.TimeUnit.SECONDS;
public class DeduplicatingDirectExchangeBuffer
implements DirectExchangeBuffer
{
private static final Logger log = Logger.get(DeduplicatingDirectExchangeBuffer.class);
private static final Duration SINK_INSTANCE_HANDLE_GET_TIMEOUT = Duration.succinctDuration(60, SECONDS);
private final Executor executor;
@GuardedBy("this")
private final Set allTasks = new HashSet<>();
@GuardedBy("this")
private boolean noMoreTasks;
@GuardedBy("this")
private final Set successfulTasks = new HashSet<>();
@GuardedBy("this")
private final Map failedTasks = new HashMap<>();
@GuardedBy("this")
private int maxAttemptId;
@GuardedBy("this")
private final PageBuffer pageBuffer;
private final SettableFuture outputReady = SettableFuture.create();
@GuardedBy("this")
private OutputSource outputSource;
@GuardedBy("this")
private long maxRetainedSizeInBytes;
@GuardedBy("this")
private Throwable failure;
@GuardedBy("this")
private boolean closed;
public DeduplicatingDirectExchangeBuffer(
Executor executor,
DataSize bufferCapacity,
RetryPolicy retryPolicy,
ExchangeManagerRegistry exchangeManagerRegistry,
QueryId queryId,
Span parentSpan,
ExchangeId exchangeId)
{
this.executor = requireNonNull(executor, "executor is null");
checkArgument(retryPolicy == QUERY, "the class is used for query level retries only, got: %s", retryPolicy);
this.pageBuffer = new PageBuffer(
exchangeManagerRegistry,
queryId,
parentSpan,
exchangeId,
executor,
bufferCapacity);
}
@Override
public synchronized ListenableFuture isBlocked()
{
if (failure != null || closed) {
return immediateVoidFuture();
}
if (!outputReady.isDone()) {
return nonCancellationPropagating(Futures.transformAsync(outputReady, _ -> {
synchronized (this) {
if (outputSource != null) {
return outputSource.isBlocked();
}
return immediateVoidFuture();
}
}, directExecutor()));
}
checkState(outputSource != null, "outputSource is expected to be set");
return outputSource.isBlocked();
}
@Override
public synchronized Slice pollPage()
{
throwIfFailed();
if (closed) {
return null;
}
if (!outputReady.isDone()) {
return null;
}
checkState(outputSource != null, "outputSource is expected to be set");
Slice page = outputSource.getNext();
updateMaxRetainedSize();
return page;
}
@Override
public synchronized void addTask(TaskId taskId)
{
if (closed) {
return;
}
checkState(!noMoreTasks, "no more tasks expected");
checkState(allTasks.add(taskId), "task already registered: %s", taskId);
if (taskId.getAttemptId() > maxAttemptId) {
maxAttemptId = taskId.getAttemptId();
pageBuffer.removePagesForPreviousAttempts(maxAttemptId);
updateMaxRetainedSize();
}
}
@Override
public synchronized void addPages(TaskId taskId, List pages)
{
if (closed) {
return;
}
if (failure != null) {
return;
}
checkState(allTasks.contains(taskId), "task is not registered: %s", taskId);
checkState(!successfulTasks.contains(taskId), "task is finished: %s", taskId);
checkState(!failedTasks.containsKey(taskId), "task is failed: %s", taskId);
if (taskId.getAttemptId() < maxAttemptId) {
return;
}
try {
pageBuffer.addPages(taskId, pages);
updateMaxRetainedSize();
}
catch (RuntimeException e) {
fail(e);
}
}
@Override
public synchronized void taskFinished(TaskId taskId)
{
if (closed) {
return;
}
checkState(allTasks.contains(taskId), "task is not registered: %s", taskId);
checkState(!failedTasks.containsKey(taskId), "task is failed: %s", taskId);
checkState(successfulTasks.add(taskId), "task is finished: %s", taskId);
checkInputFinished();
}
@Override
public synchronized void taskFailed(TaskId taskId, Throwable t)
{
if (closed) {
return;
}
checkState(allTasks.contains(taskId), "task is not registered: %s", taskId);
checkState(!successfulTasks.contains(taskId), "task is finished: %s", taskId);
checkState(failedTasks.put(taskId, t) == null, "task is already failed: %s", taskId);
checkInputFinished();
}
@Override
