| /** |
| * 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.hadoop.hdfs; |
| |
| import static org.junit.Assert.assertEquals; |
| |
| import java.io.File; |
| import java.net.URI; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.fs.Path; |
| import org.apache.hadoop.hdfs.protocol.HdfsConstants.SafeModeAction; |
| import org.apache.hadoop.hdfs.tools.DFSAdmin; |
| import org.apache.hadoop.hdfs.util.MD5FileUtils; |
| import org.apache.hadoop.io.MD5Hash; |
| import org.junit.Test; |
| |
| public class TestFetchImage { |
| |
| private static File FETCHED_IMAGE_FILE = new File( |
| System.getProperty("build.test.dir"), "fetched-image-dir"); |
| // Shamelessly stolen from NNStorage. |
| private static final Pattern IMAGE_REGEX = Pattern.compile("fsimage_(\\d+)"); |
| |
| /** |
| * Download a few fsimages using `hdfs dfsadmin -fetchImage ...' and verify |
| * the results. |
| */ |
| @Test |
| public void testFetchImage() throws Exception { |
| FETCHED_IMAGE_FILE.mkdirs(); |
| Configuration conf = new Configuration(); |
| MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build(); |
| FileSystem fs = null; |
| try { |
| DFSAdmin dfsAdmin = new DFSAdmin(); |
| dfsAdmin.setConf(conf); |
| |
| runFetchImage(dfsAdmin, cluster); |
| |
| fs = cluster.getFileSystem(); |
| fs.mkdirs(new Path("/foo")); |
| fs.mkdirs(new Path("/foo2")); |
| fs.mkdirs(new Path("/foo3")); |
| |
| cluster.getNameNodeRpc().setSafeMode(SafeModeAction.SAFEMODE_ENTER); |
| cluster.getNameNodeRpc().saveNamespace(); |
| cluster.getNameNodeRpc().setSafeMode(SafeModeAction.SAFEMODE_LEAVE); |
| |
| runFetchImage(dfsAdmin, cluster); |
| } finally { |
| if (fs != null) { |
| fs.close(); |
| } |
| if (cluster != null) { |
| cluster.shutdown(); |
| } |
| } |
| } |
| |
| /** |
| * Run `hdfs dfsadmin -fetchImage ...' and verify that the downloaded image is |
| * correct. |
| */ |
| private static void runFetchImage(DFSAdmin dfsAdmin, MiniDFSCluster cluster) |
| throws Exception { |
| int retVal = dfsAdmin.run(new String[]{"-fetchImage", |
| FETCHED_IMAGE_FILE.getPath() }); |
| |
| assertEquals(0, retVal); |
| |
| File highestImageOnNn = getHighestFsImageOnCluster(cluster); |
| MD5Hash expected = MD5FileUtils.computeMd5ForFile(highestImageOnNn); |
| MD5Hash actual = MD5FileUtils.computeMd5ForFile( |
| new File(FETCHED_IMAGE_FILE, highestImageOnNn.getName())); |
| |
| assertEquals(expected, actual); |
| } |
| |
| /** |
| * @return the fsimage with highest transaction ID in the cluster. |
| */ |
| private static File getHighestFsImageOnCluster(MiniDFSCluster cluster) { |
| long highestImageTxId = -1; |
| File highestImageOnNn = null; |
| for (URI nameDir : cluster.getNameDirs(0)) { |
| for (File imageFile : new File(new File(nameDir), "current").listFiles()) { |
| Matcher imageMatch = IMAGE_REGEX.matcher(imageFile.getName()); |
| if (imageMatch.matches()) { |
| long imageTxId = Long.valueOf(imageMatch.group(1)); |
| if (imageTxId > highestImageTxId) { |
| highestImageTxId = imageTxId; |
| highestImageOnNn = imageFile; |
| } |
| } |
| } |
| } |
| return highestImageOnNn; |
| } |
| } |