Java Code Examples for com.datatorrent.stram.plan.logical.LogicalPlan#getMeta()

@Test
public void testGenericOperatorPropertyCodec()
{
  LogicalPlan dag = new LogicalPlan();
  Map<Class<?>, Class<? extends StringCodec<?>>> codecs = new HashMap<>();
  codecs.put(GenericOperatorProperty.class, GenericOperatorProperty.GenericOperatorPropertyStringCodec.class);
  dag.setAttribute(com.datatorrent.api.Context.DAGContext.STRING_CODECS, codecs);
  dag.setAttribute(com.datatorrent.api.Context.OperatorContext.STORAGE_AGENT, new MemoryStorageAgent());

  GenericTestOperator o1 = dag.addOperator("o1", GenericTestOperator.class);
  OperatorMeta o1Meta = dag.getMeta(o1);

  TestPlanContext ctx = new TestPlanContext();
  PhysicalPlan plan = new PhysicalPlan(dag, ctx);
  ctx.deploy.clear();
  ctx.undeploy.clear();

  PlanModifier pm = new PlanModifier(plan);
  try {
    pm.setOperatorProperty(o1Meta.getName(), "genericOperatorProperty", "xyz");
    Assert.fail("validation error expected"); // cannot set properties on an operator that is already deployed.
  } catch (javax.validation.ValidationException e) {
    Assert.assertTrue(e.getMessage().contains(o1Meta.toString()));
  }

  GenericTestOperator newOperator = new GenericTestOperator();
  pm.addOperator("newOperator", newOperator);
  pm.setOperatorProperty("newOperator", "genericOperatorProperty", "xyz");
  Assert.assertEquals("", "xyz", newOperator.getGenericOperatorProperty().obtainString());
}
 

@Test
public void testStaticPartitioning()
{
  LogicalPlan dag = new LogicalPlan();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, new StramTestSupport.MemoryStorageAgent());

  TestGeneratorInputOperator node0 = dag.addOperator("node0", TestGeneratorInputOperator.class);
  GenericTestOperator node1 = dag.addOperator("node1", GenericTestOperator.class);
  PartitioningTestOperator partitioned = dag.addOperator("partitioned", PartitioningTestOperator.class);
  partitioned.setPartitionCount(partitioned.partitionKeys.length);
  GenericTestOperator singleton1 = dag.addOperator("singleton1", GenericTestOperator.class);
  GenericTestOperator singleton2 = dag.addOperator("singleton2", GenericTestOperator.class);

  dag.addStream("n0.inport1", node0.outport, node1.inport1);
  dag.addStream("n1.outport1", node1.outport1, partitioned.inport1, partitioned.inportWithCodec);
  dag.addStream("mergeStream", partitioned.outport1, singleton1.inport1, singleton2.inport1);

  dag.setAttribute(LogicalPlan.CONTAINERS_MAX_COUNT, 2);

  OperatorMeta partitionedMeta = dag.getMeta(partitioned);

  dag.validate();

  PhysicalPlan plan = new PhysicalPlan(dag, new TestPlanContext());

  Assert.assertEquals("number of containers", 2, plan.getContainers().size());
  Assert.assertNotNull("partition map", partitioned.partitions);
  Assert.assertEquals("partition map " + partitioned.partitions, 3, partitioned.partitions.size());

  List<PTOperator> n2Instances = plan.getOperators(partitionedMeta);
  Assert.assertEquals("partition instances " + n2Instances, partitioned.partitionKeys.length, n2Instances.size());
  for (int i = 0; i < n2Instances.size(); i++) {
    PTOperator po = n2Instances.get(i);
    Map<String, PTInput> inputsMap = new HashMap<>();
    for (PTInput input: po.getInputs()) {
      inputsMap.put(input.portName, input);
      Assert.assertEquals("partitions " + input, Sets.newHashSet(partitioned.partitionKeys[i]), input.partitions.partitions);
      //Assert.assertEquals("codec " + input.logicalStream, PartitioningTestStreamCodec.class, input.logicalStream.getCodecClass());
    }
    Assert.assertEquals("number inputs " + inputsMap, Sets.newHashSet(PartitioningTestOperator.IPORT1, PartitioningTestOperator.INPORT_WITH_CODEC), inputsMap.keySet());
  }

