org.apache.hadoop.hdfs.server.datanode.TestDataNodeUUID.java Source code

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Here is the source code for org.apache.hadoop.hdfs.server.datanode.TestDataNodeUUID.java

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/**
 * 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.server.datanode;

import org.apache.commons.io.FileUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.junit.Test;

import java.io.File;
import java.net.InetSocketAddress;
import java.util.ArrayList;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;
import static org.junit.Assert.assertTrue;

public class TestDataNodeUUID {

    /**
     * This test makes sure that we have a valid
     * Node ID after the checkNodeUUID is done.
     */
    @Test
    public void testDatanodeUuid() throws Exception {

        final InetSocketAddress NN_ADDR = new InetSocketAddress("localhost", 5020);
        Configuration conf = new HdfsConfiguration();
        conf.set(DFSConfigKeys.DFS_DATANODE_ADDRESS_KEY, "0.0.0.0:0");
        conf.set(DFSConfigKeys.DFS_DATANODE_HTTP_ADDRESS_KEY, "0.0.0.0:0");
        conf.set(DFSConfigKeys.DFS_DATANODE_IPC_ADDRESS_KEY, "0.0.0.0:0");
        FileSystem.setDefaultUri(conf, "hdfs://" + NN_ADDR.getHostName() + ":" + NN_ADDR.getPort());
        ArrayList<StorageLocation> locations = new ArrayList<>();

        DataNode dn = new DataNode(conf, locations, null);

        //Assert that Node iD is null
        String nullString = null;
        assertEquals(dn.getDatanodeUuid(), nullString);

        // CheckDataNodeUUID will create an UUID if UUID is null
        dn.checkDatanodeUuid();

        // Make sure that we have a valid DataNodeUUID at that point of time.
        assertNotEquals(dn.getDatanodeUuid(), nullString);
    }

    @Test(timeout = 10000)
    public void testUUIDRegeneration() throws Exception {
        File baseDir = new File(System.getProperty("test.build.data"));
        File disk1 = new File(baseDir, "disk1");
        File disk2 = new File(baseDir, "disk2");

        // Ensure the configured disks do not pre-exist
        FileUtils.deleteDirectory(disk1);
        FileUtils.deleteDirectory(disk2);

        MiniDFSCluster cluster = null;
        HdfsConfiguration conf = new HdfsConfiguration();
        conf.setStrings(DFSConfigKeys.DFS_DATANODE_DATA_DIR_KEY, disk1.toURI().toString(),
                disk2.toURI().toString());
        try {
            cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).manageDataDfsDirs(false).build();
            cluster.waitActive();

            // Grab the new-cluster UUID as the original one to test against
            String originalUUID = cluster.getDataNodes().get(0).getDatanodeUuid();
            // Stop and simulate a DN wipe or unmount-but-root-path condition
            // on the second disk
            MiniDFSCluster.DataNodeProperties dn = cluster.stopDataNode(0);
            FileUtils.deleteDirectory(disk2);
            assertTrue("Failed to recreate the data directory: " + disk2, disk2.mkdirs());

            // Restart and check if the UUID changed
            assertTrue("DataNode failed to start up: " + dn, cluster.restartDataNode(dn));
            // We need to wait until the DN has completed registration
            while (!cluster.getDataNodes().get(0).isDatanodeFullyStarted()) {
                Thread.sleep(50);
            }
            assertEquals("DN generated a new UUID despite disk1 having it intact", originalUUID,
                    cluster.getDataNodes().get(0).getDatanodeUuid());
        } finally {
            if (cluster != null) {
                cluster.shutdown();
            }
        }
    }
}