Java Code Examples for org.apache.flink.streaming.api.operators.StreamSource#close()

/**
 * Test restoring from an legacy empty state, when no partitions could be found for topics.
 */
@Test
public void testRestoreFromEmptyStateNoPartitions() throws Exception {
	final DummyFlinkKafkaConsumer<String> consumerFunction =
			new DummyFlinkKafkaConsumer<>(
				Collections.singletonList("dummy-topic"),
				Collections.<KafkaTopicPartition>emptyList(),
				FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

	StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator = new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();

	// restore state from binary snapshot file
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kafka-consumer-migration-test-flink" + testMigrateVersion + "-empty-state-snapshot"));

	testHarness.open();

	// assert that no partitions were found and is empty
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets() != null);
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());

	// assert that no state was restored
	assertTrue(consumerFunction.getRestoredState().isEmpty());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

/**
 * Test restoring from a non-empty state taken using a previous Flink version, when some partitions could be
 * found for topics.
 */
@Test
public void testRestore() throws Exception {
	final List<KafkaTopicPartition> partitions = new ArrayList<>(PARTITION_STATE.keySet());

	final DummyFlinkKafkaConsumer<String> consumerFunction =
		new DummyFlinkKafkaConsumer<>(TOPICS, partitions, FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

	StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator =
			new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();

	// restore state from binary snapshot file
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kafka-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));

	testHarness.open();

	// assert that there are partitions and is identical to expected list
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets() != null);
	assertTrue(!consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());

	// on restore, subscribedPartitionsToStartOffsets should be identical to the restored state
	assertEquals(PARTITION_STATE, consumerFunction.getSubscribedPartitionsToStartOffsets());

	// assert that state is correctly restored from legacy checkpoint
	assertTrue(consumerFunction.getRestoredState() != null);
	assertEquals(PARTITION_STATE, consumerFunction.getRestoredState());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

/**
 * Test restoring from a non-empty state taken using a previous Flink version, when some partitions could be
 * found for topics.
 */
@Test
public void testRestore() throws Exception {
	final List<KafkaTopicPartition> partitions = new ArrayList<>(PARTITION_STATE.keySet());

	final DummyFlinkKafkaConsumer<String> consumerFunction =
		new DummyFlinkKafkaConsumer<>(TOPICS, partitions, FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

	StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator =
			new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();

	// restore state from binary snapshot file
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kafka-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));

	testHarness.open();

	// assert that there are partitions and is identical to expected list
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets() != null);
	assertTrue(!consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());

	// on restore, subscribedPartitionsToStartOffsets should be identical to the restored state
	assertEquals(PARTITION_STATE, consumerFunction.getSubscribedPartitionsToStartOffsets());

	// assert that state is correctly restored from legacy checkpoint
	assertTrue(consumerFunction.getRestoredState() != null);
	assertEquals(PARTITION_STATE, consumerFunction.getRestoredState());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

/**
 * Test restoring from an legacy empty state, when no partitions could be found for topics.
 */
@Test
public void testRestoreFromEmptyStateNoPartitions() throws Exception {
	final DummyFlinkKafkaConsumer<String> consumerFunction =
			new DummyFlinkKafkaConsumer<>(
				Collections.singletonList("dummy-topic"),
				Collections.<KafkaTopicPartition>emptyList(),
				FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

	StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator = new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();

	// restore state from binary snapshot file
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kafka-consumer-migration-test-flink" + testMigrateVersion + "-empty-state-snapshot"));

	testHarness.open();

	// assert that no partitions were found and is empty
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets() != null);
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());

	// assert that no state was restored
	assertTrue(consumerFunction.getRestoredState().isEmpty());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

/**
 * Test restoring from a non-empty state taken using a previous Flink version, when some partitions could be
 * found for topics.
 */
@Test
public void testRestore() throws Exception {
	final List<KafkaTopicPartition> partitions = new ArrayList<>(PARTITION_STATE.keySet());

	final DummyFlinkKafkaConsumer<String> consumerFunction =
		new DummyFlinkKafkaConsumer<>(TOPICS, partitions, FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

	StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator =
			new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();

	// restore state from binary snapshot file
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kafka-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));

	testHarness.open();

	// assert that there are partitions and is identical to expected list
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets() != null);
	assertTrue(!consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());

	// on restore, subscribedPartitionsToStartOffsets should be identical to the restored state
	assertEquals(PARTITION_STATE, consumerFunction.getSubscribedPartitionsToStartOffsets());

