content: /*
   * 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.distributedlog.impl;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  
  import com.google.common.collect.Sets;
  import java.net.URI;
  import java.util.Iterator;
  import java.util.Set;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.atomic.AtomicInteger;
  import java.util.concurrent.atomic.AtomicReference;
  import org.apache.bookkeeper.common.util.OrderedScheduler;
  import org.apache.distributedlog.DistributedLogConfiguration;
  import org.apache.distributedlog.TestDistributedLogBase;
  import org.apache.distributedlog.TestZooKeeperClientBuilder;
  import org.apache.distributedlog.ZooKeeperClient;
  import org.apache.distributedlog.ZooKeeperClientUtils;
  import org.apache.distributedlog.callback.NamespaceListener;
  import org.apache.distributedlog.util.Utils;
  import org.apache.zookeeper.CreateMode;
  import org.apache.zookeeper.ZooDefs;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.TestName;
  
  
  
  /**
   * Test ZK Namespace Watcher.
   */
  public class TestZKNamespaceWatcher extends TestDistributedLogBase {
  
      private static final  int zkSessionTimeoutMs = 2000;
  
      @Rule
      public TestName runtime = new TestName();
      protected final DistributedLogConfiguration baseConf =
              new DistributedLogConfiguration();
      protected ZooKeeperClient zkc;
      protected OrderedScheduler scheduler;
  
      @Before
      public void setup() throws Exception {
          zkc = TestZooKeeperClientBuilder.newBuilder()
                  .uri(createDLMURI("/"))
                  .sessionTimeoutMs(zkSessionTimeoutMs)
                  .build();
          scheduler = OrderedScheduler.newSchedulerBuilder()
                  .name("test-zk-namespace-watcher")
                  .numThreads(1)
                  .build();
      }
  
      @After
      public void teardown() throws Exception {
          if (null != zkc) {
              zkc.close();
          }
          if (null != scheduler) {
              scheduler.shutdown();
          }
      }
  
      private void createLogInNamespace(URI uri, String logName) throws Exception {
          String logPath = uri.getPath() + "/" + logName;
          Utils.zkCreateFullPathOptimistic(zkc, logPath, new byte[0],
                  ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
      }
  
      private void deleteLogInNamespace(URI uri, String logName) throws Exception {
          String logPath = uri.getPath() + "/" + logName;
          zkc.get().delete(logPath, -1);
      }
  
      @Test(timeout = 60000)
      public void testNamespaceListener() throws Exception {
          URI uri = createDLMURI("/" + runtime.getMethodName());
          zkc.get().create(uri.getPath(), new byte[0], ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
          DistributedLogConfiguration conf = new DistributedLogConfiguration();
          conf.addConfiguration(baseConf);
          ZKNamespaceWatcher watcher = new ZKNamespaceWatcher(conf, uri, zkc, scheduler);
          final CountDownLatch[] latches = new CountDownLatch[10];
          for (int i = 0; i < 10; i++) {
              latches[i] = new CountDownLatch(1);
          }
          final AtomicInteger numUpdates = new AtomicInteger(0);
          final AtomicReference<Set<String>> receivedLogs = new AtomicReference<Set<String>>(null);
          watcher.registerListener(new NamespaceListener() {
              @Override
              public void onStreamsChanged(Iterator<String> streams) {
                  Set<String> streamSet = Sets.newHashSet(streams);
                  int updates = numUpdates.incrementAndGet();
                  receivedLogs.set(streamSet);
                  latches[updates - 1].countDown();
              }
          });
          // first update
          final Set<String> expectedLogs = Sets.newHashSet();
          latches[0].await();
          validateReceivedLogs(expectedLogs, receivedLogs.get());
  
          // create test1
          expectedLogs.add("test1");
          createLogInNamespace(uri, "test1");
          latches[1].await();
          validateReceivedLogs(expectedLogs, receivedLogs.get());
  
          // create invalid log
          createLogInNamespace(uri, ".test1");
          latches[2].await();
          validateReceivedLogs(expectedLogs, receivedLogs.get());
  
          // create test2
          expectedLogs.add("test2");
          createLogInNamespace(uri, "test2");
          latches[3].await();
          validateReceivedLogs(expectedLogs, receivedLogs.get());
  
          // delete test1
          expectedLogs.remove("test1");
          deleteLogInNamespace(uri, "test1");
          latches[4].await();
          validateReceivedLogs(expectedLogs, receivedLogs.get());
      }
  
      private void validateReceivedLogs(Set<String> expectedLogs, Set<String> receivedLogs) {
          assertTrue(Sets.difference(expectedLogs, receivedLogs).isEmpty());
      }
  
      @Test(timeout = 60000)
      public void testSessionExpired() throws Exception {
          URI uri = createDLMURI("/" + runtime.getMethodName());
          zkc.get().create(uri.getPath(), new byte[0], ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
          DistributedLogConfiguration conf = new DistributedLogConfiguration();
          conf.addConfiguration(baseConf);
          ZKNamespaceWatcher watcher = new ZKNamespaceWatcher(conf, uri, zkc, scheduler);
          final CountDownLatch[] latches = new CountDownLatch[10];
          for (int i = 0; i < 10; i++) {
              latches[i] = new CountDownLatch(1);
          }
          final AtomicInteger numUpdates = new AtomicInteger(0);
          final AtomicReference<Set<String>> receivedLogs = new AtomicReference<Set<String>>(null);
          watcher.registerListener(new NamespaceListener() {
              @Override
              public void onStreamsChanged(Iterator<String> streams) {
                  Set<String> streamSet = Sets.newHashSet(streams);
                  int updates = numUpdates.incrementAndGet();
                  receivedLogs.set(streamSet);
                  latches[updates - 1].countDown();
              }
          });
          latches[0].await();
          createLogInNamespace(uri, "test1");
          latches[1].await();
          createLogInNamespace(uri, "test2");
          latches[2].await();
          assertEquals(2, receivedLogs.get().size());
          ZooKeeperClientUtils.expireSession(zkc, BKNamespaceDriver.getZKServersFromDLUri(uri), zkSessionTimeoutMs);
          latches[3].await();
          assertEquals(2, receivedLogs.get().size());
          createLogInNamespace(uri, "test3");
          latches[4].await();
          assertEquals(3, receivedLogs.get().size());
      }
  
  }
  