001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.zookeeper;
019
020import static org.junit.Assert.assertTrue;
021
022import java.io.IOException;
023import java.lang.reflect.Field;
024import org.apache.hadoop.conf.Configuration;
025import org.apache.hadoop.hbase.Abortable;
026import org.apache.hadoop.hbase.HBaseClassTestRule;
027import org.apache.hadoop.hbase.HBaseZKTestingUtility;
028import org.apache.hadoop.hbase.HConstants;
029import org.apache.hadoop.hbase.testclassification.MediumTests;
030import org.apache.hadoop.hbase.testclassification.ZKTests;
031import org.apache.hadoop.hbase.util.Bytes;
032import org.apache.zookeeper.CreateMode;
033import org.apache.zookeeper.KeeperException;
034import org.apache.zookeeper.Watcher;
035import org.apache.zookeeper.ZooDefs.Ids;
036import org.apache.zookeeper.ZooKeeper;
037import org.apache.zookeeper.data.Stat;
038import org.junit.AfterClass;
039import org.junit.BeforeClass;
040import org.junit.ClassRule;
041import org.junit.Test;
042import org.junit.experimental.categories.Category;
043
044@Category({ ZKTests.class, MediumTests.class })
045public class TestRecoverableZooKeeper {
046
047  @ClassRule
048  public static final HBaseClassTestRule CLASS_RULE =
049      HBaseClassTestRule.forClass(TestRecoverableZooKeeper.class);
050
051  private final static HBaseZKTestingUtility TEST_UTIL = new HBaseZKTestingUtility();
052
053  Abortable abortable = new Abortable() {
054    @Override
055    public void abort(String why, Throwable e) {
056
057    }
058
059    @Override
060    public boolean isAborted() {
061      return false;
062    }
063  };
064
065  @BeforeClass
066  public static void setUpBeforeClass() throws Exception {
067    TEST_UTIL.startMiniZKCluster();
068  }
069
070  @AfterClass
071  public static void tearDownAfterClass() throws Exception {
072    TEST_UTIL.shutdownMiniZKCluster();
073  }
074
075  @Test
076  public void testSetDataVersionMismatchInLoop() throws Exception {
077    String znode = "/hbase/splitWAL/9af7cfc9b15910a0b3d714bf40a3248f";
078    Configuration conf = TEST_UTIL.getConfiguration();
079    ZKWatcher zkw = new ZKWatcher(conf, "testSetDataVersionMismatchInLoop",
080        abortable, true);
081    String ensemble = ZKConfig.getZKQuorumServersString(conf);
082    RecoverableZooKeeper rzk = ZKUtil.connect(conf, ensemble, zkw);
083    rzk.create(znode, new byte[0], Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
084    rzk.setData(znode, "OPENING".getBytes(), 0);
085    Field zkField = RecoverableZooKeeper.class.getDeclaredField("zk");
086    zkField.setAccessible(true);
087    int timeout = conf.getInt(HConstants.ZK_SESSION_TIMEOUT, HConstants.DEFAULT_ZK_SESSION_TIMEOUT);
088    ZookeeperStub zkStub = new ZookeeperStub(ensemble, timeout, zkw);
089    zkStub.setThrowExceptionInNumOperations(1);
090    zkField.set(rzk, zkStub);
091    byte[] opened = "OPENED".getBytes();
092    rzk.setData(znode, opened, 1);
093    byte[] data = rzk.getData(znode, false, new Stat());
094    assertTrue(Bytes.equals(opened, data));
095  }
096
097  class ZookeeperStub extends ZooKeeper {
098
099    private int throwExceptionInNumOperations;
100
101    public ZookeeperStub(String connectString, int sessionTimeout, Watcher watcher)
102        throws IOException {
103      super(connectString, sessionTimeout, watcher);
104    }
105
106    public void setThrowExceptionInNumOperations(int throwExceptionInNumOperations) {
107      this.throwExceptionInNumOperations = throwExceptionInNumOperations;
108    }
109
110    private void checkThrowKeeperException() throws KeeperException {
111      if (throwExceptionInNumOperations == 1) {
112        throwExceptionInNumOperations = 0;
113        throw new KeeperException.ConnectionLossException();
114      }
115      if (throwExceptionInNumOperations > 0) {
116        throwExceptionInNumOperations--;
117      }
118    }
119
120    @Override
121    public Stat setData(String path, byte[] data, int version) throws KeeperException,
122        InterruptedException {
123      Stat stat = super.setData(path, data, version);
124      checkThrowKeeperException();
125      return stat;
126    }
127  }
128}