/**
*
* 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.hbase.zookeeper;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import java.io.IOException;
import java.lang.reflect.Method;
import java.util.Random;
import java.util.concurrent.Semaphore;
import junit.framework.Assert;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.HConnectionManager;
import org.apache.hadoop.hbase.master.TestActiveMasterManager.NodeDeletionListener;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.Threads;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;
import org.junit.experimental.categories.Category;
@Category(MediumTests.class)
public class TestZooKeeperNodeTracker {
private static final Log LOG = LogFactory.getLog(TestZooKeeperNodeTracker.class);
private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
private final static Random rand = new Random();
@BeforeClass
public static void setUpBeforeClass() throws Exception {
TEST_UTIL.startMiniZKCluster();
}
@AfterClass
public static void tearDownAfterClass() throws Exception {
TEST_UTIL.shutdownMiniZKCluster();
}
/**
* Test that we can interrupt a node that is blocked on a wait.
* @throws IOException
* @throws InterruptedException
*/
@Test public void testInterruptible() throws IOException, InterruptedException {
Abortable abortable = new StubAbortable();
ZooKeeperWatcher zk = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
"testInterruptible", abortable);
final TestTracker tracker = new TestTracker(zk, "/xyz", abortable);
tracker.start();
Thread t = new Thread() {
@Override
public void run() {
try {
tracker.blockUntilAvailable();
} catch (InterruptedException e) {
throw new RuntimeException("Interrupted", e);
}
}
};
t.start();
while (!t.isAlive()) Threads.sleep(1);
tracker.stop();
t.join();
// If it wasn't interruptible, we'd never get to here.
}
@Test
public void testNodeTracker() throws Exception {
Abortable abortable = new StubAbortable();
ZooKeeperWatcher zk = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
"testNodeTracker", abortable);
ZKUtil.createAndFailSilent(zk, zk.baseZNode);
final String node =
ZKUtil.joinZNode(zk.baseZNode, new Long(rand.nextLong()).toString());
final byte [] dataOne = Bytes.toBytes("dataOne");
final byte [] dataTwo = Bytes.toBytes("dataTwo");
// Start a ZKNT with no node currently available
TestTracker localTracker = new TestTracker(zk, node, abortable);
localTracker.start();
zk.registerListener(localTracker);
// Make sure we don't have a node
assertNull(localTracker.getData(false));
// Spin up a thread with another ZKNT and have it block
WaitToGetDataThread thread = new WaitToGetDataThread(zk, node);
thread.start();
// Verify the thread doesn't have a node
assertFalse(thread.hasData);
// Now, start a new ZKNT with the node already available
TestTracker secondTracker = new TestTracker(zk, node, null);
secondTracker.start();
zk.registerListener(secondTracker);
// Put up an additional zk listener so we know when zk event is done
TestingZKListener zkListener = new TestingZKListener(zk, node);
zk.registerListener(zkListener);
assertEquals(0, zkListener.createdLock.availablePermits());
// Create a completely separate zk connection for test triggers and avoid
// any weird watcher interactions from the test
final ZooKeeper zkconn = new ZooKeeper(
ZKConfig.getZKQuorumServersString(TEST_UTIL.getConfiguration()), 60000,
new StubWatcher());
// Add the node with data one
zkconn.create(node, dataOne, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
// Wait for the zk event to be processed
zkListener.waitForCreation();
thread.join();
// Both trackers should have the node available with data one
assertNotNull(localTracker.getData(false));
assertNotNull(localTracker.blockUntilAvailable());
assertTrue(Bytes.equals(localTracker.getData(false), dataOne));
assertTrue(thread.hasData);
assertTrue(Bytes.equals(thread.tracker.getData(false), dataOne));
LOG.info("Successfully got data one");
// Make sure it's available and with the expected data
assertNotNull(secondTracker.getData(false));
assertNotNull(secondTracker.blockUntilAvailable());
assertTrue(Bytes.equals(secondTracker.getData(false), dataOne));
LOG.info("Successfully got data one with the second tracker");
// Drop the node
zkconn.delete(node, -1);
zkListener.waitForDeletion();
// Create a new thread but with the existing thread's tracker to wait
TestTracker threadTracker = thread.tracker;
thread = new WaitToGetDataThread(zk, node, threadTracker);
thread.start();
// Verify other guys don't have data
assertFalse(thread.hasData);
assertNull(secondTracker.getData(false));
assertNull(localTracker.getData(false));
LOG.info("Successfully made unavailable");
// Create with second data
zkconn.create(node, dataTwo, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
// Wait for the zk event to be processed
zkListener.waitForCreation();
thread.join();