public synchronized void noMoreTasks()
{
if (closed) {
return;
}
noMoreTasks = true;
checkInputFinished();
}
@GuardedBy("this")
private void checkInputFinished()
{
if (failure != null) {
return;
}
if (outputSource != null) {
return;
}
if (!noMoreTasks) {
return;
}
Set latestAttemptTasks = allTasks.stream()
.filter(taskId -> taskId.getAttemptId() == maxAttemptId)
.collect(toImmutableSet());
if (successfulTasks.containsAll(latestAttemptTasks)) {
outputSource = pageBuffer.createOutputSource(latestAttemptTasks);
unblock(outputReady);
return;
}
Map failures = failedTasks.entrySet().stream()
.filter(entry -> entry.getKey().getAttemptId() == maxAttemptId)
.collect(toImmutableMap(Map.Entry::getKey, Map.Entry::getValue));
Throwable failure = null;
for (Map.Entry entry : failures.entrySet()) {
TaskId taskId = entry.getKey();
Throwable taskFailure = entry.getValue();
if (taskFailure instanceof TrinoException && REMOTE_TASK_FAILED.toErrorCode().equals(((TrinoException) taskFailure).getErrorCode())) {
// This error indicates that a downstream task was trying to fetch results from an upstream task that is marked as failed
// Instead of failing a downstream task let the coordinator handle and report the failure of an upstream task to ensure correct error reporting
log.debug("Task failure discovered while fetching task results: %s", taskId);
continue;
}
if (failure == null) {
failure = taskFailure;
}
else if (failure != taskFailure) {
failure.addSuppressed(taskFailure);
}
}
if (failure != null) {
fail(failure);
}
}
@Override
public synchronized boolean isFinished()
{
return failure == null && (closed || (outputSource != null && outputSource.isFinished()));
}
@Override
public synchronized boolean isFailed()
{
return failure != null;
}
@Override
public synchronized long getRemainingCapacityInBytes()
{
// this buffer is always ready to accept more data
return Long.MAX_VALUE;
}
@Override
public synchronized long getRetainedSizeInBytes()
{
long retainedSizeInBytes = pageBuffer.getRetainedSizeInBytes();
if (outputSource != null) {
retainedSizeInBytes += outputSource.getRetainedSizeInBytes();
}
return retainedSizeInBytes;
}
@Override
public synchronized long getMaxRetainedSizeInBytes()
{
return maxRetainedSizeInBytes;
}
@Override
@GuardedBy("this")
public int getBufferedPageCount()
{
return pageBuffer.getBufferedPageCount();
}
@Override
@GuardedBy("this")
public long getSpilledBytes()
{
return pageBuffer.getSpilledBytes();
}
@Override
@GuardedBy("this")
public int getSpilledPageCount()
{
return pageBuffer.getSpilledPageCount();
}
@Override
public synchronized void close()
{
if (closed) {
return;
}
closed = true;
closeAndUnblock();
}
@GuardedBy("this")
private void fail(Throwable failure)
{
this.failure = failure;
closeAndUnblock();
}
@GuardedBy("this")
private void throwIfFailed()
{
if (failure != null) {
throwIfUnchecked(failure);
throw new RuntimeException(failure);
}
}
@GuardedBy("this")
private void closeAndUnblock()
{
try (Closer closer = Closer.create()) {
closer.register(pageBuffer);
closer.register(outputSource);
}
catch (IOException e) {
throw new UncheckedIOException(e);
}
finally {
unblock(outputReady);
}
}
@GuardedBy("this")
private void updateMaxRetainedSize()
{
maxRetainedSizeInBytes = max(maxRetainedSizeInBytes, getRetainedSizeInBytes());
}
private void unblock(SettableFuture blocked)
{
executor.execute(() -> blocked.set(null));
}
@ThreadSafe
private static class PageBuffer
implements Closeable
{
private final ExchangeManagerRegistry exchangeManagerRegistry;
private final QueryId queryId;
private final Span parentSpan;
private final ExchangeId exchangeId;
private final Executor executor;
private final long pageBufferCapacityInBytes;
@GuardedBy("this")
private final ListMultimap pageBuffer = ArrayListMultimap.create();
@GuardedBy("this")
private long pageBufferRetainedSizeInBytes;
@GuardedBy("this")