	// assert that state is correctly restored from legacy checkpoint
	assertTrue(consumerFunction.getRestoredState() != null);
	assertEquals(PARTITION_STATE, consumerFunction.getRestoredState());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestoreWithEmptyState() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator = new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-empty-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that no state was restored
	assertTrue(consumerFunction.getRestoredState().isEmpty());

	// although the restore state is empty, the fetcher should still have been registered the initial discovered shard;
	// furthermore, the discovered shard should be considered a newly created shard while the job wasn't running,
	// and therefore should be consumed from the earliest sequence number
	KinesisStreamShardState restoredShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredShardState.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredShardState.getStreamShardHandle().isClosed());
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredShardState.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestore() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator =
		new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that state is correctly restored
	assertNotEquals(null, consumerFunction.getRestoredState());
	assertEquals(1, consumerFunction.getRestoredState().size());
	assertEquals(TEST_STATE, removeEquivalenceWrappers(consumerFunction.getRestoredState()));
	assertEquals(1, fetcher.getSubscribedShardsState().size());
	assertEquals(TEST_SEQUENCE_NUMBER, fetcher.getSubscribedShardsState().get(0).getLastProcessedSequenceNum());

	KinesisStreamShardState restoredShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredShardState.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredShardState.getStreamShardHandle().isClosed());
	assertEquals(TEST_SEQUENCE_NUMBER, restoredShardState.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestoreWithReshardedStream() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		// setup the closed shard
		Shard closedShard = new Shard();
		closedShard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange closedSequenceNumberRange = new SequenceNumberRange();
		closedSequenceNumberRange.withStartingSequenceNumber("1");
		closedSequenceNumberRange.withEndingSequenceNumber("1087654321"); // this represents a closed shard
		closedShard.setSequenceNumberRange(closedSequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), closedShard));

		// setup the new shards
		Shard newSplitShard1 = new Shard();
		newSplitShard1.setShardId(KinesisShardIdGenerator.generateFromShardOrder(1));

		SequenceNumberRange newSequenceNumberRange1 = new SequenceNumberRange();
		newSequenceNumberRange1.withStartingSequenceNumber("1087654322");
		newSplitShard1.setSequenceNumberRange(newSequenceNumberRange1);

		newSplitShard1.setParentShardId(TEST_SHARD_ID);

		Shard newSplitShard2 = new Shard();
		newSplitShard2.setShardId(KinesisShardIdGenerator.generateFromShardOrder(2));

		SequenceNumberRange newSequenceNumberRange2 = new SequenceNumberRange();
		newSequenceNumberRange2.withStartingSequenceNumber("2087654322");
		newSplitShard2.setSequenceNumberRange(newSequenceNumberRange2);

		newSplitShard2.setParentShardId(TEST_SHARD_ID);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), newSplitShard1));
		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), newSplitShard2));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator =
		new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that state is correctly restored
	assertNotEquals(null, consumerFunction.getRestoredState());
	assertEquals(1, consumerFunction.getRestoredState().size());
	assertEquals(TEST_STATE, removeEquivalenceWrappers(consumerFunction.getRestoredState()));

	// assert that the fetcher is registered with all shards, including new shards
	assertEquals(3, fetcher.getSubscribedShardsState().size());

	KinesisStreamShardState restoredClosedShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredClosedShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredClosedShardState.getStreamShardHandle().getShard().getShardId());
	assertTrue(restoredClosedShardState.getStreamShardHandle().isClosed());
	assertEquals(TEST_SEQUENCE_NUMBER, restoredClosedShardState.getLastProcessedSequenceNum());

	KinesisStreamShardState restoredNewSplitShard1 = fetcher.getSubscribedShardsState().get(1);
	assertEquals(TEST_STREAM_NAME, restoredNewSplitShard1.getStreamShardHandle().getStreamName());
	assertEquals(KinesisShardIdGenerator.generateFromShardOrder(1), restoredNewSplitShard1.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredNewSplitShard1.getStreamShardHandle().isClosed());
	// new shards should be consumed from the beginning
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredNewSplitShard1.getLastProcessedSequenceNum());

