/** @see com.amazonaws.http.HttpResponseHandler#handle(com.amazonaws.http.HttpResponse) */
public AmazonWebServiceResponse<S3Object> handle(HttpResponse response) throws Exception {
/*
* TODO: It'd be nice to set the bucket name and key here, but the
* information isn't easy to pull out of the response/request
* currently.
*/
S3Object object = new S3Object();
AmazonWebServiceResponse<S3Object> awsResponse = parseResponseMetadata(response);
if (response.getHeaders().get(Headers.REDIRECT_LOCATION) != null) {
object.setRedirectLocation(response.getHeaders().get(Headers.REDIRECT_LOCATION));
}
ObjectMetadata metadata = object.getObjectMetadata();
populateObjectMetadata(response, metadata);
boolean hasServerSideCalculatedChecksum =
!ServiceUtils.isMultipartUploadETag(metadata.getETag());
boolean responseContainsEntireObject = response.getHeaders().get("Content-Range") == null;
if (hasServerSideCalculatedChecksum && responseContainsEntireObject) {
byte[] expectedChecksum = BinaryUtils.fromHex(metadata.getETag());
object.setObjectContent(
new S3ObjectInputStream(
new ChecksumValidatingInputStream(
response.getContent(),
expectedChecksum,
object.getBucketName() + "/" + object.getKey()),
response.getHttpRequest()));
} else {
object.setObjectContent(
new S3ObjectInputStream(response.getContent(), response.getHttpRequest()));
}
awsResponse.setResult(object);
return awsResponse;
}
/**
* Downloads an S3Object, as returned from {@link
* AmazonS3Client#getObject(com.amazonaws.services.s3.model.GetObjectRequest)}, to the specified
* file.
*
* @param s3Object The S3Object containing a reference to an InputStream containing the object's
* data.
* @param destinationFile The file to store the object's data in.
* @param performIntegrityCheck Boolean valuable to indicate whether do the integrity check or not
*/
public static void downloadObjectToFile(
S3Object s3Object, File destinationFile, boolean performIntegrityCheck) {
// attempt to create the parent if it doesn't exist
File parentDirectory = destinationFile.getParentFile();
if (parentDirectory != null && !parentDirectory.exists()) {
parentDirectory.mkdirs();
}
OutputStream outputStream = null;
try {
outputStream = new BufferedOutputStream(new FileOutputStream(destinationFile));
byte[] buffer = new byte[1024 * 10];
int bytesRead;
while ((bytesRead = s3Object.getObjectContent().read(buffer)) > -1) {
outputStream.write(buffer, 0, bytesRead);
}
} catch (IOException e) {
try {
s3Object.getObjectContent().abort();
} catch (IOException abortException) {
log.warn("Couldn't abort stream", e);
}
throw new AmazonClientException(
"Unable to store object contents to disk: " + e.getMessage(), e);
} finally {
try {
outputStream.close();
} catch (Exception e) {
}
try {
s3Object.getObjectContent().close();
} catch (Exception e) {
}
}
byte[] clientSideHash = null;
byte[] serverSideHash = null;
try {
// Multipart Uploads don't have an MD5 calculated on the service side
if (ServiceUtils.isMultipartUploadETag(s3Object.getObjectMetadata().getETag()) == false) {
clientSideHash = Md5Utils.computeMD5Hash(new FileInputStream(destinationFile));
serverSideHash = BinaryUtils.fromHex(s3Object.getObjectMetadata().getETag());
}
} catch (Exception e) {
log.warn("Unable to calculate MD5 hash to validate download: " + e.getMessage(), e);
}
if (performIntegrityCheck
&& clientSideHash != null
&& serverSideHash != null
&& !Arrays.equals(clientSideHash, serverSideHash)) {
throw new AmazonClientException(
"Unable to verify integrity of data download. "
+ "Client calculated content hash didn't match hash calculated by Amazon S3. "
+ "The data stored in '"
+ destinationFile.getAbsolutePath()
+ "' may be corrupt.");
}
}
/**
* Gets an object stored in S3 and downloads it into the specified file. This method includes the
* one-time retry mechanism after integrity check failure on the downloaded file. It will also
* return immediately after getting null valued S3Object (when getObject request does not meet the
* specified constraints).
*
* @param file The file to store the object's data in.
* @param safeS3DownloadTask The implementation of SafeS3DownloadTask interface which allows user
* to get access to all the visible variables at the calling site of this method.
*/
public static S3Object retryableDownloadS3ObjectToFile(
File file, RetryableS3DownloadTask retryableS3DownloadTask) {
boolean hasRetried = false;
boolean needRetry;
S3Object s3Object;
do {
needRetry = false;
s3Object = retryableS3DownloadTask.getS3ObjectStream();
if (s3Object == null) return null;
try {
ServiceUtils.downloadObjectToFile(
s3Object, file, retryableS3DownloadTask.needIntegrityCheck());
} catch (AmazonClientException ace) {
// Determine whether an immediate retry is needed according to the captured
// AmazonClientException.
// (There are three cases when downloadObjectToFile() throws AmazonClientException:
// 1) SocketException or SSLProtocolException when writing to disk (e.g. when user aborts
// the download)
// 2) Other IOException when writing to disk
// 3) MD5 hashes don't match
// The current code will retry the download only when case 2) or 3) happens.
if (ace.getCause() instanceof SocketException
|| ace.getCause() instanceof SSLProtocolException) {
throw ace;
} else {
needRetry = true;
if (hasRetried) throw ace;
else {
log.info(
"Retry the download of object "
+ s3Object.getKey()
+ " (bucket "
+ s3Object.getBucketName()
+ ")",
ace);
hasRetried = true;
}
}
} finally {
try {
s3Object.getObjectContent().abort();
} catch (IOException e) {
}
}
} while (needRetry);
return s3Object;
}