private ExchangeManager exchangeManager;
@GuardedBy("this")
private Exchange exchange;
@GuardedBy("this")
private ExchangeSinkHandle sinkHandle;
@GuardedBy("this")
private ExchangeSink exchangeSink;
@GuardedBy("this")
private SliceOutput writeBuffer;
@GuardedBy("this")
private int bufferedPageCount;
@GuardedBy("this")
private long spilledBytes;
@GuardedBy("this")
private int spilledPageCount;
@GuardedBy("this")
private boolean inputFinished;
@GuardedBy("this")
private boolean closed;
private PageBuffer(
ExchangeManagerRegistry exchangeManagerRegistry,
QueryId queryId,
Span parentSpan,
ExchangeId exchangeId,
Executor executor,
DataSize pageBufferCapacity)
{
this.exchangeManagerRegistry = requireNonNull(exchangeManagerRegistry, "exchangeManagerRegistry is null");
this.queryId = requireNonNull(queryId, "queryId is null");
this.parentSpan = requireNonNull(parentSpan, "querySpan is null");
this.exchangeId = requireNonNull(exchangeId, "exchangeId is null");
this.executor = requireNonNull(executor, "executor is null");
this.pageBufferCapacityInBytes = pageBufferCapacity.toBytes();
}
public synchronized void addPages(TaskId taskId, List pages)
{
if (closed) {
return;
}
if (inputFinished) {
// ignore extra pages after input is marked as finished
return;
}
long pagesRetainedSizeInBytes = getRetainedSizeInBytes(pages);
if (exchangeSink == null && pageBufferRetainedSizeInBytes + pagesRetainedSizeInBytes <= pageBufferCapacityInBytes) {
pageBuffer.putAll(taskId, pages);
pageBufferRetainedSizeInBytes += pagesRetainedSizeInBytes;
bufferedPageCount += pages.size();
return;
}
if (exchangeSink == null) {
verify(exchangeManager == null, "exchangeManager is not expected to be initialized");
verify(exchange == null, "exchange is not expected to be initialized");
verify(sinkHandle == null, "sinkHandle is not expected to be initialized");
verify(writeBuffer == null, "writeBuffer is not expected to be initialized");
exchangeManager = exchangeManagerRegistry.getExchangeManager();
exchange = exchangeManager.createExchange(new ExchangeContextInstance(queryId, exchangeId, parentSpan), 1, true);
sinkHandle = exchange.addSink(0);
exchange.noMoreSinks();
ExchangeSinkInstanceHandle sinkInstanceHandle;
try {
sinkInstanceHandle = exchange.instantiateSink(this.sinkHandle, 0).get(SINK_INSTANCE_HANDLE_GET_TIMEOUT.toMillis(), MILLISECONDS);
}
catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new RuntimeException(e);
}
catch (Exception e) {
throw new RuntimeException(e);
}
exchangeSink = exchangeManager.createSink(sinkInstanceHandle);
writeBuffer = new DynamicSliceOutput(DEFAULT_MAX_PAGE_SIZE_IN_BYTES);
}
if (!pageBuffer.isEmpty()) {
for (Map.Entry> entry : asMap(pageBuffer).entrySet()) {
writeToSink(entry.getKey(), entry.getValue());
}
pageBuffer.clear();
pageBufferRetainedSizeInBytes = 0;
}
writeToSink(taskId, pages);
bufferedPageCount += pages.size();
}
private static long getRetainedSizeInBytes(List pages)
{
long result = 0;
for (Slice page : pages) {
result += page.getRetainedSize();
}
return result;
}
@GuardedBy("this")
private void writeToSink(TaskId taskId, List pages)
{
verify(exchangeSink != null, "exchangeSink is expected to be initialized");
verify(writeBuffer != null, "writeBuffer is expected to be initialized");
for (Slice page : pages) {
// wait for the sink to unblock
while (true) {
try {
exchangeSink.isBlocked().get(1, SECONDS);
break;
}
catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new RuntimeException(e);
}
catch (ExecutionException e) {
throw new RuntimeException(e);
}
catch (TimeoutException e) {
updateSinkInstanceHandleIfNecessary();
}
}
writeBuffer.writeInt(taskId.getStageId().getId());
writeBuffer.writeInt(taskId.getPartitionId());
writeBuffer.writeInt(taskId.getAttemptId());
writeBuffer.writeBytes(page);
exchangeSink.add(0, writeBuffer.slice().copy());
writeBuffer.reset();
spilledBytes += page.length();
