public void addChildWatcher(String path) throws Exception {
   // path=/webServiceCenter/userCenter/tc.dd.test.do
   // 对path下的子节点进行监控,即就是对ip监控
   final PathChildrenCache cache = new PathChildrenCache(this.client, path, true);
   cache.start(StartMode.POST_INITIALIZED_EVENT); // ppt中需要讲StartMode
   // System.out.println(cache.getCurrentData().size());
   cache
       .getListenable()
       .addListener(
           new PathChildrenCacheListener() {
             public void childEvent(CuratorFramework client, PathChildrenCacheEvent event)
                 throws Exception {
               if (event.getType().equals(PathChildrenCacheEvent.Type.INITIALIZED)) {
                 System.out.println("客户端子节点cache初始化数据完成");
                 // System.out.println("size="+cache.getCurrentData().size());
               } else if (event.getType().equals(PathChildrenCacheEvent.Type.CHILD_ADDED)) {
                 // System.out.println("添加子节点:"+event.getData().getPath());
                 // System.out.println("修改子节点数据:"+new String(event.getData().getData()));
                 updateLocalService(event.getData().getPath(), 0);
               } else if (event.getType().equals(PathChildrenCacheEvent.Type.CHILD_REMOVED)) {
                 System.out.println("删除子节点:" + event.getData().getPath());
                 // if(services.containsKey(event.getData().getPath()))
                 // servicesByP.containsKey(event.getData().)
                 updateLocalService(event.getData().getPath(), 1);
               } else if (event.getType().equals(PathChildrenCacheEvent.Type.CHILD_UPDATED)) {
                 // System.out.println("修改子节点数据:"+event.getData().getPath());
                 // System.out.println("修改子节点数据:"+new String(event.getData().getData()));
               }
             }
           });
 }
  public static void main(String[] args) throws Exception {
    CuratorFramework client = null;
    PathChildrenCache cache = null;
    try {
      client =
          CuratorFrameworkFactory.newClient("localhost:2181", new ExponentialBackoffRetry(1000, 3));
      client.start();

      // in this example we will cache data. Notice that this is optional.
      cache = new PathChildrenCache(client, PATH, true);
      cache.start();

      processCommands(client, cache);
    } finally {
      Closeables.closeQuietly(cache);
      Closeables.closeQuietly(client);
    }
  }
  /**
   * 监听某个节点下的直接一级节点 孩子节点的创建,删除,更新
   *
   * @throws Exception
   */
  @Test
  public void testWatcherPath() throws Exception {
    // 2.Register watcher
    PathChildrenCache watcher =
        new PathChildrenCache(
            client, ZK_PATH, true // if cache data
            );

    watcher
        .getListenable()
        .addListener(
            new PathChildrenCacheListener() {
              @Override
              public void childEvent(CuratorFramework client, PathChildrenCacheEvent event)
                  throws Exception {
                ChildData data = event.getData();
                if (data == null) {
                  System.out.println("No data in event[" + event + "]");
                } else {
                  System.out.println(
                      "Receive event: "
                          + "type=["
                          + event.getType()
                          + "]"
                          + ", path=["
                          + data.getPath()
                          + "]"
                          + ", data=["
                          + new String(data.getData())
                          + "]"
                          + ", stat=["
                          + data.getStat()
                          + "]");
                }
              }
            });

    watcher.start(PathChildrenCache.StartMode.BUILD_INITIAL_CACHE);
    System.out.println("Register zk watcher successfully!");

    Thread.sleep(Integer.MAX_VALUE);
  }
  @LifecycleStart
  public void start() throws IOException {
    synchronized (lock) {
      if (started) {
        return;
      }

      log.info("Starting zkCoordinator for server[%s]", me.getName());

      final String loadQueueLocation = ZKPaths.makePath(zkPaths.getLoadQueuePath(), me.getName());
      final String servedSegmentsLocation =
          ZKPaths.makePath(zkPaths.getServedSegmentsPath(), me.getName());
      final String liveSegmentsLocation =
          ZKPaths.makePath(zkPaths.getLiveSegmentsPath(), me.getName());

      loadQueueCache = new PathChildrenCache(curator, loadQueueLocation, true, true, loadingExec);

      try {
        curator.newNamespaceAwareEnsurePath(loadQueueLocation).ensure(curator.getZookeeperClient());
        curator
            .newNamespaceAwareEnsurePath(servedSegmentsLocation)
            .ensure(curator.getZookeeperClient());
        curator
            .newNamespaceAwareEnsurePath(liveSegmentsLocation)
            .ensure(curator.getZookeeperClient());

        loadLocalCache();

        loadQueueCache
            .getListenable()
            .addListener(
                new PathChildrenCacheListener() {
                  @Override
                  public void childEvent(CuratorFramework client, PathChildrenCacheEvent event)
                      throws Exception {
                    final ChildData child = event.getData();
                    switch (event.getType()) {
                      case CHILD_ADDED:
                        final String path = child.getPath();
                        final DataSegmentChangeRequest request =
                            jsonMapper.readValue(child.getData(), DataSegmentChangeRequest.class);