  Collection<PTOperator> unifiers = plan.getMergeOperators(partitionedMeta);
  Assert.assertEquals("number unifiers " + partitionedMeta, 0, unifiers.size());
}
 

@Test
public void testDefaultPartitioning()
{
  LogicalPlan dag = new LogicalPlan();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, new StramTestSupport.MemoryStorageAgent());

  GenericTestOperator node1 = dag.addOperator("node1", GenericTestOperator.class);
  GenericTestOperator node2 = dag.addOperator("node2", GenericTestOperator.class);
  dag.addStream("node1.outport1", node1.outport1, node2.inport2, node2.inport1);

  int initialPartitionCount = 5;
  OperatorMeta node2Decl = dag.getMeta(node2);
  node2Decl.getAttributes().put(OperatorContext.PARTITIONER, new StatelessPartitioner<GenericTestOperator>(initialPartitionCount));

  PhysicalPlan plan = new PhysicalPlan(dag, new TestPlanContext());

  List<PTOperator> n2Instances = plan.getOperators(node2Decl);
  Assert.assertEquals("partition instances " + n2Instances, initialPartitionCount, n2Instances.size());

  List<Integer> assignedPartitionKeys = Lists.newArrayList();

  for (int i = 0; i < n2Instances.size(); i++) {
    PTOperator n2Partition = n2Instances.get(i);
    Assert.assertNotNull("partition keys null: " + n2Partition, n2Partition.getPartitionKeys());
    Map<InputPort<?>, PartitionKeys> pkeys = n2Partition.getPartitionKeys();
    Assert.assertEquals("partition keys size: " + pkeys, 1, pkeys.size()); // one port partitioned
    InputPort<?> expectedPort = node2.inport2;
    Assert.assertEquals("partition port: " + pkeys, expectedPort, pkeys.keySet().iterator().next());

    Assert.assertEquals("partition mask: " + pkeys, "111", Integer.toBinaryString(pkeys.get(expectedPort).mask));
    Set<Integer> pks = pkeys.get(expectedPort).partitions;
    Assert.assertTrue("number partition keys: " + pkeys, pks.size() == 1 || pks.size() == 2);
    assignedPartitionKeys.addAll(pks);
  }

  int expectedMask = Integer.parseInt("111", 2);
  Assert.assertEquals("assigned partitions ", expectedMask + 1, assignedPartitionKeys.size());
  for (int i = 0; i <= expectedMask; i++) {
    Assert.assertTrue("" + assignedPartitionKeys, assignedPartitionKeys.contains(i));
  }

}
 

@Test
public void testRepartitioningScaleUp()
{
  LogicalPlan dag = new LogicalPlan();

  GenericTestOperator o1 = dag.addOperator("o1", GenericTestOperator.class);
  GenericTestOperator o2 = dag.addOperator("o2", GenericTestOperator.class);
  GenericTestOperator mergeNode = dag.addOperator("mergeNode", GenericTestOperator.class);

  dag.addStream("o1.outport1", o1.outport1, o2.inport1, o2.inport2);
  dag.addStream("mergeStream", o2.outport1, mergeNode.inport1);

  OperatorMeta o2Meta = dag.getMeta(o2);
  o2Meta.getAttributes().put(OperatorContext.STATS_LISTENERS,
      Lists.newArrayList((StatsListener)new PartitionLoadWatch(0, 5)));
  o2Meta.getAttributes().put(OperatorContext.PARTITIONER, new StatelessPartitioner<GenericTestOperator>(1));

  TestPlanContext ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);
  PhysicalPlan plan = new PhysicalPlan(dag, ctx);

