/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 under the License.
*/
package org.apache.hadoop.fs.s3a;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import com.amazonaws.AmazonClientException;
import com.amazonaws.event.ProgressEvent;
import com.amazonaws.event.ProgressEventType;
import com.amazonaws.event.ProgressListener;
import com.amazonaws.services.s3.model.CompleteMultipartUploadResult;
import com.amazonaws.services.s3.model.PartETag;
import com.amazonaws.services.s3.model.PutObjectRequest;
import com.amazonaws.services.s3.model.PutObjectResult;
import com.amazonaws.services.s3.model.UploadPartRequest;
import com.google.common.base.Preconditions;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.MoreExecutors;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.io.retry.RetryPolicies;
import org.apache.hadoop.io.retry.RetryPolicy;
import org.apache.hadoop.util.Progressable;
import static org.apache.hadoop.fs.s3a.S3AUtils.*;
import static org.apache.hadoop.fs.s3a.Statistic.*;
/**
* Upload files/parts directly via different buffering mechanisms:
* including memory and disk.
*
* If the stream is closed and no update has started, then the upload
* is instead done as a single PUT operation.
*
* Unstable: statistics and error handling might evolve.
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
class S3ABlockOutputStream extends OutputStream {
private static final Logger LOG =
LoggerFactory.getLogger(S3ABlockOutputStream.class);
/** Owner FileSystem. */
private final S3AFileSystem fs;
/** Object being uploaded. */
private final String key;
/** Size of all blocks. */
private final int blockSize;
/** Callback for progress. */
private final ProgressListener progressListener;
private final ListeningExecutorService executorService;
/**
* Retry policy for multipart commits; not all AWS SDK versions retry that.
*/
private final RetryPolicy retryPolicy =
RetryPolicies.retryUpToMaximumCountWithProportionalSleep(
5,
2000,
TimeUnit.MILLISECONDS);
/**
* Factory for blocks.
*/
private final S3ADataBlocks.BlockFactory blockFactory;
/** Preallocated byte buffer for writing single characters. */
private final byte[] singleCharWrite = new byte[1];
/** Multipart upload details; null means none started. */
private MultiPartUpload multiPartUpload;
/** Closed flag. */
private final AtomicBoolean closed = new AtomicBoolean(false);
/** Current data block. Null means none currently active */
private S3ADataBlocks.DataBlock activeBlock;
/** Count of blocks uploaded. */
private long blockCount = 0;
/** Statistics to build up. */
private final S3AInstrumentation.OutputStreamStatistics statistics;
/**
* Write operation helper; encapsulation of the filesystem operations.
*/
private final S3AFileSystem.WriteOperationHelper writeOperationHelper;
/**
* An S3A output stream which uploads partitions in a separate pool of
* threads; different {@link S3ADataBlocks.BlockFactory}
* instances can control where data is buffered.
*
* @param fs S3AFilesystem
* @param key S3 object to work on.
* @param executorService the executor service to use to schedule work
* @param progress report progress in order to prevent timeouts. If
* this object implements {@code ProgressListener} then it will be
* directly wired up to the AWS client, so receive detailed progress
* information.
* @param blockSize size of a single block.
* @param blockFactory factory for creating stream destinations
* @param statistics stats for this stream
* @param writeOperationHelper state of the write operation.
* @throws IOException on any problem
*/
S3ABlockOutputStream(S3AFileSystem fs,
String key,
ExecutorService executorService,
Progressable progress,
long blockSize,
S3ADataBlocks.BlockFactory blockFactory,
S3AInstrumentation.OutputStreamStatistics statistics,
S3AFileSystem.WriteOperationHelper writeOperationHelper)
throws IOException {
this.fs = fs;
this.key = key;
this.blockFactory = blockFactory;
this.blockSize = (int) blockSize;
this.statistics = statistics;
this.writeOperationHelper = writeOperationHelper;
Preconditions.checkArgument(blockSize >= Constants.MULTIPART_MIN_SIZE,
"Block size is too small: %d", blockSize);
this.executorService = MoreExecutors.listeningDecorator(executorService);
this.multiPartUpload = null;
this.progressListener = (progress instanceof ProgressListener) ?
