org.apache.storm.hdfs.spout.TestDirLock.java Source code

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Here is the source code for org.apache.storm.hdfs.spout.TestDirLock.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
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * 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.storm.hdfs.spout;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CommonConfigurationKeys;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.junit.After;
import org.junit.AfterClass;
import org.junit.Assert;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;

import java.io.IOException;

public class TestDirLock {

    static MiniDFSCluster.Builder builder;
    static MiniDFSCluster hdfsCluster;
    static FileSystem fs;
    static String hdfsURI;
    static HdfsConfiguration conf = new HdfsConfiguration();
    static final int LOCK_EXPIRY_SEC = 1;
    private Path locksDir = new Path("/tmp/lockdir");

    @BeforeClass
    public static void setupClass() throws IOException {
        conf.set(CommonConfigurationKeys.IPC_PING_INTERVAL_KEY, "5000");
        builder = new MiniDFSCluster.Builder(new Configuration());
        hdfsCluster = builder.build();
        fs = hdfsCluster.getFileSystem();
        hdfsURI = "hdfs://localhost:" + hdfsCluster.getNameNodePort() + "/";
    }

    @AfterClass
    public static void teardownClass() throws IOException {
        fs.close();
        hdfsCluster.shutdown();
    }

    @Before
    public void setUp() throws Exception {
        assert fs.mkdirs(locksDir);
    }

    @After
    public void tearDown() throws Exception {
        fs.delete(locksDir, true);
    }

    @Test
    public void testBasicLocking() throws Exception {
        // 1 grab lock
        DirLock lock = DirLock.tryLock(fs, locksDir);
        Assert.assertTrue(fs.exists(lock.getLockFile()));

        // 2 try to grab another lock while dir is locked
        DirLock lock2 = DirLock.tryLock(fs, locksDir); // should fail
        Assert.assertNull(lock2);

        // 3 let go first lock
        lock.release();
        Assert.assertFalse(fs.exists(lock.getLockFile()));

        // 4 try locking again
        lock2 = DirLock.tryLock(fs, locksDir);
        Assert.assertTrue(fs.exists(lock2.getLockFile()));
        lock2.release();
        Assert.assertFalse(fs.exists(lock.getLockFile()));
        lock2.release(); // should be throw
    }

    @Test
    public void testConcurrentLocking() throws Exception {
        DirLockingThread[] thds = startThreads(100, locksDir);
        for (DirLockingThread thd : thds) {
            thd.join();
            if (!thd.cleanExit) {
                System.err.println(thd.getName() + " did not exit cleanly");
            }
            Assert.assertTrue(thd.cleanExit);
        }

        Path lockFile = new Path(locksDir + Path.SEPARATOR + DirLock.DIR_LOCK_FILE);
        Assert.assertFalse(fs.exists(lockFile));
    }

    private DirLockingThread[] startThreads(int thdCount, Path dir) throws IOException {
        DirLockingThread[] result = new DirLockingThread[thdCount];
        for (int i = 0; i < thdCount; i++) {
            result[i] = new DirLockingThread(i, fs, dir);
        }

        for (DirLockingThread thd : result) {
            thd.start();
        }
        return result;
    }

    @Test
    public void testLockRecovery() throws Exception {
        DirLock lock1 = DirLock.tryLock(fs, locksDir); // should pass
        Assert.assertNotNull(lock1);

        DirLock lock2 = DirLock.takeOwnershipIfStale(fs, locksDir, LOCK_EXPIRY_SEC); // should fail
        Assert.assertNull(lock2);

        Thread.sleep(LOCK_EXPIRY_SEC * 1000 + 500); // wait for lock to expire
        Assert.assertTrue(fs.exists(lock1.getLockFile()));

        DirLock lock3 = DirLock.takeOwnershipIfStale(fs, locksDir, LOCK_EXPIRY_SEC); // should pass now
        Assert.assertNotNull(lock3);
        Assert.assertTrue(fs.exists(lock3.getLockFile()));
        lock3.release();
        Assert.assertFalse(fs.exists(lock3.getLockFile()));
        lock1.release(); // should not throw
    }

    class DirLockingThread extends Thread {

        private int thdNum;
        private final FileSystem fs;
        private final Path dir;
        public boolean cleanExit = false;

        public DirLockingThread(int thdNum, FileSystem fs, Path dir) throws IOException {
            this.thdNum = thdNum;
            this.fs = fs;
            this.dir = dir;
        }

        @Override
        public void run() {
            Thread.currentThread().setName("DirLockingThread-" + thdNum);
            DirLock lock = null;
            try {
                do {
                    System.err.println("Trying lock " + getName());
                    lock = DirLock.tryLock(fs, dir);
                    System.err.println("Acquired lock " + getName());
                    if (lock == null) {
                        System.out.println("Retrying lock - " + getName());
                    }
                } while (lock == null);
                cleanExit = true;
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                try {
                    if (lock != null) {
                        lock.release();
                        System.err.println("Released lock " + getName());
                    }
                } catch (IOException e) {
                    e.printStackTrace(System.err);
                }
            }
            System.err.println("Thread exiting " + getName());
        } // run()

    } // class DirLockingThread
}