  Assert.assertEquals("number of operators", 3, plan.getAllOperators().size());
  Assert.assertEquals("number of save requests", 3, ctx.backupRequests);

  List<PTOperator> o2Partitions = plan.getOperators(o2Meta);
  Assert.assertEquals("partition count " + o2Meta, 1, o2Partitions.size());

  PTOperator o2p1 = o2Partitions.get(0);
  Assert.assertEquals("stats handlers " + o2p1, 1, o2p1.statsListeners.size());
  StatsListener sl = o2p1.statsListeners.get(0);
  Assert.assertTrue("stats handlers " + o2p1.statsListeners, sl instanceof PartitionLoadWatch);
  ((PartitionLoadWatch)sl).evalIntervalMillis = -1; // no delay

  setThroughput(o2p1, 10);
  plan.onStatusUpdate(o2p1);
  Assert.assertEquals("partitioning triggered", 1, ctx.events.size());
  ctx.backupRequests = 0;
  ctx.events.remove(0).run();

  o2Partitions = plan.getOperators(o2Meta);
  Assert.assertEquals("partition count " + o2Partitions, 2, o2Partitions.size());
  o2p1 = o2Partitions.get(0);
  Assert.assertEquals("sinks " + o2p1.getOutputs(), 1, o2p1.getOutputs().size());
  PTOperator o2p2 = o2Partitions.get(1);
  Assert.assertEquals("sinks " + o2p2.getOutputs(), 1, o2p2.getOutputs().size());

  Set<PTOperator> expUndeploy = Sets.newHashSet(plan.getOperators(dag.getMeta(mergeNode)));
  expUndeploy.add(o2p1);

  expUndeploy.addAll(plan.getOperators(dag.getMeta(mergeNode)).get(0).upstreamMerge.values());

  // verify load update generates expected events per configuration

  setThroughput(o2p1, 0);
  plan.onStatusUpdate(o2p1);
  Assert.assertEquals("load min", 0, ctx.events.size());

  setThroughput(o2p1, 3);
  plan.onStatusUpdate(o2p1);
  Assert.assertEquals("load within range", 0, ctx.events.size());

  setThroughput(o2p1, 10);
  plan.onStatusUpdate(o2p1);
  Assert.assertEquals("load exceeds max", 1, ctx.events.size());

  ctx.backupRequests = 0;
  ctx.events.remove(0).run();

  Assert.assertEquals("new partitions", 3, plan.getOperators(o2Meta).size());
  Assert.assertTrue("", plan.getOperators(o2Meta).contains(o2p2));

  for (PTOperator partition : plan.getOperators(o2Meta)) {
    Assert.assertNotNull("container null " + partition, partition.getContainer());
    Assert.assertEquals("outputs " + partition, 1, partition.getOutputs().size());
    Assert.assertEquals("downstream operators " + partition.getOutputs().get(0).sinks, 1, partition.getOutputs().get(0).sinks.size());
  }
  Assert.assertEquals("" + ctx.undeploy, expUndeploy, ctx.undeploy);

  Set<PTOperator> expDeploy = Sets.newHashSet(plan.getOperators(dag.getMeta(mergeNode)));
  expDeploy.addAll(plan.getOperators(o2Meta));
  expDeploy.remove(o2p2);

  expDeploy.addAll(plan.getOperators(dag.getMeta(mergeNode)).get(0).upstreamMerge.values());

  Assert.assertEquals("" + ctx.deploy, expDeploy, ctx.deploy);
  Assert.assertEquals("Count of storage requests", 2, ctx.backupRequests);

  // partitioning skipped on insufficient head room
  o2p1 = plan.getOperators(o2Meta).get(0);
  plan.setAvailableResources(0);
  setThroughput(o2p1, 10);
  plan.onStatusUpdate(o2p1);
  Assert.assertEquals("not repartitioned", 1, ctx.events.size());
  ctx.events.remove(0).run();
  Assert.assertEquals("partition count unchanged", 3, plan.getOperators(o2Meta).size());

