Java tutorial
/* * Copyright 2011-2014 Proofpoint, Inc. * * 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://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 com.proofpoint.event.collector.combiner; import com.amazonaws.AmazonClientException; import com.amazonaws.services.s3.AmazonS3; import com.amazonaws.services.s3.model.AmazonS3Exception; import com.amazonaws.services.s3.model.ObjectMetadata; import com.google.common.base.Charsets; import com.proofpoint.event.collector.EventPartition; import com.proofpoint.event.collector.ServerConfig; import com.proofpoint.json.JsonCodec; import com.proofpoint.log.Logger; import org.apache.commons.codec.binary.Base64; import org.apache.commons.codec.digest.DigestUtils; import javax.inject.Inject; import javax.ws.rs.core.MediaType; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.net.URI; import static com.google.common.base.Preconditions.checkArgument; import static com.google.common.base.Preconditions.checkNotNull; import static com.proofpoint.event.collector.combiner.S3StorageHelper.getS3Bucket; import static com.proofpoint.event.collector.combiner.S3StorageHelper.getS3ObjectKey; public class S3CombineObjectMetadataStore implements CombineObjectMetadataStore { private static final Logger log = Logger.get(S3CombineObjectMetadataStore.class); private final JsonCodec<CombinedGroup> jsonCodec = JsonCodec.jsonCodec(CombinedGroup.class); private final AmazonS3 s3Service; private final URI storageArea; @Inject public S3CombineObjectMetadataStore(ServerConfig config, AmazonS3 s3Service) { this(URI.create(checkNotNull(config, "config is null").getS3MetadataLocation()), s3Service); } public S3CombineObjectMetadataStore(URI storageArea, AmazonS3 s3Service) { this.storageArea = checkNotNull(storageArea, "storageArea is null"); this.s3Service = checkNotNull(s3Service, "s3Service is null"); } @Override public CombinedGroup getCombinedGroupManifest(EventPartition eventPartition, String sizeName) { return readMetadataFile(eventPartition, sizeName); } @Override public boolean replaceCombinedGroupManifest(EventPartition eventPartition, String sizeName, CombinedGroup currentGroup, CombinedGroup newGroup) { checkNotNull(currentGroup, "currentGroup is null"); checkNotNull(newGroup, "newGroup is null"); checkArgument(currentGroup.getLocationPrefix().equals(newGroup.getLocationPrefix()), "newGroup location is different from currentGroup location"); CombinedGroup persistentGroup = readMetadataFile(eventPartition, sizeName); if (persistentGroup != null) { if (persistentGroup.getVersion() != currentGroup.getVersion()) { return false; } } else if (currentGroup.getVersion() != 0) { return false; } return writeMetadataFile(eventPartition, newGroup, sizeName); } private boolean writeMetadataFile(EventPartition eventPartition, CombinedGroup combinedGroup, String sizeName) { byte[] json = jsonCodec.toJson(combinedGroup).getBytes(Charsets.UTF_8); URI metadataFile = toMetadataLocation(eventPartition, sizeName); try { ObjectMetadata metadata = new ObjectMetadata(); metadata.setContentLength(json.length); metadata.setContentMD5(Base64.encodeBase64String(DigestUtils.md5(json))); metadata.setContentType(MediaType.APPLICATION_JSON); InputStream input = new ByteArrayInputStream(json); s3Service.putObject(getS3Bucket(metadataFile), getS3ObjectKey(metadataFile), input, metadata); return true; } catch (AmazonClientException e) { log.warn(e, "error writing metadata file: %s", metadataFile); return false; } } private URI toMetadataLocation(EventPartition eventPartition, String sizeName) { return storageArea.resolve(eventPartition.getEventType() + "/" + eventPartition.getMajorTimeBucket() + "/" + eventPartition.getMinorTimeBucket() + "." + sizeName + ".metadata"); } private CombinedGroup readMetadataFile(EventPartition eventPartition, String sizeName) { URI metadataFile = toMetadataLocation(eventPartition, sizeName); String json; try { json = new S3InputSupplier(s3Service, metadataFile).asCharSource(Charsets.UTF_8).read(); } catch (IOException e) { if (e.getCause() instanceof AmazonS3Exception) { if ("NoSuchKey".equals(((AmazonS3Exception) e.getCause()).getErrorCode())) { return null; } } throw new RuntimeException( "Could not load metadata at " + metadataFile + " file for " + eventPartition + " " + sizeName); } try { return jsonCodec.fromJson(json); } catch (IllegalArgumentException e) { throw new RuntimeException( "Metadata at " + metadataFile + " file for " + eventPartition + " " + sizeName + " is corrupt"); } } }