	KinesisStreamShardState restoredNewSplitShard2 = fetcher.getSubscribedShardsState().get(2);
	assertEquals(TEST_STREAM_NAME, restoredNewSplitShard2.getStreamShardHandle().getStreamName());
	assertEquals(KinesisShardIdGenerator.generateFromShardOrder(2), restoredNewSplitShard2.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredNewSplitShard2.getStreamShardHandle().isClosed());
	// new shards should be consumed from the beginning
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredNewSplitShard2.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@SuppressWarnings("unchecked")
private void writeSnapshot(String path, HashMap<StreamShardMetadata, SequenceNumber> state) throws Exception {
	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		new Properties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		state,
		null);

	final DummyFlinkKinesisConsumer<String> consumer = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator = new StreamSource<>(consumer);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();
	testHarness.open();

	final AtomicReference<Throwable> error = new AtomicReference<>();

	// run the source asynchronously
	Thread runner = new Thread() {
		@Override
		public void run() {
			try {
				consumer.run(new TestSourceContext<>());
			} catch (Throwable t) {
				t.printStackTrace();
				error.set(t);
			}
		}
	};
	runner.start();

	fetcher.waitUntilRun();

	final OperatorSubtaskState snapshot;
	synchronized (testHarness.getCheckpointLock()) {
		snapshot = testHarness.snapshot(0L, 0L);
	}

	OperatorSnapshotUtil.writeStateHandle(snapshot, path);

	consumerOperator.close();
	runner.join();
}
 

private void writeSnapshot(String path, HashMap<KafkaTopicPartition, Long> state) throws Exception {

		final OneShotLatch latch = new OneShotLatch();
		final AbstractFetcher<String, ?> fetcher = mock(AbstractFetcher.class);

		doAnswer(new Answer<Void>() {
			@Override
			public Void answer(InvocationOnMock invocation) throws Throwable {
				latch.trigger();
				return null;
			}
		}).when(fetcher).runFetchLoop();

		when(fetcher.snapshotCurrentState()).thenReturn(state);

		final List<KafkaTopicPartition> partitions = new ArrayList<>(PARTITION_STATE.keySet());

		final DummyFlinkKafkaConsumer<String> consumerFunction =
			new DummyFlinkKafkaConsumer<>(fetcher, TOPICS, partitions, FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

		StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator =
				new StreamSource<>(consumerFunction);

		final AbstractStreamOperatorTestHarness<String> testHarness =
				new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

		testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

		testHarness.setup();
		testHarness.open();

		final Throwable[] error = new Throwable[1];

		// run the source asynchronously
		Thread runner = new Thread() {
			@Override
			public void run() {
				try {
					consumerFunction.run(new DummySourceContext() {
						@Override
						public void collect(String element) {

						}
					});
				}
				catch (Throwable t) {
					t.printStackTrace();
					error[0] = t;
				}
			}
		};
		runner.start();

		if (!latch.isTriggered()) {
			latch.await();
		}

		final OperatorSubtaskState snapshot;
		synchronized (testHarness.getCheckpointLock()) {
			snapshot = testHarness.snapshot(0L, 0L);
		}

		OperatorSnapshotUtil.writeStateHandle(snapshot, path);

		consumerOperator.close();
		runner.join();
	}
 

@Test
public void testRestoreWithEmptyState() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator = new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-empty-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that no state was restored
	assertTrue(consumerFunction.getRestoredState().isEmpty());

	// although the restore state is empty, the fetcher should still have been registered the initial discovered shard;
	// furthermore, the discovered shard should be considered a newly created shard while the job wasn't running,
	// and therefore should be consumed from the earliest sequence number
	KinesisStreamShardState restoredShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredShardState.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredShardState.getStreamShardHandle().isClosed());
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredShardState.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestoreWithReshardedStream() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		// setup the closed shard
		Shard closedShard = new Shard();
		closedShard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange closedSequenceNumberRange = new SequenceNumberRange();
		closedSequenceNumberRange.withStartingSequenceNumber("1");
		closedSequenceNumberRange.withEndingSequenceNumber("1087654321"); // this represents a closed shard
		closedShard.setSequenceNumberRange(closedSequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), closedShard));

		// setup the new shards
		Shard newSplitShard1 = new Shard();
		newSplitShard1.setShardId(KinesisShardIdGenerator.generateFromShardOrder(1));

		SequenceNumberRange newSequenceNumberRange1 = new SequenceNumberRange();
		newSequenceNumberRange1.withStartingSequenceNumber("1087654322");
		newSplitShard1.setSequenceNumberRange(newSequenceNumberRange1);

		newSplitShard1.setParentShardId(TEST_SHARD_ID);

		Shard newSplitShard2 = new Shard();
		newSplitShard2.setShardId(KinesisShardIdGenerator.generateFromShardOrder(2));