}
 

/**
 * Test partitioning of an input operator (no input port).
 * Cover aspects that are not part of generic operator test.
 * Test scaling from one to multiple partitions with unifier when one partition remains unmodified.
 */
@Test
public void testInputOperatorPartitioning()
{
  LogicalPlan dag = new LogicalPlan();
  final TestInputOperator<Object> o1 = dag.addOperator("o1", new TestInputOperator<>());
  GenericTestOperator o2 = dag.addOperator("o2", GenericTestOperator.class);
  dag.addStream("o1.outport1", o1.output, o2.inport1);

  OperatorMeta o1Meta = dag.getMeta(o1);
  dag.setOperatorAttribute(o1, OperatorContext.STATS_LISTENERS, Arrays.asList(new StatsListener[]{new PartitioningTest.PartitionLoadWatch()}));
  TestPartitioner<TestInputOperator<Object>> partitioner = new TestPartitioner<>();
  dag.setOperatorAttribute(o1, OperatorContext.PARTITIONER, partitioner);

  TestPlanContext ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);
  PhysicalPlan plan = new PhysicalPlan(dag, ctx);
  Assert.assertEquals("number of containers", 2, plan.getContainers().size());

  List<PTOperator> o1Partitions = plan.getOperators(o1Meta);
  Assert.assertEquals("partitions " + o1Partitions, 1, o1Partitions.size());
  PTOperator o1p1 = o1Partitions.get(0);

  // verify load update generates expected events per configuration
  Assert.assertEquals("stats handlers " + o1p1, 1, o1p1.statsListeners.size());
  StatsListener l = o1p1.statsListeners.get(0);
  Assert.assertTrue("stats handlers " + o1p1.statsListeners, l instanceof PartitioningTest.PartitionLoadWatch);

  PartitioningTest.PartitionLoadWatch.put(o1p1, 1);
  plan.onStatusUpdate(o1p1);
  Assert.assertEquals("scale up triggered", 1, ctx.events.size());
  // add another partition, keep existing as is
  partitioner.extraPartitions.add(new DefaultPartition<>(o1));
  Runnable r = ctx.events.remove(0);
  r.run();
  partitioner.extraPartitions.clear();

  o1Partitions = plan.getOperators(o1Meta);
  Assert.assertEquals("operators after scale up", 2, o1Partitions.size());
  Assert.assertEquals("first partition unmodified", o1p1, o1Partitions.get(0));
  Assert.assertEquals("single output", 1, o1p1.getOutputs().size());
  Assert.assertEquals("output to unifier", 1, o1p1.getOutputs().get(0).sinks.size());

  Set<PTOperator> expUndeploy = Sets.newHashSet(plan.getOperators(dag.getMeta(o2)));
  Set<PTOperator> expDeploy = Sets.newHashSet(o1Partitions.get(1));
  expDeploy.addAll(plan.getMergeOperators(dag.getMeta(o1)));
  expDeploy.addAll(expUndeploy);
  expDeploy.add(o1p1.getOutputs().get(0).sinks.get(0).target);

  Assert.assertEquals("undeploy", expUndeploy, ctx.undeploy);
  Assert.assertEquals("deploy", expDeploy, ctx.deploy);

  for (PTOperator p : o1Partitions) {
    Assert.assertEquals("activation window id " + p, Checkpoint.INITIAL_CHECKPOINT, p.recoveryCheckpoint);
    Assert.assertEquals("checkpoints " + p + " " + p.checkpoints, Lists.newArrayList(), p.checkpoints);
    PartitioningTest.PartitionLoadWatch.put(p, -1);
    plan.onStatusUpdate(p);
  }
  ctx.events.remove(0).run();
  Assert.assertEquals("operators after scale down", 1, plan.getOperators(o1Meta).size());
}
 

