Java tutorial
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See the License for the * specific language governing permissions and limitations * under the License. */ package org.elasticsearch.repositories.s3; import com.amazonaws.services.s3.AmazonS3; import com.amazonaws.services.s3.model.CannedAccessControlList; import com.amazonaws.services.s3.model.DeleteObjectsRequest; import com.amazonaws.services.s3.model.DeleteObjectsRequest.KeyVersion; import com.amazonaws.services.s3.model.ObjectListing; import com.amazonaws.services.s3.model.S3ObjectSummary; import com.amazonaws.services.s3.model.StorageClass; import org.elasticsearch.common.blobstore.BlobContainer; import org.elasticsearch.common.blobstore.BlobPath; import org.elasticsearch.common.blobstore.BlobStore; import org.elasticsearch.common.blobstore.BlobStoreException; import org.elasticsearch.common.component.AbstractComponent; import org.elasticsearch.common.settings.Settings; import org.elasticsearch.common.unit.ByteSizeValue; import java.security.AccessController; import java.security.PrivilegedAction; import java.util.ArrayList; import java.util.Locale; class S3BlobStore extends AbstractComponent implements BlobStore { private final AmazonS3 client; private final String bucket; private final ByteSizeValue bufferSize; private final boolean serverSideEncryption; private final CannedAccessControlList cannedACL; private final StorageClass storageClass; S3BlobStore(Settings settings, AmazonS3 client, String bucket, boolean serverSideEncryption, ByteSizeValue bufferSize, String cannedACL, String storageClass) { super(settings); this.client = client; this.bucket = bucket; this.serverSideEncryption = serverSideEncryption; this.bufferSize = bufferSize; this.cannedACL = initCannedACL(cannedACL); this.storageClass = initStorageClass(storageClass); // Note: the method client.doesBucketExist() may return 'true' is the bucket exists // but we don't have access to it (ie, 403 Forbidden response code) // Also, if invalid security credentials are used to execute this method, the // client is not able to distinguish between bucket permission errors and // invalid credential errors, and this method could return an incorrect result. SocketAccess.doPrivilegedVoid(() -> { if (client.doesBucketExist(bucket) == false) { throw new IllegalArgumentException( "The bucket [" + bucket + "] does not exist. Please create it before " + " creating an s3 snapshot repository backed by it."); } }); } @Override public String toString() { return bucket; } public AmazonS3 client() { return client; } public String bucket() { return bucket; } public boolean serverSideEncryption() { return serverSideEncryption; } public int bufferSizeInBytes() { return bufferSize.bytesAsInt(); } @Override public BlobContainer blobContainer(BlobPath path) { return new S3BlobContainer(path, this); } @Override public void delete(BlobPath path) { AccessController.doPrivileged((PrivilegedAction<Object>) () -> { ObjectListing prevListing = null; //From http://docs.amazonwebservices.com/AmazonS3/latest/dev/DeletingMultipleObjectsUsingJava.html //we can do at most 1K objects per delete //We don't know the bucket name until first object listing DeleteObjectsRequest multiObjectDeleteRequest = null; ArrayList<KeyVersion> keys = new ArrayList<>(); while (true) { ObjectListing list; if (prevListing != null) { list = client.listNextBatchOfObjects(prevListing); } else { list = client.listObjects(bucket, path.buildAsString()); multiObjectDeleteRequest = new DeleteObjectsRequest(list.getBucketName()); } for (S3ObjectSummary summary : list.getObjectSummaries()) { keys.add(new KeyVersion(summary.getKey())); //Every 500 objects batch the delete request if (keys.size() > 500) { multiObjectDeleteRequest.setKeys(keys); client.deleteObjects(multiObjectDeleteRequest); multiObjectDeleteRequest = new DeleteObjectsRequest(list.getBucketName()); keys.clear(); } } if (list.isTruncated()) { prevListing = list; } else { break; } } if (!keys.isEmpty()) { multiObjectDeleteRequest.setKeys(keys); client.deleteObjects(multiObjectDeleteRequest); } return null; }); } @Override public void close() { } public CannedAccessControlList getCannedACL() { return cannedACL; } public StorageClass getStorageClass() { return storageClass; } public static StorageClass initStorageClass(String storageClass) { if (storageClass == null || storageClass.equals("")) { return StorageClass.Standard; } try { StorageClass _storageClass = StorageClass.fromValue(storageClass.toUpperCase(Locale.ENGLISH)); if (_storageClass.equals(StorageClass.Glacier)) { throw new BlobStoreException("Glacier storage class is not supported"); } return _storageClass; } catch (IllegalArgumentException illegalArgumentException) { throw new BlobStoreException("`" + storageClass + "` is not a valid S3 Storage Class."); } } /** * Constructs canned acl from string */ public static CannedAccessControlList initCannedACL(String cannedACL) { if (cannedACL == null || cannedACL.equals("")) { return CannedAccessControlList.Private; } for (CannedAccessControlList cur : CannedAccessControlList.values()) { if (cur.toString().equalsIgnoreCase(cannedACL)) { return cur; } } throw new BlobStoreException("cannedACL is not valid: [" + cannedACL + "]"); } }