@Override
    public IdealState computeNewIdealState(
        String resourceName,
        IdealState currentIdealState,
        CurrentStateOutput currentStateOutput,
        ClusterDataCache clusterData) {
      testRebalancerInvoked = true;
      for (String partition : currentIdealState.getPartitionSet()) {
        String instance = currentIdealState.getPreferenceList(partition).get(0);
        currentIdealState.getPreferenceList(partition).clear();
        currentIdealState.getPreferenceList(partition).add(instance);

        currentIdealState.getInstanceStateMap(partition).clear();
        currentIdealState.getInstanceStateMap(partition).put(instance, "MASTER");
      }
      currentIdealState.setReplicas("1");
      return currentIdealState;
    }
  @Test
  public void testCustomizedIdealStateRebalancer() throws InterruptedException {
    _setupTool.addResourceToCluster(CLUSTER_NAME, db2, 60, "MasterSlave");
    _setupTool.addResourceProperty(
        CLUSTER_NAME,
        db2,
        IdealStateProperty.REBALANCER_CLASS_NAME.toString(),
        TestCustomizedIdealStateRebalancer.TestRebalancer.class.getName());
    _setupTool.addResourceProperty(
        CLUSTER_NAME,
        db2,
        IdealStateProperty.REBALANCE_MODE.toString(),
        RebalanceMode.USER_DEFINED.toString());

    _setupTool.rebalanceStorageCluster(CLUSTER_NAME, db2, 3);

    boolean result =
        ClusterStateVerifier.verifyByZkCallback(
            new ExternalViewBalancedVerifier(_gZkClient, CLUSTER_NAME, db2));
    Assert.assertTrue(result);
    Thread.sleep(1000);
    HelixDataAccessor accessor =
        new ZKHelixDataAccessor(CLUSTER_NAME, new ZkBaseDataAccessor<ZNRecord>(_gZkClient));
    Builder keyBuilder = accessor.keyBuilder();
    ExternalView ev = accessor.getProperty(keyBuilder.externalView(db2));
    Assert.assertEquals(ev.getPartitionSet().size(), 60);
    for (String partition : ev.getPartitionSet()) {
      Assert.assertEquals(ev.getStateMap(partition).size(), 1);
    }
    IdealState is = accessor.getProperty(keyBuilder.idealStates(db2));
    for (String partition : is.getPartitionSet()) {
      Assert.assertEquals(is.getPreferenceList(partition).size(), 3);
      Assert.assertEquals(is.getInstanceStateMap(partition).size(), 3);
    }
    Assert.assertTrue(testRebalancerCreated);
    Assert.assertTrue(testRebalancerInvoked);
  }
Ejemplo n.º 3
0
  @Override
  public void onCallback(NotificationContext context) {
    LOG.info(
        "START: MasterSlaveRebalancer.onCallback running at "
            + _context.getHelixManager().getInstanceName());

    if (context.getType().equals(NotificationContext.Type.FINALIZE)) {
      LOG.info(
          "END: MasterSlaveRebalancer.onCallback FINALIZE callback invoked. Likely lost connection to Helix");
      return;
    }

    HelixManager manager = context.getManager();
    String clusterName = manager.getClusterName();
    HelixAdmin helixAdmin = manager.getClusterManagmentTool();
    IdealState idealState =
        helixAdmin.getResourceIdealState(clusterName, MySQLConstants.MASTER_SLAVE_RESOURCE_NAME);

    if (idealState == null) {
      LOG.info(
          "END: MasterSlaveRebalancer.onCallback. "
              + MySQLConstants.MASTER_SLAVE_RESOURCE_NAME
              + " is not yet created");
    }

    PropertyKey.Builder builder = new PropertyKey.Builder(clusterName);
    Map<String, LiveInstance> liveInstancesMap =
        manager.getHelixDataAccessor().getChildValuesMap(builder.liveInstances());

    Map<String, InstanceConfig> instanceConfigs =
        manager.getHelixDataAccessor().getChildValuesMap(builder.instanceConfigs());

    IdealState newIdealState = new IdealState(idealState.getId());
    newIdealState.getRecord().setSimpleFields(idealState.getRecord().getSimpleFields());
    newIdealState.getRecord().setListFields(idealState.getRecord().getListFields());
    for (String partition : idealState.getPartitionSet()) {
      Map<String, String> instanceStateMap = idealState.getInstanceStateMap(partition);
      String currMaster = null;
      Set<String> slaveSet = new TreeSet<String>();
      for (String instance : instanceStateMap.keySet()) {
        if ("MASTER".equalsIgnoreCase(instanceStateMap.get(instance))) {
          currMaster = instance;
        }
        if ("SLAVE".equalsIgnoreCase(instanceStateMap.get(instance))) {
          slaveSet.add(instance);
        }
      }
      String newMaster = currMaster;
      if (!liveInstancesMap.containsKey(currMaster)
          || !instanceConfigs.get(currMaster).getInstanceEnabled()) {
        // need to find a new master.
        newMaster = findNewMaster(liveInstancesMap, instanceConfigs, currMaster, slaveSet);
      }
      for (String instance : instanceStateMap.keySet()) {
        if (instance.equalsIgnoreCase(newMaster)) {
          newIdealState.setPartitionState(partition, instance, "MASTER");
        } else {
          newIdealState.setPartitionState(partition, instance, "SLAVE");
        }
      }
    }
    if (!idealState.equals(newIdealState)) {
      LOG.info("New idealstate computed.");
      LOG.info(newIdealState.toString());
      manager
          .getClusterManagmentTool()
          .setResourceIdealState(
              clusterName, MySQLConstants.MASTER_SLAVE_RESOURCE_NAME, newIdealState);
    } else {
      LOG.info("No change in IdealState");
    }
    LOG.info("END: MasterSlaveRebalancer.onCallback");
  }