/**
 * Test unifier gets removed when number partitions drops to 1.
 */
@Test
public void testRepartitioningScaleDownSinglePartition()
{
  LogicalPlan dag = new LogicalPlan();

  TestInputOperator<?> o1 = dag.addOperator("o1", TestInputOperator.class);
  GenericTestOperator o2 = dag.addOperator("o2", GenericTestOperator.class);

  dag.addStream("o1.outport1", o1.output, o2.inport1);
  OperatorMeta o1Meta = dag.getMeta(o1);
  dag.setOperatorAttribute(o1, OperatorContext.PARTITIONER, new StatelessPartitioner<GenericTestOperator>(2));
  dag.setOperatorAttribute(o1, OperatorContext.STATS_LISTENERS, Arrays.asList(new StatsListener[]{new PartitioningTest.PartitionLoadWatch()}));

  TestPlanContext ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);
  PhysicalPlan plan = new PhysicalPlan(dag, ctx);

  List<PTOperator> o1Partitions = plan.getOperators(o1Meta);
  Assert.assertEquals("partitions " + o1Partitions, 2, o1Partitions.size());
  PTOperator o1p1 = o1Partitions.get(0);
  PTOperator p1Doper = o1p1.getOutputs().get(0).sinks.get(0).target;
  Assert.assertSame("", p1Doper.getOperatorMeta(), o1Meta.getMeta(o1.output).getUnifierMeta());
  Assert.assertTrue("unifier ", p1Doper.isUnifier());
  Assert.assertEquals("Unifiers " + o1Meta, 1, o1p1.getOutputs().get(0).sinks.size());

  Collection<PTOperator> o1Unifiers = new ArrayList<>(plan.getOperators(dag.getMeta(o2)).get(0).upstreamMerge.values());

  StatsListener l = o1p1.statsListeners.get(0);
  Assert.assertTrue("stats handlers " + o1p1.statsListeners, l instanceof PartitioningTest.PartitionLoadWatch);
  PartitioningTest.PartitionLoadWatch.put(o1p1, -1);
  PartitioningTest.PartitionLoadWatch.put(o1Partitions.get(1), -1);

  plan.onStatusUpdate(o1p1);
  plan.onStatusUpdate(o1Partitions.get(1));
  Assert.assertEquals("partition scaling triggered", 1, ctx.events.size());
  ctx.events.remove(0).run();

  List<PTOperator> o1NewPartitions = plan.getOperators(o1Meta);
  Assert.assertEquals("partitions " + o1NewPartitions, 1, o1NewPartitions.size());

  List<PTOperator> o1NewUnifiers = new ArrayList<>(plan.getOperators(dag.getMeta(o2)).get(0).upstreamMerge.values());

  Assert.assertEquals("unifiers " + o1Meta, 0, o1NewUnifiers.size());
  p1Doper = o1p1.getOutputs().get(0).sinks.get(0).target;
  Assert.assertTrue("", p1Doper.getOperatorMeta() == dag.getMeta(o2));
  Assert.assertFalse("unifier ", p1Doper.isUnifier());

  Assert.assertTrue("removed unifier from deployment " + ctx.undeploy, ctx.undeploy.containsAll(o1Unifiers));
  Assert.assertFalse("removed unifier from deployment " + ctx.deploy, ctx.deploy.containsAll(o1Unifiers));

  // scale up, ensure unifier is setup at activation checkpoint
  setActivationCheckpoint(o1NewPartitions.get(0), 3);
  PartitioningTest.PartitionLoadWatch.put(o1NewPartitions.get(0), 1);
  plan.onStatusUpdate(o1NewPartitions.get(0));
  Assert.assertEquals("partition scaling triggered", 1, ctx.events.size());
  ctx.events.remove(0).run();

  o1NewUnifiers.addAll(plan.getOperators(dag.getMeta(o2)).get(0).upstreamMerge.values());

