/*
* Copyright 2011-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* 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://aws.amazon.com/apache2.0
*
* This file 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 com.amazonaws.mobileconnectors.s3.transfermanager.internal;
import com.amazonaws.AmazonClientException;
import com.amazonaws.event.ProgressEvent;
import com.amazonaws.event.ProgressListenerCallbackExecutor;
import com.amazonaws.event.ProgressListenerChain;
import com.amazonaws.mobileconnectors.s3.transfermanager.Transfer.TransferState;
import com.amazonaws.mobileconnectors.s3.transfermanager.TransferManager;
import com.amazonaws.mobileconnectors.s3.transfermanager.model.CopyResult;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.model.CompleteMultipartUploadRequest;
import com.amazonaws.services.s3.model.CompleteMultipartUploadResult;
import com.amazonaws.services.s3.model.CopyObjectRequest;
import com.amazonaws.services.s3.model.PartETag;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
/**
* Monitors an copy operation by periodically checking to see if the operation
* is completed, and returning a result if so. Otherwise, schedules a copy of
* itself to be run in the future. When waiting on the result of this class via
* a Future object, clients must call {@link CopyMonitor#isDone()} and
* {@link CopyMonitor#getFuture()}
*/
public class CopyMonitor implements Callable<CopyResult>, TransferMonitor {
/**
* Reference to the Amazon S3 client object that is used to initiate the
* copy or copy part request.
*/
private final AmazonS3 s3;
/** Thread pool used during multi-part copy is performed. */
private final ExecutorService threadPool;
/** A reference to the original copy request received. */
private final CopyObjectRequest copyObjectRequest;
/**
* Thread pool used for scheduling the monitor to check if the copy
* operation is completed.
*/
private ScheduledExecutorService timedThreadPool;
/** Reference to the CopyCallable that is used for initiating copy requests. */
private final CopyCallable multipartCopyCallable;
private final CopyImpl transfer;
private final ProgressListenerCallbackExecutor progressListenerChainCallbackExecutor;
/*
* State for tracking the upload's progress
*/
private String uploadId;
private final List<Future<PartETag>> futures = new ArrayList<Future<PartETag>>();
/*
* State for clients wishing to poll for completion
*/
private boolean isCopyDone = false;
private Future<CopyResult> nextFuture;
@Override
public synchronized Future<CopyResult> getFuture() {
return nextFuture;
}
private synchronized void setNextFuture(Future<CopyResult> nextFuture) {
this.nextFuture = nextFuture;
}
@Override
public synchronized boolean isDone() {
return isCopyDone;
}
private synchronized void markAllDone() {
isCopyDone = true;
}
// TODO: this could be configured in the configuration object (which we're
// not using right now)
private int pollInterval = 5000;
/**
* Constructs a new watcher for copy operation, which immediately submits
* itself to the thread pool.
*
* @param manager The {@link TransferManager} that owns this copy request.
* @param threadPool The {@link ExecutorService} to which we should submit
* new tasks.
* @param multipartCopyCallable The callable responsible for processing the
* copy asynchronously
* @param copyObjectRequest The original CopyObject request
*/
public CopyMonitor(TransferManager manager, CopyImpl transfer,
ExecutorService threadPool, CopyCallable multipartCopyCallable,
CopyObjectRequest copyObjectRequest,
ProgressListenerChain progressListenerChain) {
this.s3 = manager.getAmazonS3Client();
this.multipartCopyCallable = multipartCopyCallable;
this.threadPool = threadPool;
this.copyObjectRequest = copyObjectRequest;
this.transfer = transfer;
this.progressListenerChainCallbackExecutor = ProgressListenerCallbackExecutor
.wrapListener(progressListenerChain);
setNextFuture(threadPool.submit(this));
}
@Override
public CopyResult call() throws Exception {
try {
if (uploadId == null) {
return copy();
} else {
return poll();
}
} catch (CancellationException e) {
transfer.setState(TransferState.Canceled);
fireProgressEvent(ProgressEvent.CANCELED_EVENT_CODE);
throw new AmazonClientException("Upload canceled");
} catch (Exception e) {
transfer.setState(TransferState.Failed);
fireProgressEvent(ProgressEvent.FAILED_EVENT_CODE);
throw e;
}
}
public void setTimedThreadPool(ScheduledExecutorService timedThreadPool) {
this.timedThreadPool = timedThreadPool;
}
/**
* Polls for a result from a multi-part copy operation and either returns it
* if complete, or reschedules to poll again later if not.
*/
private CopyResult poll() throws InterruptedException {
for (Future<PartETag> f : futures) {
if (!f.isDone()) {
reschedule();
return null;
}
}
for (Future<PartETag> f : futures) {
if (f.isCancelled()) {
throw new CancellationException();
}
}
return completeMultipartUpload();
}
private void fireProgressEvent(final int eventType) {
if (progressListenerChainCallbackExecutor == null)
return;
ProgressEvent event = new ProgressEvent(0);
event.setEventCode(eventType);
progressListenerChainCallbackExecutor.progressChanged(event);
}
/**
* Initiates the copy operation and checks on the result. If it has
* completed, returns the result; otherwise, reschedules to check back
* later.
*/
private CopyResult copy() throws Exception, InterruptedException {
CopyResult result = multipartCopyCallable.call();
if (result != null) {
copyComplete();
} else {
uploadId = multipartCopyCallable.getMultipartUploadId();
futures.addAll(multipartCopyCallable.getFutures());
reschedule();
}
return result;
}
private void copyComplete() {
markAllDone();
transfer.setState(TransferState.Completed);
// AmazonS3Client takes care of all the events for single part uploads,
// so we only need to send a completed event for multipart uploads.
if (multipartCopyCallable.isMultipartCopy()) {
fireProgressEvent(ProgressEvent.COMPLETED_EVENT_CODE);
}
}
private void reschedule() {
setNextFuture(timedThreadPool.schedule(new Callable<CopyResult>() {
@Override
public CopyResult call() throws Exception {
setNextFuture(threadPool.submit(CopyMonitor.this));
return null;
}
}, pollInterval, TimeUnit.MILLISECONDS));
}
/**
* Completes the multipart upload and returns the result.
*/
private CopyResult completeMultipartUpload() {
CompleteMultipartUploadResult completeMultipartUploadResult = s3
.completeMultipartUpload(new CompleteMultipartUploadRequest(
copyObjectRequest.getDestinationBucketName(),
copyObjectRequest.getDestinationKey(), uploadId,
collectPartETags()));
copyComplete();
CopyResult copyResult = new CopyResult();
copyResult.setSourceBucketName(copyObjectRequest.getSourceBucketName());
copyResult.setSourceKey(copyObjectRequest.getSourceKey());
copyResult.setDestinationBucketName(completeMultipartUploadResult
.getBucketName());
copyResult.setDestinationKey(completeMultipartUploadResult.getKey());
copyResult.setETag(completeMultipartUploadResult.getETag());
copyResult.setVersionId(completeMultipartUploadResult.getVersionId());
return copyResult;
}
private List<PartETag> collectPartETags() {
final List<PartETag> partETags = new ArrayList<PartETag>(futures.size());
for (Future<PartETag> future : futures) {
try {
partETags.add(future.get());
} catch (Exception e) {
throw new AmazonClientException("Unable to copy part: "
+ e.getCause().getMessage(), e.getCause());
}
}
return partETags;
}
}