Java tutorial
/* * 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.druid.storage.s3; import com.amazonaws.AmazonServiceException; import com.amazonaws.services.s3.model.CopyObjectRequest; import com.amazonaws.services.s3.model.ListObjectsV2Request; import com.amazonaws.services.s3.model.ListObjectsV2Result; import com.amazonaws.services.s3.model.S3ObjectSummary; import com.amazonaws.services.s3.model.StorageClass; import com.google.common.base.Predicate; import com.google.common.base.Throwables; import com.google.common.collect.ImmutableMap; import com.google.common.collect.Maps; import com.google.inject.Inject; import org.apache.druid.java.util.common.IOE; import org.apache.druid.java.util.common.ISE; import org.apache.druid.java.util.common.MapUtils; import org.apache.druid.java.util.common.RetryUtils; import org.apache.druid.java.util.common.StringUtils; import org.apache.druid.java.util.common.logger.Logger; import org.apache.druid.segment.loading.DataSegmentMover; import org.apache.druid.segment.loading.DataSegmentPusher; import org.apache.druid.segment.loading.SegmentLoadingException; import org.apache.druid.timeline.DataSegment; import java.io.IOException; import java.util.Map; public class S3DataSegmentMover implements DataSegmentMover { private static final Logger log = new Logger(S3DataSegmentMover.class); private final ServerSideEncryptingAmazonS3 s3Client; private final S3DataSegmentPusherConfig config; @Inject public S3DataSegmentMover(ServerSideEncryptingAmazonS3 s3Client, S3DataSegmentPusherConfig config) { this.s3Client = s3Client; this.config = config; } @Override public DataSegment move(DataSegment segment, Map<String, Object> targetLoadSpec) throws SegmentLoadingException { try { Map<String, Object> loadSpec = segment.getLoadSpec(); String s3Bucket = MapUtils.getString(loadSpec, "bucket"); String s3Path = MapUtils.getString(loadSpec, "key"); String s3DescriptorPath = S3Utils.descriptorPathForSegmentPath(s3Path); final String targetS3Bucket = MapUtils.getString(targetLoadSpec, "bucket"); final String targetS3BaseKey = MapUtils.getString(targetLoadSpec, "baseKey"); final String targetS3Path = S3Utils.constructSegmentPath(targetS3BaseKey, DataSegmentPusher.getDefaultStorageDir(segment, false)); final String targetS3DescriptorPath = S3Utils.descriptorPathForSegmentPath(targetS3Path); if (targetS3Bucket.isEmpty()) { throw new SegmentLoadingException("Target S3 bucket is not specified"); } if (targetS3Path.isEmpty()) { throw new SegmentLoadingException("Target S3 baseKey is not specified"); } safeMove(s3Bucket, s3Path, targetS3Bucket, targetS3Path); safeMove(s3Bucket, s3DescriptorPath, targetS3Bucket, targetS3DescriptorPath); return segment.withLoadSpec(ImmutableMap.<String, Object>builder() .putAll(Maps.filterKeys(loadSpec, new Predicate<String>() { @Override public boolean apply(String input) { return !("bucket".equals(input) || "key".equals(input)); } })).put("bucket", targetS3Bucket).put("key", targetS3Path).build()); } catch (AmazonServiceException e) { throw new SegmentLoadingException(e, "Unable to move segment[%s]: [%s]", segment.getIdentifier(), e); } } private void safeMove(final String s3Bucket, final String s3Path, final String targetS3Bucket, final String targetS3Path) throws SegmentLoadingException { try { S3Utils.retryS3Operation(() -> { final String copyMsg = StringUtils.format("[s3://%s/%s] to [s3://%s/%s]", s3Bucket, s3Path, targetS3Bucket, targetS3Path); try { selfCheckingMove(s3Bucket, targetS3Bucket, s3Path, targetS3Path, copyMsg); return null; } catch (AmazonServiceException | IOException | SegmentLoadingException e) { log.info(e, "Error while trying to move " + copyMsg); throw e; } }); } catch (Exception e) { Throwables.propagateIfInstanceOf(e, AmazonServiceException.class); Throwables.propagateIfInstanceOf(e, SegmentLoadingException.class); throw Throwables.propagate(e); } } /** * Copies an object and after that checks that the object is present at the target location, via a separate API call. * If it is not, an exception is thrown, and the object is not deleted at the old location. This "paranoic" check * is added after it was observed that S3 may report a successful move, and the object is not found at the target * location. */ private void selfCheckingMove(String s3Bucket, String targetS3Bucket, String s3Path, String targetS3Path, String copyMsg) throws IOException, SegmentLoadingException { if (s3Bucket.equals(targetS3Bucket) && s3Path.equals(targetS3Path)) { log.info("No need to move file[s3://%s/%s] onto itself", s3Bucket, s3Path); return; } if (s3Client.doesObjectExist(s3Bucket, s3Path)) { final ListObjectsV2Result listResult = s3Client.listObjectsV2( new ListObjectsV2Request().withBucketName(s3Bucket).withPrefix(s3Path).withMaxKeys(1)); if (listResult.getKeyCount() == 0) { // should never happen throw new ISE("Unable to list object [s3://%s/%s]", s3Bucket, s3Path); } final S3ObjectSummary objectSummary = listResult.getObjectSummaries().get(0); if (objectSummary.getStorageClass() != null && StorageClass.fromValue(StringUtils.toUpperCase(objectSummary.getStorageClass())) .equals(StorageClass.Glacier)) { throw new AmazonServiceException(StringUtils.format( "Cannot move file[s3://%s/%s] of storage class glacier, skipping.", s3Bucket, s3Path)); } else { log.info("Moving file %s", copyMsg); final CopyObjectRequest copyRequest = new CopyObjectRequest(s3Bucket, s3Path, targetS3Bucket, targetS3Path); if (!config.getDisableAcl()) { copyRequest .setAccessControlList(S3Utils.grantFullControlToBucketOwner(s3Client, targetS3Bucket)); } s3Client.copyObject(copyRequest); if (!s3Client.doesObjectExist(targetS3Bucket, targetS3Path)) { throw new IOE( "After copy was reported as successful the file doesn't exist in the target location [%s]", copyMsg); } deleteWithRetriesSilent(s3Bucket, s3Path); log.debug("Finished moving file %s", copyMsg); } } else { // ensure object exists in target location if (s3Client.doesObjectExist(targetS3Bucket, targetS3Path)) { log.info("Not moving file [s3://%s/%s], already present in target location [s3://%s/%s]", s3Bucket, s3Path, targetS3Bucket, targetS3Path); } else { throw new SegmentLoadingException( "Unable to move file %s, not present in either source or target location", copyMsg); } } } private void deleteWithRetriesSilent(final String s3Bucket, final String s3Path) { try { deleteWithRetries(s3Bucket, s3Path); } catch (Exception e) { log.error(e, "Failed to delete file [s3://%s/%s], giving up", s3Bucket, s3Path); } } private void deleteWithRetries(final String s3Bucket, final String s3Path) throws Exception { RetryUtils.retry(() -> { try { s3Client.deleteObject(s3Bucket, s3Path); return null; } catch (Exception e) { log.info(e, "Error while trying to delete [s3://%s/%s]", s3Bucket, s3Path); throw e; } }, S3Utils.S3RETRY, 3); } }