  Assert.assertEquals("unifiers " + o1Meta, 1, o1NewUnifiers.size());
  Assert.assertEquals("unifier activation checkpoint " + o1Meta, 3, o1NewUnifiers.get(0).recoveryCheckpoint.windowId);
}
 

@Test
@SuppressWarnings("unchecked")
public void testInline()
{

  LogicalPlan dag = new LogicalPlan();

  GenericTestOperator o1 = dag.addOperator("o1", GenericTestOperator.class);
  GenericTestOperator o2 = dag.addOperator("o2", GenericTestOperator.class);
  GenericTestOperator o3 = dag.addOperator("o3", GenericTestOperator.class);

  PartitioningTestOperator partOperator = dag.addOperator("partNode", PartitioningTestOperator.class);
  partOperator.partitionKeys = new Integer[] {0,1};
  dag.getMeta(partOperator).getAttributes().put(OperatorContext.PARTITIONER, new StatelessPartitioner<GenericTestOperator>(partOperator.partitionKeys.length));

  dag.addStream("o1_outport1", o1.outport1, o2.inport1, o3.inport1, partOperator.inport1)
          .setLocality(null);

  // same container for o2 and o3
  dag.addStream("o2_outport1", o2.outport1, o3.inport2)
      .setLocality(Locality.CONTAINER_LOCAL);

  dag.addStream("o3_outport1", o3.outport1, partOperator.inport2);

  int maxContainers = 4;
  dag.setAttribute(LogicalPlan.CONTAINERS_MAX_COUNT, maxContainers);
  dag.setAttribute(OperatorContext.STORAGE_AGENT, new TestPlanContext());

  PhysicalPlan plan = new PhysicalPlan(dag, new TestPlanContext());
  Assert.assertEquals("number of containers", maxContainers, plan.getContainers().size());
  Assert.assertEquals("operators container 0", 1, plan.getContainers().get(0).getOperators().size());

  Assert.assertEquals("operators container 0", 1, plan.getContainers().get(0).getOperators().size());
  Set<OperatorMeta> c2ExpNodes = Sets.newHashSet(dag.getMeta(o2), dag.getMeta(o3));
  Set<OperatorMeta> c2ActNodes = new HashSet<>();
  PTContainer c2 = plan.getContainers().get(1);
  for (PTOperator pNode : c2.getOperators()) {
    c2ActNodes.add(pNode.getOperatorMeta());
  }
  Assert.assertEquals("operators " + c2, c2ExpNodes, c2ActNodes);

  // one container per partition
  OperatorMeta partOperMeta = dag.getMeta(partOperator);
  List<PTOperator> partitions = plan.getOperators(partOperMeta);
  for (PTOperator partition : partitions) {
    Assert.assertEquals("operators container" + partition, 1, partition.getContainer().getOperators().size());
  }

}
 

/**
 * Test covering scenario when only new partitions are added during dynamic partitioning and there
 * are no changes to existing partitions and partition mapping
 */
@Test
public void testAugmentedDynamicPartitioning()
{
  LogicalPlan dag = new LogicalPlan();

  TestGeneratorInputOperator o1 = dag.addOperator("o1", TestGeneratorInputOperator.class);
  dag.setOperatorAttribute(o1, OperatorContext.PARTITIONER, new TestAugmentingPartitioner<TestGeneratorInputOperator>(3));
  dag.setOperatorAttribute(o1, OperatorContext.STATS_LISTENERS, Lists.newArrayList((StatsListener)new PartitioningTest.PartitionLoadWatch()));
  OperatorMeta o1Meta = dag.getMeta(o1);

  GenericTestOperator o2 = dag.addOperator("o2", GenericTestOperator.class);
  OperatorMeta o2Meta = dag.getMeta(o2);

  dag.addStream("o1.outport1", o1.outport, o2.inport1);

  int maxContainers = 10;
  dag.setAttribute(LogicalPlan.CONTAINERS_MAX_COUNT, maxContainers);

  TestPlanContext ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);