		SequenceNumberRange newSequenceNumberRange2 = new SequenceNumberRange();
		newSequenceNumberRange2.withStartingSequenceNumber("2087654322");
		newSplitShard2.setSequenceNumberRange(newSequenceNumberRange2);

		newSplitShard2.setParentShardId(TEST_SHARD_ID);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), newSplitShard1));
		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), newSplitShard2));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator =
		new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that state is correctly restored
	assertNotEquals(null, consumerFunction.getRestoredState());
	assertEquals(1, consumerFunction.getRestoredState().size());
	assertEquals(TEST_STATE, removeEquivalenceWrappers(consumerFunction.getRestoredState()));

	// assert that the fetcher is registered with all shards, including new shards
	assertEquals(3, fetcher.getSubscribedShardsState().size());

	KinesisStreamShardState restoredClosedShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredClosedShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredClosedShardState.getStreamShardHandle().getShard().getShardId());
	assertTrue(restoredClosedShardState.getStreamShardHandle().isClosed());
	assertEquals(TEST_SEQUENCE_NUMBER, restoredClosedShardState.getLastProcessedSequenceNum());

	KinesisStreamShardState restoredNewSplitShard1 = fetcher.getSubscribedShardsState().get(1);
	assertEquals(TEST_STREAM_NAME, restoredNewSplitShard1.getStreamShardHandle().getStreamName());
	assertEquals(KinesisShardIdGenerator.generateFromShardOrder(1), restoredNewSplitShard1.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredNewSplitShard1.getStreamShardHandle().isClosed());
	// new shards should be consumed from the beginning
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredNewSplitShard1.getLastProcessedSequenceNum());

	KinesisStreamShardState restoredNewSplitShard2 = fetcher.getSubscribedShardsState().get(2);
	assertEquals(TEST_STREAM_NAME, restoredNewSplitShard2.getStreamShardHandle().getStreamName());
	assertEquals(KinesisShardIdGenerator.generateFromShardOrder(2), restoredNewSplitShard2.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredNewSplitShard2.getStreamShardHandle().isClosed());
	// new shards should be consumed from the beginning
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredNewSplitShard2.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestoreWithEmptyState() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator = new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-empty-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that no state was restored
	assertTrue(consumerFunction.getRestoredState().isEmpty());

	// although the restore state is empty, the fetcher should still have been registered the initial discovered shard;
	// furthermore, the discovered shard should be considered a newly created shard while the job wasn't running,
	// and therefore should be consumed from the earliest sequence number
	KinesisStreamShardState restoredShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredShardState.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredShardState.getStreamShardHandle().isClosed());
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredShardState.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestore() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator =
		new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that state is correctly restored
	assertNotEquals(null, consumerFunction.getRestoredState());
	assertEquals(1, consumerFunction.getRestoredState().size());
	assertEquals(TEST_STATE, removeEquivalenceWrappers(consumerFunction.getRestoredState()));
	assertEquals(1, fetcher.getSubscribedShardsState().size());
	assertEquals(TEST_SEQUENCE_NUMBER, fetcher.getSubscribedShardsState().get(0).getLastProcessedSequenceNum());

	KinesisStreamShardState restoredShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredShardState.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredShardState.getStreamShardHandle().isClosed());
	assertEquals(TEST_SEQUENCE_NUMBER, restoredShardState.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@Test
public void testRestoreWithReshardedStream() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		// setup the closed shard
		Shard closedShard = new Shard();
		closedShard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange closedSequenceNumberRange = new SequenceNumberRange();
		closedSequenceNumberRange.withStartingSequenceNumber("1");
		closedSequenceNumberRange.withEndingSequenceNumber("1087654321"); // this represents a closed shard
		closedShard.setSequenceNumberRange(closedSequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), closedShard));

		// setup the new shards
		Shard newSplitShard1 = new Shard();
		newSplitShard1.setShardId(KinesisShardIdGenerator.generateFromShardOrder(1));

		SequenceNumberRange newSequenceNumberRange1 = new SequenceNumberRange();
		newSequenceNumberRange1.withStartingSequenceNumber("1087654322");
		newSplitShard1.setSequenceNumberRange(newSequenceNumberRange1);

		newSplitShard1.setParentShardId(TEST_SHARD_ID);

		Shard newSplitShard2 = new Shard();
		newSplitShard2.setShardId(KinesisShardIdGenerator.generateFromShardOrder(2));

