/**
* 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.curator.framework.recipes.cache;
import org.apache.curator.utils.CloseableUtils;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.api.UnhandledErrorListener;
import org.apache.curator.framework.recipes.BaseClassForTests;
import org.apache.curator.retry.RetryOneTime;
import org.apache.curator.test.KillSession;
import org.apache.curator.test.Timing;
import org.testng.Assert;
import org.testng.annotations.Test;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Exchanger;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;
public class TestNodeCache extends BaseClassForTests
{
@Test
public void testDeleteThenCreate() throws Exception
{
NodeCache cache = null;
CuratorFramework client = CuratorFrameworkFactory.newClient(server.getConnectString(), new RetryOneTime(1));
client.start();
try
{
client.create().creatingParentsIfNeeded().forPath("/test/foo", "one".getBytes());
final AtomicReference<Throwable> error = new AtomicReference<Throwable>();
client.getUnhandledErrorListenable().addListener
(
new UnhandledErrorListener()
{
@Override
public void unhandledError(String message, Throwable e)
{
error.set(e);
}
}
);
final Semaphore semaphore = new Semaphore(0);
cache = new NodeCache(client, "/test/foo");
cache.getListenable().addListener
(
new NodeCacheListener()
{
@Override
public void nodeChanged() throws Exception
{
semaphore.release();
}
}
);
cache.start(true);
Assert.assertEquals(cache.getCurrentData().getData(), "one".getBytes());
client.delete().forPath("/test/foo");
Assert.assertTrue(semaphore.tryAcquire(1, 10, TimeUnit.SECONDS));
client.create().forPath("/test/foo", "two".getBytes());
Assert.assertTrue(semaphore.tryAcquire(1, 10, TimeUnit.SECONDS));
Throwable t = error.get();
if ( t != null )
{
Assert.fail("Assert", t);
}
Assert.assertEquals(cache.getCurrentData().getData(), "two".getBytes());
cache.close();
}
finally
{
CloseableUtils.closeQuietly(cache);
CloseableUtils.closeQuietly(client);
}
}
@Test
public void testRebuildAgainstOtherProcesses() throws Exception
{
NodeCache cache = null;
final CuratorFramework client = CuratorFrameworkFactory.newClient(server.getConnectString(), new RetryOneTime(1));
client.start();
try
{
client.create().forPath("/test");
client.create().forPath("/test/snafu", "original".getBytes());
final CountDownLatch latch = new CountDownLatch(1);
cache = new NodeCache(client, "/test/snafu");
cache.getListenable().addListener
(
new NodeCacheListener()
{
@Override
public void nodeChanged() throws Exception
{
latch.countDown();
}
}
);
cache.rebuildTestExchanger = new Exchanger<Object>();
ExecutorService service = Executors.newSingleThreadExecutor();
final NodeCache finalCache = cache;
Future<Object> future = service.submit
(
new Callable<Object>()
{
@Override
public Object call() throws Exception
{
finalCache.rebuildTestExchanger.exchange(new Object(), 10, TimeUnit.SECONDS);
// simulate another process updating the node while we're rebuilding
client.setData().forPath("/test/snafu", "other".getBytes());
ChildData currentData = finalCache.getCurrentData();
Assert.assertNotNull(currentData);
finalCache.rebuildTestExchanger.exchange(new Object(), 10, TimeUnit.SECONDS);
return null;
}
}
);
cache.start(false);
future.get();
Assert.assertTrue(latch.await(10, TimeUnit.SECONDS));
Assert.assertNotNull(cache.getCurrentData());
Assert.assertEquals(cache.getCurrentData().getData(), "other".getBytes());
}
finally
{
CloseableUtils.closeQuietly(cache);
CloseableUtils.closeQuietly(client);
}
}
@Test
public void testKilledSession() throws Exception
{
NodeCache cache = null;
Timing timing = new Timing();
CuratorFramework client = null;
try
{
client = CuratorFrameworkFactory.newClient(server.getConnectString(), timing.session(), timing.connection(), new RetryOneTime(1));
client.start();
client.create().creatingParentsIfNeeded().forPath("/test/node", "start".getBytes());
cache = new NodeCache(client, "/test/node");
cache.start(true);
final CountDownLatch latch = new CountDownLatch(1);
cache.getListenable().addListener
(
new NodeCacheListener()
{
@Override
public void nodeChanged() throws Exception
{
latch.countDown();
}
}
);
KillSession.kill(client.getZookeeperClient().getZooKeeper(), server.getConnectString());
Thread.sleep(timing.multiple(1.5).session());
Assert.assertEquals(cache.getCurrentData().getData(), "start".getBytes());
client.setData().forPath("/test/node", "new data".getBytes());
Assert.assertTrue(timing.awaitLatch(latch));
}
finally
{
CloseableUtils.closeQuietly(cache);
CloseableUtils.closeQuietly(client);
}
}
@Test
public void testBasics() throws Exception
{
NodeCache cache = null;
Timing timing = new Timing();
CuratorFramework client = CuratorFrameworkFactory.newClient(server.getConnectString(), timing.session(), timing.connection(), new RetryOneTime(1));
client.start();
try
{
client.create().forPath("/test");
cache = new NodeCache(client, "/test/node");
cache.start(true);
final Semaphore semaphore = new Semaphore(0);
cache.getListenable().addListener
(
new NodeCacheListener()
{
@Override
public void nodeChanged() throws Exception
{
semaphore.release();
}
}
);
Assert.assertNull(cache.getCurrentData());
client.create().forPath("/test/node", "a".getBytes());
Assert.assertTrue(timing.acquireSemaphore(semaphore));
Assert.assertEquals(cache.getCurrentData().getData(), "a".getBytes());
client.setData().forPath("/test/node", "b".getBytes());
Assert.assertTrue(timing.acquireSemaphore(semaphore));
Assert.assertEquals(cache.getCurrentData().getData(), "b".getBytes());
client.delete().forPath("/test/node");
Assert.assertTrue(timing.acquireSemaphore(semaphore));
Assert.assertNull(cache.getCurrentData());
}
finally
{
CloseableUtils.closeQuietly(cache);
CloseableUtils.closeQuietly(client);
}
}
}