(ProgressListener) progress
: new ProgressableListener(progress);
// create that first block. This guarantees that an open + close sequence
// writes a 0-byte entry.
createBlockIfNeeded();
LOG.debug("Initialized S3ABlockOutputStream for {}" +
" output to {}", writeOperationHelper, activeBlock);
}
/**
* Demand create a destination block.
* @return the active block; null if there isn't one.
* @throws IOException on any failure to create
*/
private synchronized S3ADataBlocks.DataBlock createBlockIfNeeded()
throws IOException {
if (activeBlock == null) {
blockCount++;
if (blockCount>= Constants.MAX_MULTIPART_COUNT) {
LOG.error("Number of partitions in stream exceeds limit for S3: "
+ Constants.MAX_MULTIPART_COUNT + " write may fail.");
}
activeBlock = blockFactory.create(blockCount, this.blockSize, statistics);
}
return activeBlock;
}
/**
* Synchronized accessor to the active block.
* @return the active block; null if there isn't one.
*/
private synchronized S3ADataBlocks.DataBlock getActiveBlock() {
return activeBlock;
}
/**
* Predicate to query whether or not there is an active block.
* @return true if there is an active block.
*/
private synchronized boolean hasActiveBlock() {
return activeBlock != null;
}
/**
* Clear the active block.
*/
private void clearActiveBlock() {
if (activeBlock != null) {
LOG.debug("Clearing active block");
}
synchronized (this) {
activeBlock = null;
}
}
/**
* Check for the filesystem being open.
* @throws IOException if the filesystem is closed.
*/
void checkOpen() throws IOException {
if (closed.get()) {
throw new IOException("Filesystem " + writeOperationHelper + " closed");
}
}
/**
* The flush operation does not trigger an upload; that awaits
* the next block being full. What it does do is call {@code flush() }
* on the current block, leaving it to choose how to react.
* @throws IOException Any IO problem.
*/
@Override
public synchronized void flush() throws IOException {
checkOpen();
S3ADataBlocks.DataBlock dataBlock = getActiveBlock();
if (dataBlock != null) {
dataBlock.flush();
}
}
/**
* Writes a byte to the destination. If this causes the buffer to reach
* its limit, the actual upload is submitted to the threadpool.
* @param b the int of which the lowest byte is written
* @throws IOException on any problem
*/
@Override
public synchronized void write(int b) throws IOException {
singleCharWrite[0] = (byte)b;
write(singleCharWrite, 0, 1);
}
/**
* Writes a range of bytes from to the memory buffer. If this causes the
* buffer to reach its limit, the actual upload is submitted to the
* threadpool and the remainder of the array is written to memory
* (recursively).
* @param source byte array containing
* @param offset offset in array where to start
* @param len number of bytes to be written
* @throws IOException on any problem
*/
@Override
public synchronized void write(byte[] source, int offset, int len)
throws IOException {
S3ADataBlocks.validateWriteArgs(source, offset, len);
checkOpen();
if (len == 0) {
return;
}
S3ADataBlocks.DataBlock block = createBlockIfNeeded();
int written = block.write(source, offset, len);
int remainingCapacity = block.remainingCapacity();
if (written < len) {
// not everything was written —the block has run out
// of capacity
// Trigger an upload then process the remainder.
LOG.debug("writing more data than block has capacity -triggering upload");
uploadCurrentBlock();
// tail recursion is mildly expensive, but given buffer sizes must be MB.
// it's unlikely to recurse very deeply.
this.write(source, offset + written, len - written);
} else {
if (remainingCapacity == 0) {
// the whole buffer is done, trigger an upload
uploadCurrentBlock();
}
}
}
/**
* Start an asynchronous upload of the current block.
* @throws IOException Problems opening the destination for upload
* or initializing the upload.