                        log.info("New request[%s] with zNode[%s].", request.asString(), path);

                        try {
                          request.go(
                              getDataSegmentChangeHandler(),
                              new DataSegmentChangeCallback() {
                                boolean hasRun = false;

                                @Override
                                public void execute() {
                                  try {
                                    if (!hasRun) {
                                      curator.delete().guaranteed().forPath(path);
                                      log.info("Completed request [%s]", request.asString());
                                      hasRun = true;
                                    }
                                  } catch (Exception e) {
                                    try {
                                      curator.delete().guaranteed().forPath(path);
                                    } catch (Exception e1) {
                                      log.error(
                                          e1,
                                          "Failed to delete zNode[%s], but ignoring exception.",
                                          path);
                                    }
                                    log.error(e, "Exception while removing zNode[%s]", path);
                                    throw Throwables.propagate(e);
                                  }
                                }
                              });
                        } catch (Exception e) {
                          try {
                            curator.delete().guaranteed().forPath(path);
                          } catch (Exception e1) {
                            log.error(
                                e1, "Failed to delete zNode[%s], but ignoring exception.", path);
                          }

                          log.makeAlert(e, "Segment load/unload: uncaught exception.")
                              .addData("node", path)
                              .addData("nodeProperties", request)
                              .emit();
                        }

                        break;
                      case CHILD_REMOVED:
                        log.info("zNode[%s] was removed", event.getData().getPath());
                        break;
                      default:
                        log.info("Ignoring event[%s]", event);
                    }
                  }
                });
        loadQueueCache.start();
      } catch (Exception e) {
        Throwables.propagateIfPossible(e, IOException.class);
        throw Throwables.propagate(e);
      }

      started = true;
    }
  }
示例#5
0
  @LifecycleStart
  public void start() throws IOException {
    log.info("Starting zkCoordinator for server[%s]", me);
    synchronized (lock) {
      if (started) {
        return;
      }

      final String loadQueueLocation = ZKPaths.makePath(zkPaths.getLoadQueuePath(), me.getName());
      final String servedSegmentsLocation =
          ZKPaths.makePath(zkPaths.getServedSegmentsPath(), me.getName());
      final String liveSegmentsLocation =
          ZKPaths.makePath(zkPaths.getLiveSegmentsPath(), me.getName());

      loadQueueCache =
          new PathChildrenCache(
              curator,
              loadQueueLocation,
              true,
              true,
              new ThreadFactoryBuilder().setDaemon(true).setNameFormat("ZkCoordinator-%s").build());

      try {
        config.getInfoDir().mkdirs();

        curator.newNamespaceAwareEnsurePath(loadQueueLocation).ensure(curator.getZookeeperClient());
        curator
            .newNamespaceAwareEnsurePath(servedSegmentsLocation)
            .ensure(curator.getZookeeperClient());
        curator
            .newNamespaceAwareEnsurePath(liveSegmentsLocation)
            .ensure(curator.getZookeeperClient());

        loadCache();

        loadQueueCache
            .getListenable()
            .addListener(
                new PathChildrenCacheListener() {
                  @Override
                  public void childEvent(CuratorFramework client, PathChildrenCacheEvent event)
                      throws Exception {
                    final ChildData child = event.getData();
                    switch (event.getType()) {
                      case CHILD_ADDED:
                        final String path = child.getPath();
                        final DataSegmentChangeRequest segment =
                            jsonMapper.readValue(child.getData(), DataSegmentChangeRequest.class);

                        log.info("New node[%s] with segmentClass[%s]", path, segment.getClass());

                        try {
                          segment.go(ZkCoordinator.this);
                          curator.delete().guaranteed().forPath(path);

                          log.info("Completed processing for node[%s]", path);
                        } catch (Exception e) {
                          try {
                            curator.delete().guaranteed().forPath(path);
                          } catch (Exception e1) {
                            log.info(
                                e1, "Failed to delete node[%s], but ignoring exception.", path);
                          }

                          log.makeAlert(e, "Segment load/unload: uncaught exception.")
                              .addData("node", path)
                              .addData("nodeProperties", segment)
                              .emit();
                        }

                        break;
                      case CHILD_REMOVED:
                        log.info("%s was removed", event.getData().getPath());
                        break;
                      default:
                        log.info("Ignoring event[%s]", event);
                    }
                  }
                });
        loadQueueCache.start();
      } catch (Exception e) {
        Throwables.propagateIfPossible(e, IOException.class);
        throw Throwables.propagate(e);
      }

      started = true;
    }
  }