Examples with LiveInstanceChangeListener org.apache.helix.LiveInstanceChangeListener used on opensource projects

Example 1 with LiveInstanceChangeListener

use of org.apache.helix.LiveInstanceChangeListener in project helix by apache.

the class TestZKLiveInstanceData method testDataChange.

@Test
public void testDataChange() throws Exception {
    // Create an admin and add LiveInstanceChange listener to it
    HelixManager adminManager = HelixManagerFactory.getZKHelixManager(clusterName, null, InstanceType.ADMINISTRATOR, ZK_ADDR);
    adminManager.connect();
    final BlockingQueue<List<LiveInstance>> changeList = new LinkedBlockingQueue<List<LiveInstance>>();
    adminManager.addLiveInstanceChangeListener(new LiveInstanceChangeListener() {

        @Override
        public void onLiveInstanceChange(List<LiveInstance> liveInstances, NotificationContext changeContext) {
            // The queue is basically unbounded, so shouldn't throw exception when calling
            // "add".
            changeList.add(deepCopy(liveInstances));
        }
    });
    // Check the initial condition
    List<LiveInstance> instances = changeList.poll(1, TimeUnit.SECONDS);
    Assert.assertNotNull(instances, "Expecting a list of live instance");
    Assert.assertTrue(instances.isEmpty(), "Expecting an empty list of live instance");
    // Join as participant, should trigger a live instance change event
    HelixManager manager = HelixManagerFactory.getZKHelixManager(clusterName, "localhost_54321", InstanceType.PARTICIPANT, ZK_ADDR);
    manager.connect();
    instances = changeList.poll(1, TimeUnit.SECONDS);
    Assert.assertNotNull(instances, "Expecting a list of live instance");
    Assert.assertEquals(instances.size(), 1, "Expecting one live instance");
    Assert.assertEquals(instances.get(0).getInstanceName(), manager.getInstanceName());
    // Update data in the live instance node, should trigger another live instance change
    // event
    HelixDataAccessor helixDataAccessor = manager.getHelixDataAccessor();
    PropertyKey propertyKey = helixDataAccessor.keyBuilder().liveInstance(manager.getInstanceName());
    LiveInstance instance = helixDataAccessor.getProperty(propertyKey);
    Map<String, String> map = new TreeMap<String, String>();
    map.put("k1", "v1");
    instance.getRecord().setMapField("test", map);
    Assert.assertTrue(helixDataAccessor.updateProperty(propertyKey, instance), "Failed to update live instance node");
    instances = changeList.poll(1, TimeUnit.SECONDS);
    Assert.assertNotNull(instances, "Expecting a list of live instance");
    Assert.assertEquals(instances.get(0).getRecord().getMapField("test"), map, "Wrong map data.");
    manager.disconnect();
    // wait for callback finish
    Thread.sleep(1000);
    instances = changeList.poll(1, TimeUnit.SECONDS);
    Assert.assertNotNull(instances, "Expecting a list of live instance");
    Assert.assertTrue(instances.isEmpty(), "Expecting an empty list of live instance");
    adminManager.disconnect();
}

Example 2 with LiveInstanceChangeListener

use of org.apache.helix.LiveInstanceChangeListener in project helix by apache.

the class ServiceDiscovery method setupWatcher.

private void setupWatcher() throws Exception {
    LiveInstanceChangeListener listener = new LiveInstanceChangeListener() {

        @Override
        public void onLiveInstanceChange(List<LiveInstance> liveInstances, NotificationContext changeContext) {
            if (changeContext.getType() != NotificationContext.Type.FINALIZE) {
                refreshCache();
            }
        }
    };
    admin.addLiveInstanceChangeListener(listener);
}