*/
private synchronized void uploadCurrentBlock() throws IOException {
Preconditions.checkState(hasActiveBlock(), "No active block");
LOG.debug("Writing block # {}", blockCount);
if (multiPartUpload == null) {
LOG.debug("Initiating Multipart upload");
multiPartUpload = new MultiPartUpload();
}
try {
multiPartUpload.uploadBlockAsync(getActiveBlock());
} finally {
// set the block to null, so the next write will create a new block.
clearActiveBlock();
}
}
/**
* Close the stream.
*
* This will not return until the upload is complete
* or the attempt to perform the upload has failed.
* Exceptions raised in this method are indicative that the write has
* failed and data is at risk of being lost.
* @throws IOException on any failure.
*/
@Override
public void close() throws IOException {
if (closed.getAndSet(true)) {
// already closed
LOG.debug("Ignoring close() as stream is already closed");
return;
}
S3ADataBlocks.DataBlock block = getActiveBlock();
boolean hasBlock = hasActiveBlock();
LOG.debug("{}: Closing block #{}: current block= {}",
this,
blockCount,
hasBlock ? block : "(none)");
try {
if (multiPartUpload == null) {
if (hasBlock) {
// no uploads of data have taken place, put the single block up.
// This must happen even if there is no data, so that 0 byte files
// are created.
putObject();
}
} else {
// there has already been at least one block scheduled for upload;
// put up the current then wait
if (hasBlock && block.hasData()) {
//send last part
uploadCurrentBlock();
}
// wait for the partial uploads to finish
final List<PartETag> partETags =
multiPartUpload.waitForAllPartUploads();
// then complete the operation
multiPartUpload.complete(partETags);
}
LOG.debug("Upload complete for {}", writeOperationHelper);
} catch (IOException ioe) {
writeOperationHelper.writeFailed(ioe);
throw ioe;
} finally {
closeAll(LOG, block, blockFactory);
LOG.debug("Statistics: {}", statistics);
closeAll(LOG, statistics);
clearActiveBlock();
}
// All end of write operations, including deleting fake parent directories
writeOperationHelper.writeSuccessful();
}
/**
* Upload the current block as a single PUT request; if the buffer
* is empty a 0-byte PUT will be invoked, as it is needed to create an
* entry at the far end.
* @throws IOException any problem.
*/
private void putObject() throws IOException {
LOG.debug("Executing regular upload for {}", writeOperationHelper);
final S3ADataBlocks.DataBlock block = getActiveBlock();
int size = block.dataSize();
final S3ADataBlocks.BlockUploadData uploadData = block.startUpload();
final PutObjectRequest putObjectRequest = uploadData.hasFile() ?
writeOperationHelper.newPutRequest(uploadData.getFile())
: writeOperationHelper.newPutRequest(uploadData.getUploadStream(), size);
long transferQueueTime = now();
BlockUploadProgress callback =
new BlockUploadProgress(
block, progressListener, transferQueueTime);
putObjectRequest.setGeneralProgressListener(callback);
statistics.blockUploadQueued(size);
ListenableFuture<PutObjectResult> putObjectResult =
executorService.submit(new Callable<PutObjectResult>() {
@Override
public PutObjectResult call() throws Exception {
PutObjectResult result;
try {
// the putObject call automatically closes the input
// stream afterwards.
result = writeOperationHelper.putObject(putObjectRequest);
} finally {
closeAll(LOG, uploadData, block);
}
return result;
}
});
clearActiveBlock();
//wait for completion
try {
putObjectResult.get();
} catch (InterruptedException ie) {
LOG.warn("Interrupted object upload", ie);
Thread.currentThread().interrupt();
} catch (ExecutionException ee) {
throw extractException("regular upload", key, ee);
}
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder(
"S3ABlockOutputStream{");
sb.append(writeOperationHelper.toString());
sb.append(", blockSize=").append(blockSize);
// unsynced access; risks consistency in exchange for no risk of deadlock.
S3ADataBlocks.DataBlock block = activeBlock;
if (block != null) {
sb.append(", activeBlock=").append(block);
}
sb.append('}');
return sb.toString();
}
private void incrementWriteOperations() {
fs.incrementWriteOperations();
}
/**
* Current time in milliseconds.
