org.apache.twill.zookeeper.ZKClientServices Java Examples

@Provides
@Singleton
private ZKClientService provideZKClientService(Configuration conf) {
  String zkStr = conf.get(TxConstants.Service.CFG_DATA_TX_ZOOKEEPER_QUORUM);
  if (zkStr == null) {
    // Default to HBase one.
    zkStr = conf.get(TxConstants.HBase.ZOOKEEPER_QUORUM);
  }

  int timeOut = conf.getInt(TxConstants.HBase.ZK_SESSION_TIMEOUT, TxConstants.HBase.DEFAULT_ZK_SESSION_TIMEOUT);
  ZKClientService zkClientService = new TephraZKClientService(zkStr, timeOut, null,
                                                              ArrayListMultimap.<String, byte[]>create());
  return ZKClientServices.delegate(
    ZKClients.reWatchOnExpire(
      ZKClients.retryOnFailure(zkClientService, RetryStrategies.exponentialDelay(500, 2000, TimeUnit.MILLISECONDS)
      )
    )
  );
}
 

@Override
public PhoenixTransactionService getTransactionService(Configuration config, ConnectionInfo connInfo, int port) {
    config.setInt(TxConstants.Service.CFG_DATA_TX_BIND_PORT, port);
    int retryTimeOut = config.getInt(TxConstants.Service.CFG_DATA_TX_CLIENT_DISCOVERY_TIMEOUT_SEC, 
            TxConstants.Service.DEFAULT_DATA_TX_CLIENT_DISCOVERY_TIMEOUT_SEC);
    ZKClientService zkClient = ZKClientServices.delegate(
      ZKClients.reWatchOnExpire(
        ZKClients.retryOnFailure(
          ZKClientService.Builder.of(connInfo.getZookeeperConnectionString())
            .setSessionTimeout(config.getInt(HConstants.ZK_SESSION_TIMEOUT,
                    HConstants.DEFAULT_ZK_SESSION_TIMEOUT))
            .build(),
          RetryStrategies.exponentialDelay(500, retryTimeOut, TimeUnit.MILLISECONDS)
        )
      )
    );

    DiscoveryService discovery = new ZKDiscoveryService(zkClient);
    TransactionManager txManager = new TransactionManager(config, new HDFSTransactionStateStorage(config, 
            new SnapshotCodecProvider(config), new TxMetricsCollector()), new TxMetricsCollector());
    TransactionService txService = new TransactionService(config, zkClient, discovery, Providers.of(txManager));
    TephraTransactionService service = new TephraTransactionService(zkClient, txService);
    service.start();
    return service;
}
 

@BeforeClass
public static void beforeClass() {
  zkServer = InMemoryZKServer.builder().setTickTime(100000).build();
  zkServer.startAndWait();

  zkClient = ZKClientServices.delegate(
    ZKClients.retryOnFailure(
      ZKClients.reWatchOnExpire(
        ZKClientService.Builder.of(zkServer.getConnectionStr()).build()),
      RetryStrategies.fixDelay(1, TimeUnit.SECONDS)));
  zkClient.startAndWait();
}
 

/**
 * Creates a {@link ZKClientService}.
 */
protected final ZKClientService createZKClient() {
  TwillRuntimeSpecification twillRuntimeSpec = getTwillRuntimeSpecification();

  return ZKClientServices.delegate(
    ZKClients.namespace(
      ZKClients.reWatchOnExpire(
        ZKClients.retryOnFailure(
          ZKClientService.Builder.of(twillRuntimeSpec.getZkConnectStr()).build(),
          RetryStrategies.fixDelay(1, TimeUnit.SECONDS)
        )
      ), "/" + twillRuntimeSpec.getTwillAppName()
    )
  );
}
 

private ZKClientService getZKClientService(String zkConnect) {
  return ZKClientServices.delegate(
    ZKClients.reWatchOnExpire(
      ZKClients.retryOnFailure(ZKClientService.Builder.of(zkConnect)
                                 .setSessionTimeout(ZK_TIMEOUT)
                                 .build(), RetryStrategies.exponentialDelay(100, 2000, TimeUnit.MILLISECONDS))));
}
 

@Override
public void start() {
  Preconditions.checkNotNull(zkConnectStr);

  eventConverter = new LogEventConverter(hostname, runnableName);
  scheduler = Executors.newSingleThreadScheduledExecutor(Threads.createDaemonThreadFactory(PUBLISH_THREAD_NAME));

  zkClientService = ZKClientServices.delegate(
    ZKClients.reWatchOnExpire(
      ZKClients.retryOnFailure(ZKClientService.Builder.of(zkConnectStr).build(),
                               RetryStrategies.fixDelay(1, TimeUnit.SECONDS))));

  kafkaClient = new ZKKafkaClientService(zkClientService);
  Futures.addCallback(Services.chainStart(zkClientService, kafkaClient),
                      new FutureCallback<List<ListenableFuture<Service.State>>>() {
    @Override
    public void onSuccess(List<ListenableFuture<Service.State>> result) {
      for (ListenableFuture<Service.State> future : result) {
        Preconditions.checkState(Futures.getUnchecked(future) == Service.State.RUNNING,
                                 "Service is not running.");
      }
      addInfo("Kafka client started: " + zkConnectStr);
      scheduler.scheduleWithFixedDelay(flushTask, 0, flushPeriod, TimeUnit.MILLISECONDS);
    }

    @Override
    public void onFailure(Throwable t) {
      // Fail to talk to kafka. Other than logging, what can be done?
      addError("Failed to start kafka appender.", t);
    }
  }, Threads.SAME_THREAD_EXECUTOR);

  super.start();
}
 

@Test (timeout = 30000)
public void testDoubleRegister() throws Exception {
  Map.Entry<DiscoveryService, DiscoveryServiceClient> entry = create();
  try {
    DiscoveryService discoveryService = entry.getKey();
    DiscoveryServiceClient discoveryServiceClient = entry.getValue();

    // Register on the same host port, it shouldn't fail.
    Cancellable cancellable = register(discoveryService, "test_double_reg", "localhost", 54321);
    Cancellable cancellable2 = register(discoveryService, "test_double_reg", "localhost", 54321);

    ServiceDiscovered discoverables = discoveryServiceClient.discover("test_double_reg");

    Assert.assertTrue(waitTillExpected(1, discoverables));

    cancellable.cancel();
    cancellable2.cancel();

    // Register again with two different clients, but killing session of the first one.
    final ZKClientService zkClient2 = ZKClientServices.delegate(
      ZKClients.retryOnFailure(
        ZKClients.reWatchOnExpire(
          ZKClientService.Builder.of(zkServer.getConnectionStr()).build()),
        RetryStrategies.fixDelay(1, TimeUnit.SECONDS)));
    zkClient2.startAndWait();

    try (ZKDiscoveryService discoveryService2 = new ZKDiscoveryService(zkClient2)) {
      cancellable2 = register(discoveryService2, "test_multi_client", "localhost", 54321);

      // Schedule a thread to shutdown zkClient2.
      new Thread() {
        @Override
        public void run() {
          try {
            TimeUnit.SECONDS.sleep(2);
            zkClient2.stopAndWait();
          } catch (InterruptedException e) {
            LOG.error(e.getMessage(), e);
          }
        }
      }.start();

      // This call would block until zkClient2 is shutdown.
      cancellable = register(discoveryService, "test_multi_client", "localhost", 54321);
      cancellable.cancel();
    } finally {
      zkClient2.stopAndWait();
    }
  } finally {
    closeServices(entry);
  }
}