// All trackers should have the node available with data two
assertNotNull(localTracker.getData(false));
assertNotNull(localTracker.blockUntilAvailable());
assertTrue(Bytes.equals(localTracker.getData(false), dataTwo));
assertNotNull(secondTracker.getData(false));
assertNotNull(secondTracker.blockUntilAvailable());
assertTrue(Bytes.equals(secondTracker.getData(false), dataTwo));
assertTrue(thread.hasData);
assertTrue(Bytes.equals(thread.tracker.getData(false), dataTwo));
LOG.info("Successfully got data two on all trackers and threads");
// Change the data back to data one
zkconn.setData(node, dataOne, -1);
// Wait for zk event to be processed
zkListener.waitForDataChange();
// All trackers should have the node available with data one
assertNotNull(localTracker.getData(false));
assertNotNull(localTracker.blockUntilAvailable());
assertTrue(Bytes.equals(localTracker.getData(false), dataOne));
assertNotNull(secondTracker.getData(false));
assertNotNull(secondTracker.blockUntilAvailable());
assertTrue(Bytes.equals(secondTracker.getData(false), dataOne));
assertTrue(thread.hasData);
assertTrue(Bytes.equals(thread.tracker.getData(false), dataOne));
LOG.info("Successfully got data one following a data change on all trackers and threads");
}
public static class WaitToGetDataThread extends Thread {
TestTracker tracker;
boolean hasData;
public WaitToGetDataThread(ZooKeeperWatcher zk, String node) {
tracker = new TestTracker(zk, node, null);
tracker.start();
zk.registerListener(tracker);
hasData = false;
}
public WaitToGetDataThread(ZooKeeperWatcher zk, String node,
TestTracker tracker) {
this.tracker = tracker;
hasData = false;
}
@Override
public void run() {
LOG.info("Waiting for data to be available in WaitToGetDataThread");
try {
tracker.blockUntilAvailable();
} catch (InterruptedException e) {
e.printStackTrace();
}
LOG.info("Data now available in tracker from WaitToGetDataThread");
hasData = true;
}
}
public static class TestTracker extends ZooKeeperNodeTracker {
public TestTracker(ZooKeeperWatcher watcher, String node,
Abortable abortable) {
super(watcher, node, abortable);
}
}
public static class TestingZKListener extends ZooKeeperListener {
private static final Log LOG = LogFactory.getLog(NodeDeletionListener.class);
private Semaphore deletedLock;
private Semaphore createdLock;
private Semaphore changedLock;
private String node;
public TestingZKListener(ZooKeeperWatcher watcher, String node) {
super(watcher);
deletedLock = new Semaphore(0);
createdLock = new Semaphore(0);
changedLock = new Semaphore(0);
this.node = node;
}
@Override
public void nodeDeleted(String path) {
if(path.equals(node)) {
LOG.debug("nodeDeleted(" + path + ")");
deletedLock.release();
}
}
@Override
public void nodeCreated(String path) {
if(path.equals(node)) {
LOG.debug("nodeCreated(" + path + ")");
createdLock.release();
}
}
@Override
public void nodeDataChanged(String path) {
if(path.equals(node)) {
LOG.debug("nodeDataChanged(" + path + ")");
changedLock.release();
}
}
public void waitForDeletion() throws InterruptedException {
deletedLock.acquire();
}
public void waitForCreation() throws InterruptedException {
createdLock.acquire();
}
public void waitForDataChange() throws InterruptedException {
changedLock.acquire();
}
}
public static class StubAbortable implements Abortable {
@Override
public void abort(final String msg, final Throwable t) {}
@Override
public boolean isAborted() {
return false;
}
}
public static class StubWatcher implements Watcher {
@Override
public void process(WatchedEvent event) {}
}
@Test
public void testCleanZNode() throws Exception {
ZooKeeperWatcher zkw = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
"testNodeTracker", new TestZooKeeperNodeTracker.StubAbortable());
final ServerName sn = new ServerName("127.0.0.1:52",45L);
ZKUtil.createAndFailSilent(zkw,
TEST_UTIL.getConfiguration().get(HConstants.ZOOKEEPER_ZNODE_PARENT,
HConstants.DEFAULT_ZOOKEEPER_ZNODE_PARENT));
final String nodeName = zkw.getMasterAddressZNode();
// Check that we manage the case when there is no data
ZKUtil.createAndFailSilent(zkw, nodeName);
MasterAddressTracker.deleteIfEquals(zkw, sn.toString());
Assert.assertFalse(ZKUtil.getData(zkw, nodeName) == null);
// Check that we don't delete if we're not supposed to
ZKUtil.setData(zkw, nodeName, MasterAddressTracker.toByteArray(sn));
MasterAddressTracker.deleteIfEquals(zkw, new ServerName("127.0.0.2:52",45L).toString());
Assert.assertFalse(ZKUtil.getData(zkw, nodeName) == null);
// Check that we delete when we're supposed to
ZKUtil.setData(zkw, nodeName,MasterAddressTracker.toByteArray(sn));
MasterAddressTracker.deleteIfEquals(zkw, sn.toString());
Assert.assertTrue( ZKUtil.getData(zkw, nodeName)== null );
// Check that we support the case when the znode does not exist
MasterAddressTracker.deleteIfEquals(zkw, sn.toString()); // must not throw an exception
}
}