  PhysicalPlan plan = new PhysicalPlan(dag, ctx);
  Assert.assertEquals("number of containers", 4, plan.getContainers().size());

  List<PTOperator> o1ops = plan.getOperators(o1Meta);
  Assert.assertEquals("number of o1 operators", 3, o1ops.size());

  List<PTOperator> o2ops = plan.getOperators(o2Meta);
  Assert.assertEquals("number of o2 operators", 1, o2ops.size());
  Set<PTOperator> expUndeploy = Sets.newLinkedHashSet();
  expUndeploy.addAll(plan.getOperators(o2Meta));
  expUndeploy.add(plan.getOperators(o2Meta).get(0).upstreamMerge.values().iterator().next());

  for (int i = 0; i < 2; ++i) {
    PartitioningTest.PartitionLoadWatch.put(o1ops.get(i), 1);
    plan.onStatusUpdate(o1ops.get(i));
  }

  ctx.backupRequests = 0;
  ctx.events.remove(0).run();

  Assert.assertEquals("number of containers", 6, plan.getContainers().size());

  Assert.assertEquals("undeployed opertors", expUndeploy, ctx.undeploy);
}
 

@Test
public void testSingleFinalUnifierInputOverride()
{
  LogicalPlan dag = new LogicalPlan();

  GenericTestOperator o1 = dag.addOperator("o1", GenericTestOperator.class);
  dag.setOperatorAttribute(o1, OperatorContext.PARTITIONER, new StatelessPartitioner<GenericTestOperator>(3));
  OperatorMeta o1Meta = dag.getMeta(o1);

  GenericTestOperator o2 =  dag.addOperator("o2", GenericTestOperator.class);
  dag.setOperatorAttribute(o2, OperatorContext.PARTITIONER, new StatelessPartitioner<GenericTestOperator>(2));
  dag.setInputPortAttribute(o2.inport1, PortContext.UNIFIER_SINGLE_FINAL, true);
  OperatorMeta o2Meta = dag.getMeta(o2);

  dag.addStream("o1.outport1", o1.outport1, o2.inport1);

  dag.setAttribute(LogicalPlan.CONTAINERS_MAX_COUNT, 10);

  TestPlanContext ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);

  PhysicalPlan plan = new PhysicalPlan(dag, ctx);
  Assert.assertEquals("number of containers", 6, plan.getContainers().size());

  Assert.assertEquals("o1 merge unifiers", 1, plan.getMergeOperators(o1Meta).size());

  dag.setOutputPortAttribute(o1.outport1, PortContext.UNIFIER_SINGLE_FINAL, false);
  ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);
  plan = new PhysicalPlan(dag, ctx);
  Assert.assertEquals("number of containers", 6, plan.getContainers().size());

  Assert.assertEquals("o1 merge unifiers", 1, plan.getMergeOperators(o1Meta).size());

  dag.setOutputPortAttribute(o1.outport1, PortContext.UNIFIER_SINGLE_FINAL, true);
  dag.setInputPortAttribute(o2.inport1, PortContext.UNIFIER_SINGLE_FINAL, false);
  ctx = new TestPlanContext();
  dag.setAttribute(OperatorContext.STORAGE_AGENT, ctx);
  plan = new PhysicalPlan(dag, ctx);
  Assert.assertEquals("number of containers", 5, plan.getContainers().size());

  Set<String> expectedNames = Sets.newHashSet(o1Meta.getMeta(o1.outport1).getUnifierMeta().getName(), o2Meta.getName());
  for (int i = 3; i < 5; ++i) {
    PTContainer container = plan.getContainers().get(i);
    Assert.assertEquals("o2 container size", 2, container.getOperators().size());

    Set<String> names = Sets.newHashSet();
    for (PTOperator operator : container.getOperators()) {
      names.add(operator.getOperatorMeta().getName());
    }
    Assert.assertEquals("o2 container operators", expectedNames, names);
  }
}