spilledPageCount++;
}
}
@GuardedBy("this")
private void updateSinkInstanceHandleIfNecessary()
{
verify(Thread.holdsLock(this), "this method is expected to be called under a lock");
verify(exchange != null, "exchange is null");
verify(exchangeSink != null, "exchangeSink is null");
verify(sinkHandle != null, "sinkHandle is null");
if (exchangeSink.isHandleUpdateRequired()) {
CompletableFuture sinkInstanceHandleFuture = exchange.updateSinkInstanceHandle(sinkHandle, 0);
ExchangeSinkInstanceHandle sinkInstanceHandle;
try {
sinkInstanceHandle = sinkInstanceHandleFuture.get(SINK_INSTANCE_HANDLE_GET_TIMEOUT.toMillis(), MILLISECONDS);
}
catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new RuntimeException(e);
}
catch (Exception e) {
throw new RuntimeException(e);
}
exchangeSink.updateHandle(sinkInstanceHandle);
}
}
public synchronized void removePagesForPreviousAttempts(int currentAttemptId)
{
checkState(!inputFinished, "input is finished");
if (closed) {
return;
}
long removedPagesRetainedSizeInBytes = 0;
int removedPagesCount = 0;
Iterator>> iterator = asMap(pageBuffer).entrySet().iterator();
while (iterator.hasNext()) {
Map.Entry> entry = iterator.next();
TaskId taskId = entry.getKey();
if (taskId.getAttemptId() < currentAttemptId) {
for (Slice page : entry.getValue()) {
removedPagesRetainedSizeInBytes += page.getRetainedSize();
removedPagesCount++;
}
iterator.remove();
}
}
pageBufferRetainedSizeInBytes -= removedPagesRetainedSizeInBytes;
bufferedPageCount -= removedPagesCount;
}
public synchronized OutputSource createOutputSource(Set selectedTasks)
{
checkState(!inputFinished, "input is already marked as finished and page source has already been created");
inputFinished = true;
if (exchangeSink == null) {
Iterator iterator = pageBuffer.entries().stream()
.filter(entry -> selectedTasks.contains(entry.getKey()))
.map(Map.Entry::getValue)
.iterator();
return new InMemoryBufferOutputSource(iterator);
}
verify(exchangeManager != null, "exchangeManager is expected to be initialized");
verify(exchange != null, "exchange is expected to be initialized");
verify(sinkHandle != null, "sinkHandle is expected to be initialized");
// no more data will be added, the buffer can be safely discarded
writeBuffer = null;
// Finish ExchangeSink and create ExchangeSource asynchronously to avoid blocking an ExchangeClient thread for potentially substantial amount of time
ListenableFuture exchangeSourceFuture = FluentFuture.from(toListenableFuture(exchangeSink.finish()))
.transformAsync(_ -> {
exchange.sinkFinished(sinkHandle, 0);
exchange.allRequiredSinksFinished();
synchronized (this) {
exchangeSink = null;
sinkHandle = null;
}
return getAllSourceHandles(exchange.getSourceHandles());
}, executor)
.transform(handles -> {
ExchangeSource source = exchangeManager.createSource();
try {
source.setOutputSelector(ExchangeSourceOutputSelector.builder(ImmutableSet.of(exchangeId))
.include(exchangeId, 0, 0)
.setPartitionCount(exchangeId, 1)
.setFinal()
.build());
source.addSourceHandles(handles);
source.noMoreSourceHandles();
return source;
}
catch (Throwable t) {
try {
source.close();
}
catch (Throwable closeFailure) {
if (closeFailure != t) {
t.addSuppressed(closeFailure);
}
}
throw t;
}
}, executor);
return new ExchangeOutputSource(selectedTasks, queryId, exchangeSourceFuture);
}
public synchronized long getRetainedSizeInBytes()
{
long result = pageBufferRetainedSizeInBytes;
if (exchangeSink != null) {
result += exchangeSink.getMemoryUsage();
}
if (writeBuffer != null) {
result += writeBuffer.getRetainedSize();
}
return result;
}
public synchronized int getBufferedPageCount()
{
return bufferedPageCount;
}
public synchronized long getSpilledBytes()
{
return spilledBytes;
}
public synchronized int getSpilledPageCount()
{
return spilledPageCount;
}
@Override
public synchronized void close()
{
if (closed) {
return;