* @return time
*/
private long now() {
return System.currentTimeMillis();
}
/**
* Get the statistics for this stream.
* @return stream statistics
*/
S3AInstrumentation.OutputStreamStatistics getStatistics() {
return statistics;
}
/**
* Multiple partition upload.
*/
private class MultiPartUpload {
private final String uploadId;
private final List<ListenableFuture<PartETag>> partETagsFutures;
MultiPartUpload() throws IOException {
this.uploadId = writeOperationHelper.initiateMultiPartUpload();
this.partETagsFutures = new ArrayList<>(2);
LOG.debug("Initiated multi-part upload for {} with " +
"id '{}'", writeOperationHelper, uploadId);
}
/**
* Upload a block of data.
* This will take the block
* @param block block to upload
* @throws IOException upload failure
*/
private void uploadBlockAsync(final S3ADataBlocks.DataBlock block)
throws IOException {
LOG.debug("Queueing upload of {}", block);
final int size = block.dataSize();
final S3ADataBlocks.BlockUploadData uploadData = block.startUpload();
final int currentPartNumber = partETagsFutures.size() + 1;
final UploadPartRequest request =
writeOperationHelper.newUploadPartRequest(
uploadId,
currentPartNumber,
size,
uploadData.getUploadStream(),
uploadData.getFile());
long transferQueueTime = now();
BlockUploadProgress callback =
new BlockUploadProgress(
block, progressListener, transferQueueTime);
request.setGeneralProgressListener(callback);
statistics.blockUploadQueued(block.dataSize());
ListenableFuture<PartETag> partETagFuture =
executorService.submit(new Callable<PartETag>() {
@Override
public PartETag call() throws Exception {
// this is the queued upload operation
LOG.debug("Uploading part {} for id '{}'", currentPartNumber,
uploadId);
// do the upload
PartETag partETag;
try {
partETag = fs.uploadPart(request).getPartETag();
LOG.debug("Completed upload of {} to part {}", block,
partETag.getETag());
LOG.debug("Stream statistics of {}", statistics);
} finally {
// close the stream and block
closeAll(LOG, uploadData, block);
}
return partETag;
}
});
partETagsFutures.add(partETagFuture);
}
/**
* Block awaiting all outstanding uploads to complete.
* @return list of results
* @throws IOException IO Problems
*/
private List<PartETag> waitForAllPartUploads() throws IOException {
LOG.debug("Waiting for {} uploads to complete", partETagsFutures.size());
try {
return Futures.allAsList(partETagsFutures).get();
} catch (InterruptedException ie) {
LOG.warn("Interrupted partUpload", ie);
Thread.currentThread().interrupt();
return null;
} catch (ExecutionException ee) {
//there is no way of recovering so abort
//cancel all partUploads
LOG.debug("While waiting for upload completion", ee);
LOG.debug("Cancelling futures");
for (ListenableFuture<PartETag> future : partETagsFutures) {
future.cancel(true);
}
//abort multipartupload
this.abort();
throw extractException("Multi-part upload with id '" + uploadId
+ "' to " + key, key, ee);
}
}
/**
* This completes a multipart upload.
* Sometimes it fails; here retries are handled to avoid losing all data
* on a transient failure.
* @param partETags list of partial uploads
* @throws IOException on any problem
*/
private CompleteMultipartUploadResult complete(List<PartETag> partETags)
throws IOException {
int retryCount = 0;
AmazonClientException lastException;
String operation =
String.format("Completing multi-part upload for key '%s'," +
" id '%s' with %s partitions ",
key, uploadId, partETags.size());
do {
try {
LOG.debug(operation);
return writeOperationHelper.completeMultipartUpload(
uploadId,
partETags);
} catch (AmazonClientException e) {
lastException = e;
statistics.exceptionInMultipartComplete();
}
} while (shouldRetry(operation, lastException, retryCount++));
// this point is only reached if the operation failed more than
// the allowed retry count
throw translateException(operation, key, lastException);
}
/**
* Abort a multi-part upload. Retries are attempted on failures.
* IOExceptions are caught; this is expected to be run as a cleanup process.