		SequenceNumberRange newSequenceNumberRange2 = new SequenceNumberRange();
		newSequenceNumberRange2.withStartingSequenceNumber("2087654322");
		newSplitShard2.setSequenceNumberRange(newSequenceNumberRange2);

		newSplitShard2.setParentShardId(TEST_SHARD_ID);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), newSplitShard1));
		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), newSplitShard2));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator =
		new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that state is correctly restored
	assertNotEquals(null, consumerFunction.getRestoredState());
	assertEquals(1, consumerFunction.getRestoredState().size());
	assertEquals(TEST_STATE, removeEquivalenceWrappers(consumerFunction.getRestoredState()));

	// assert that the fetcher is registered with all shards, including new shards
	assertEquals(3, fetcher.getSubscribedShardsState().size());

	KinesisStreamShardState restoredClosedShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredClosedShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredClosedShardState.getStreamShardHandle().getShard().getShardId());
	assertTrue(restoredClosedShardState.getStreamShardHandle().isClosed());
	assertEquals(TEST_SEQUENCE_NUMBER, restoredClosedShardState.getLastProcessedSequenceNum());

	KinesisStreamShardState restoredNewSplitShard1 = fetcher.getSubscribedShardsState().get(1);
	assertEquals(TEST_STREAM_NAME, restoredNewSplitShard1.getStreamShardHandle().getStreamName());
	assertEquals(KinesisShardIdGenerator.generateFromShardOrder(1), restoredNewSplitShard1.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredNewSplitShard1.getStreamShardHandle().isClosed());
	// new shards should be consumed from the beginning
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredNewSplitShard1.getLastProcessedSequenceNum());

	KinesisStreamShardState restoredNewSplitShard2 = fetcher.getSubscribedShardsState().get(2);
	assertEquals(TEST_STREAM_NAME, restoredNewSplitShard2.getStreamShardHandle().getStreamName());
	assertEquals(KinesisShardIdGenerator.generateFromShardOrder(2), restoredNewSplitShard2.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredNewSplitShard2.getStreamShardHandle().isClosed());
	// new shards should be consumed from the beginning
	assertEquals(SentinelSequenceNumber.SENTINEL_EARLIEST_SEQUENCE_NUM.get(), restoredNewSplitShard2.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@SuppressWarnings("unchecked")
private void writeSnapshot(String path, HashMap<StreamShardMetadata, SequenceNumber> state) throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(state.size());
	for (StreamShardMetadata shardMetadata : state.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		state,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumer = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator = new StreamSource<>(consumer);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();
	testHarness.open();

	final AtomicReference<Throwable> error = new AtomicReference<>();

	// run the source asynchronously
	Thread runner = new Thread() {
		@Override
		public void run() {
			try {
				consumer.run(new TestSourceContext<>());
			} catch (Throwable t) {
				t.printStackTrace();
				error.set(t);
			}
		}
	};
	runner.start();

	fetcher.waitUntilRun();

	final OperatorSubtaskState snapshot;
	synchronized (testHarness.getCheckpointLock()) {
		snapshot = testHarness.snapshot(0L, 0L);
	}

	OperatorSnapshotUtil.writeStateHandle(snapshot, path);

	consumerOperator.close();
	runner.join();
}
 

@Test
public void testRestore() throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(TEST_STATE.size());
	for (StreamShardMetadata shardMetadata : TEST_STATE.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		null,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumerFunction = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator =
		new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
		new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setup();
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kinesis-consumer-migration-test-flink" + testMigrateVersion + "-snapshot"));
	testHarness.open();

	consumerFunction.run(new TestSourceContext<>());

	// assert that state is correctly restored
	assertNotEquals(null, consumerFunction.getRestoredState());
	assertEquals(1, consumerFunction.getRestoredState().size());
	assertEquals(TEST_STATE, removeEquivalenceWrappers(consumerFunction.getRestoredState()));
	assertEquals(1, fetcher.getSubscribedShardsState().size());
	assertEquals(TEST_SEQUENCE_NUMBER, fetcher.getSubscribedShardsState().get(0).getLastProcessedSequenceNum());

	KinesisStreamShardState restoredShardState = fetcher.getSubscribedShardsState().get(0);
	assertEquals(TEST_STREAM_NAME, restoredShardState.getStreamShardHandle().getStreamName());
	assertEquals(TEST_SHARD_ID, restoredShardState.getStreamShardHandle().getShard().getShardId());
	assertFalse(restoredShardState.getStreamShardHandle().isClosed());
	assertEquals(TEST_SEQUENCE_NUMBER, restoredShardState.getLastProcessedSequenceNum());

	consumerOperator.close();
	consumerOperator.cancel();
}
 

@SuppressWarnings("unchecked")
private void writeSnapshot(String path, HashMap<StreamShardMetadata, SequenceNumber> state) throws Exception {
	final List<StreamShardHandle> initialDiscoveryShards = new ArrayList<>(state.size());
	for (StreamShardMetadata shardMetadata : state.keySet()) {
		Shard shard = new Shard();
		shard.setShardId(shardMetadata.getShardId());