}
closed = true;
pageBuffer.clear();
pageBufferRetainedSizeInBytes = 0;
bufferedPageCount = 0;
writeBuffer = null;
if (exchangeSink != null) {
try {
exchangeSink.abort().whenComplete((result, failure) -> {
if (failure != null) {
log.warn(failure, "Error aborting exchange sink");
}
});
}
catch (RuntimeException e) {
log.warn(e, "Error aborting exchange sink");
}
exchangeSink = null;
}
if (exchange != null) {
exchange.close();
}
}
}
@NotThreadSafe
private interface OutputSource
extends Closeable
{
Slice getNext();
boolean isFinished();
ListenableFuture isBlocked();
long getRetainedSizeInBytes();
}
@NotThreadSafe
private static class InMemoryBufferOutputSource
implements OutputSource
{
private final Iterator iterator;
private InMemoryBufferOutputSource(Iterator iterator)
{
this.iterator = requireNonNull(iterator, "iterator is null");
}
@Override
public Slice getNext()
{
if (!iterator.hasNext()) {
return null;
}
return iterator.next();
}
@Override
public boolean isFinished()
{
return !iterator.hasNext();
}
@Override
public ListenableFuture isBlocked()
{
return immediateVoidFuture();
}
@Override
public long getRetainedSizeInBytes()
{
return 0;
}
@Override
public void close()
{
}
}
@NotThreadSafe
private static class ExchangeOutputSource
implements OutputSource
{
private final Set selectedTasks;
private final QueryId queryId;
private ListenableFuture exchangeSourceFuture;
private ExchangeSource exchangeSource;
private boolean finished;
private ExchangeOutputSource(
Set selectedTasks,
QueryId queryId,
ListenableFuture exchangeSourceFuture)
{
this.selectedTasks = ImmutableSet.copyOf(requireNonNull(selectedTasks, "selectedTasks is null"));
this.queryId = requireNonNull(queryId, "queryId is null");
this.exchangeSourceFuture = requireNonNull(exchangeSourceFuture, "exchangeSourceFuture is null");
}
@Override
public Slice getNext()
{
if (finished) {
return null;
}
if (exchangeSource == null) {
if (!exchangeSourceFuture.isDone()) {
return null;
}
exchangeSource = getFutureValue(exchangeSourceFuture);
}
while (!exchangeSource.isFinished()) {
if (!exchangeSource.isBlocked().isDone()) {
return null;
}
Slice buffer = exchangeSource.read();
if (buffer == null) {
continue;
}
int stageId = buffer.getInt(0);
int partitionId = buffer.getInt(Integer.BYTES);
int attemptId = buffer.getInt(Integer.BYTES * 2);
TaskId taskId = new TaskId(new StageId(queryId, stageId), partitionId, attemptId);
if (!selectedTasks.contains(taskId)) {
continue;
}
return buffer.slice(Integer.BYTES * 3, buffer.length() - Integer.BYTES * 3);
}
close();
return null;
}
@Override
public boolean isFinished()
{
return finished;
}
@Override
public ListenableFuture isBlocked()
{
if (finished) {
return immediateVoidFuture();
}
if (!exchangeSourceFuture.isDone()) {
return nonCancellationPropagating(asVoid(Futures.transformAsync(
exchangeSourceFuture,
exchangeSource -> toListenableFuture(exchangeSource.isBlocked()),
directExecutor())));
}
if (exchangeSource != null) {
CompletableFuture blocked = exchangeSource.isBlocked();
if (!blocked.isDone()) {
return nonCancellationPropagating(toListenableFuture(blocked));
}
}
return immediateVoidFuture();
}
@Override
public long getRetainedSizeInBytes()
{
if (exchangeSource != null) {
return exchangeSource.getMemoryUsage();
}
return 0;
}
@Override
public void close()
{
if (finished) {
return;
}
finished = true;
exchangeSource = null;
addCallback(exchangeSourceFuture, new FutureCallback<>()
{
@Override
public void onSuccess(ExchangeSource exchangeSource)
{
try {
exchangeSource.close();
}
catch (RuntimeException e) {
log.warn(e, "error closing exchange source");
}
}
@Override
public void onFailure(Throwable ignored)
{
// The callback is needed to safely close the exchange source
// It a failure occurred it is expected to be propagated by the getNext method
}
}, directExecutor());
exchangeSourceFuture = null;
}
}
}