*/
public void abort() {
int retryCount = 0;
AmazonClientException lastException;
fs.incrementStatistic(OBJECT_MULTIPART_UPLOAD_ABORTED);
String operation =
String.format("Aborting multi-part upload for '%s', id '%s",
writeOperationHelper, uploadId);
do {
try {
LOG.debug(operation);
writeOperationHelper.abortMultipartUpload(uploadId);
return;
} catch (AmazonClientException e) {
lastException = e;
statistics.exceptionInMultipartAbort();
}
} while (shouldRetry(operation, lastException, retryCount++));
// this point is only reached if the operation failed more than
// the allowed retry count
LOG.warn("Unable to abort multipart upload, you may need to purge " +
"uploaded parts", lastException);
}
/**
* Predicate to determine whether a failed operation should
* be attempted again.
* If a retry is advised, the exception is automatically logged and
* the filesystem statistic {@link Statistic#IGNORED_ERRORS} incremented.
* The method then sleeps for the sleep time suggested by the sleep policy;
* if the sleep is interrupted then {@code Thread.interrupted()} is set
* to indicate the thread was interrupted; then false is returned.
*
* @param operation operation for log message
* @param e exception raised.
* @param retryCount number of retries already attempted
* @return true if another attempt should be made
*/
private boolean shouldRetry(String operation,
AmazonClientException e,
int retryCount) {
try {
RetryPolicy.RetryAction retryAction =
retryPolicy.shouldRetry(e, retryCount, 0, true);
boolean retry = retryAction == RetryPolicy.RetryAction.RETRY;
if (retry) {
fs.incrementStatistic(IGNORED_ERRORS);
LOG.info("Retrying {} after exception ", operation, e);
Thread.sleep(retryAction.delayMillis);
}
return retry;
} catch (InterruptedException ex) {
Thread.currentThread().interrupt();
return false;
} catch (Exception ignored) {
return false;
}
}
}
/**
* The upload progress listener registered for events returned
* during the upload of a single block.
* It updates statistics and handles the end of the upload.
* Transfer failures are logged at WARN.
*/
private final class BlockUploadProgress implements ProgressListener {
private final S3ADataBlocks.DataBlock block;
private final ProgressListener nextListener;
private final long transferQueueTime;
private long transferStartTime;
/**
* Track the progress of a single block upload.
* @param block block to monitor
* @param nextListener optional next progress listener
* @param transferQueueTime time the block was transferred
* into the queue
*/
private BlockUploadProgress(S3ADataBlocks.DataBlock block,
ProgressListener nextListener,
long transferQueueTime) {
this.block = block;
this.transferQueueTime = transferQueueTime;
this.nextListener = nextListener;
}
@Override
public void progressChanged(ProgressEvent progressEvent) {
ProgressEventType eventType = progressEvent.getEventType();
long bytesTransferred = progressEvent.getBytesTransferred();
int size = block.dataSize();
switch (eventType) {
case REQUEST_BYTE_TRANSFER_EVENT:
// bytes uploaded
statistics.bytesTransferred(bytesTransferred);
break;
case TRANSFER_PART_STARTED_EVENT:
transferStartTime = now();
statistics.blockUploadStarted(transferStartTime - transferQueueTime,
size);
incrementWriteOperations();
break;
case TRANSFER_PART_COMPLETED_EVENT:
statistics.blockUploadCompleted(now() - transferStartTime, size);
break;
case TRANSFER_PART_FAILED_EVENT:
statistics.blockUploadFailed(now() - transferStartTime, size);
LOG.warn("Transfer failure of block {}", block);
break;
default:
// nothing
}
if (nextListener != null) {
nextListener.progressChanged(progressEvent);
}
}
}
/**
* Bridge from AWS {@code ProgressListener} to Hadoop {@link Progressable}.
*/
private static class ProgressableListener implements ProgressListener {
private final Progressable progress;
public ProgressableListener(Progressable progress) {
this.progress = progress;
}
public void progressChanged(ProgressEvent progressEvent) {
if (progress != null) {
progress.progress();
}
}
}
}