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.jackrabbit.oak.blob.cloud.aws.s3; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.util.Properties; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.amazonaws.AmazonClientException; import com.amazonaws.ClientConfiguration; import com.amazonaws.Protocol; import com.amazonaws.auth.AWSCredentials; import com.amazonaws.auth.BasicAWSCredentials; import com.amazonaws.regions.Regions; import com.amazonaws.services.s3.model.Region; import com.amazonaws.services.s3.AmazonS3; import com.amazonaws.services.s3.AmazonS3Client; import com.amazonaws.services.s3.model.ObjectListing; import com.amazonaws.services.s3.model.S3ObjectSummary; import com.amazonaws.util.StringUtils; /** * Amazon S3 utilities. */ public final class Utils { private static final Logger LOG = LoggerFactory.getLogger(Utils.class); public static final String DEFAULT_CONFIG_FILE = "aws.properties"; private static final String DELETE_CONFIG_SUFFIX = ";burn"; /** * The default value AWS bucket region. */ public static final String DEFAULT_AWS_BUCKET_REGION = "us-standard"; /** * constants to define endpoint to various AWS region */ public static final String AWSDOTCOM = "amazonaws.com"; public static final String S3 = "s3"; public static final String DOT = "."; public static final String DASH = "-"; /** * private constructor so that class cannot initialized from outside. */ private Utils() { } /** * Create AmazonS3Client from properties. * * @param prop properties to configure @link {@link AmazonS3Client} * @return {@link AmazonS3Client} */ public static AmazonS3Client openService(final Properties prop) { String accessKey = prop.getProperty(S3Constants.ACCESS_KEY); String secretKey = prop.getProperty(S3Constants.SECRET_KEY); AmazonS3Client s3service = null; if (StringUtils.isNullOrEmpty(accessKey) || StringUtils.isNullOrEmpty(secretKey)) { LOG.info("Configuring Amazon Client from environment"); s3service = new AmazonS3Client(getClientConfiguration(prop)); } else { LOG.info("Configuring Amazon Client from property file."); AWSCredentials credentials = new BasicAWSCredentials(accessKey, secretKey); s3service = new AmazonS3Client(credentials, getClientConfiguration(prop)); } String region = prop.getProperty(S3Constants.S3_REGION); String endpoint = null; String propEndPoint = prop.getProperty(S3Constants.S3_END_POINT); if ((propEndPoint != null) & !"".equals(propEndPoint)) { endpoint = propEndPoint; } else { if (StringUtils.isNullOrEmpty(region)) { com.amazonaws.regions.Region s3Region = Regions.getCurrentRegion(); if (s3Region != null) { region = s3Region.getName(); } else { throw new AmazonClientException("parameter [" + S3Constants.S3_REGION + "] not configured and cannot be derived from environment"); } } if (DEFAULT_AWS_BUCKET_REGION.equals(region)) { endpoint = S3 + DOT + AWSDOTCOM; } else if (Region.EU_Ireland.toString().equals(region)) { endpoint = "s3-eu-west-1" + DOT + AWSDOTCOM; } else { endpoint = S3 + DASH + region + DOT + AWSDOTCOM; } } /* * setting endpoint to remove latency of redirection. If endpoint is * not set, invocation first goes us standard region, which * redirects it to correct location. */ s3service.setEndpoint(endpoint); LOG.info("S3 service endpoint [{}] ", endpoint); return s3service; } /** * Delete S3 bucket. This method first deletes all objects from bucket and * then delete empty bucket. * * @param bucketName the bucket name. */ public static void deleteBucket(final String bucketName) throws IOException { Properties prop = readConfig(DEFAULT_CONFIG_FILE); AmazonS3 s3service = openService(prop); ObjectListing prevObjectListing = s3service.listObjects(bucketName); while (true) { for (S3ObjectSummary s3ObjSumm : prevObjectListing.getObjectSummaries()) { s3service.deleteObject(bucketName, s3ObjSumm.getKey()); } if (!prevObjectListing.isTruncated()) { break; } prevObjectListing = s3service.listNextBatchOfObjects(prevObjectListing); } s3service.deleteBucket(bucketName); } /** * Read a configuration properties file. If the file name ends with ";burn", * the file is deleted after reading. * * @param fileName the properties file name * @return the properties * @throws java.io.IOException if the file doesn't exist */ public static Properties readConfig(String fileName) throws IOException { boolean delete = false; if (fileName.endsWith(DELETE_CONFIG_SUFFIX)) { delete = true; fileName = fileName.substring(0, fileName.length() - DELETE_CONFIG_SUFFIX.length()); } if (!new File(fileName).exists()) { throw new IOException("Config file not found: " + fileName); } Properties prop = new Properties(); InputStream in = null; try { in = new FileInputStream(fileName); prop.load(in); } finally { if (in != null) { in.close(); } if (delete) { deleteIfPossible(new File(fileName)); } } return prop; } private static void deleteIfPossible(final File file) { boolean deleted = file.delete(); if (!deleted) { LOG.warn("Could not delete " + file.getAbsolutePath()); } } private static ClientConfiguration getClientConfiguration(Properties prop) { int connectionTimeOut = Integer.parseInt(prop.getProperty(S3Constants.S3_CONN_TIMEOUT)); int socketTimeOut = Integer.parseInt(prop.getProperty(S3Constants.S3_SOCK_TIMEOUT)); int maxConnections = Integer.parseInt(prop.getProperty(S3Constants.S3_MAX_CONNS)); int maxErrorRetry = Integer.parseInt(prop.getProperty(S3Constants.S3_MAX_ERR_RETRY)); String protocol = prop.getProperty(S3Constants.S3_CONN_PROTOCOL); String proxyHost = prop.getProperty(S3Constants.PROXY_HOST); String proxyPort = prop.getProperty(S3Constants.PROXY_PORT); ClientConfiguration cc = new ClientConfiguration(); if (protocol != null && protocol.equalsIgnoreCase("http")) { cc.setProtocol(Protocol.HTTP); } if (proxyHost != null && !proxyHost.isEmpty()) { cc.setProxyHost(proxyHost); } if (proxyPort != null && !proxyPort.isEmpty()) { cc.setProxyPort(Integer.parseInt(proxyPort)); } cc.setConnectionTimeout(connectionTimeOut); cc.setSocketTimeout(socketTimeOut); cc.setMaxConnections(maxConnections); cc.setMaxErrorRetry(maxErrorRetry); return cc; } }