		SequenceNumberRange sequenceNumberRange = new SequenceNumberRange();
		sequenceNumberRange.withStartingSequenceNumber("1");
		shard.setSequenceNumberRange(sequenceNumberRange);

		initialDiscoveryShards.add(new StreamShardHandle(shardMetadata.getStreamName(), shard));
	}

	final TestFetcher<String> fetcher = new TestFetcher<>(
		Collections.singletonList(TEST_STREAM_NAME),
		new TestSourceContext<>(),
		new TestRuntimeContext(true, 1, 0),
		TestUtils.getStandardProperties(),
		new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()),
		state,
		initialDiscoveryShards);

	final DummyFlinkKinesisConsumer<String> consumer = new DummyFlinkKinesisConsumer<>(
		fetcher, new KinesisDeserializationSchemaWrapper<>(new SimpleStringSchema()));

	StreamSource<String, DummyFlinkKinesisConsumer<String>> consumerOperator = new StreamSource<>(consumer);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();
	testHarness.open();

	final AtomicReference<Throwable> error = new AtomicReference<>();

	// run the source asynchronously
	Thread runner = new Thread() {
		@Override
		public void run() {
			try {
				consumer.run(new TestSourceContext<>());
			} catch (Throwable t) {
				t.printStackTrace();
				error.set(t);
			}
		}
	};
	runner.start();

	fetcher.waitUntilRun();

	final OperatorSubtaskState snapshot;
	synchronized (testHarness.getCheckpointLock()) {
		snapshot = testHarness.snapshot(0L, 0L);
	}

	OperatorSnapshotUtil.writeStateHandle(snapshot, path);

	consumerOperator.close();
	runner.join();
}
 

/**
 * Test restoring from an empty state taken using a previous Flink version, when some partitions could be
 * found for topics.
 */
@Test
public void testRestoreFromEmptyStateWithPartitions() throws Exception {
	final List<KafkaTopicPartition> partitions = new ArrayList<>(PARTITION_STATE.keySet());

	final DummyFlinkKafkaConsumer<String> consumerFunction =
		new DummyFlinkKafkaConsumer<>(TOPICS, partitions, FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

	StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator =
			new StreamSource<>(consumerFunction);

	final AbstractStreamOperatorTestHarness<String> testHarness =
			new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

	testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

	testHarness.setup();

	// restore state from binary snapshot file
	testHarness.initializeState(
		OperatorSnapshotUtil.getResourceFilename(
			"kafka-consumer-migration-test-flink" + testMigrateVersion + "-empty-state-snapshot"));

	testHarness.open();

	// the expected state in "kafka-consumer-migration-test-flink1.x-snapshot-empty-state";
	// all new partitions after the snapshot are considered as partitions that were created while the
	// consumer wasn't running, and should start from the earliest offset.
	final HashMap<KafkaTopicPartition, Long> expectedSubscribedPartitionsWithStartOffsets = new HashMap<>();
	for (KafkaTopicPartition partition : PARTITION_STATE.keySet()) {
		expectedSubscribedPartitionsWithStartOffsets.put(partition, KafkaTopicPartitionStateSentinel.EARLIEST_OFFSET);
	}

	// assert that there are partitions and is identical to expected list
	assertTrue(consumerFunction.getSubscribedPartitionsToStartOffsets() != null);
	assertTrue(!consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());
	assertEquals(expectedSubscribedPartitionsWithStartOffsets, consumerFunction.getSubscribedPartitionsToStartOffsets());

	// the new partitions should have been considered as restored state
	assertTrue(consumerFunction.getRestoredState() != null);
	assertTrue(!consumerFunction.getSubscribedPartitionsToStartOffsets().isEmpty());
	for (Map.Entry<KafkaTopicPartition, Long> expectedEntry : expectedSubscribedPartitionsWithStartOffsets.entrySet()) {
		assertEquals(expectedEntry.getValue(), consumerFunction.getRestoredState().get(expectedEntry.getKey()));
	}

	consumerOperator.close();
	consumerOperator.cancel();
}
 

private void writeSnapshot(String path, HashMap<KafkaTopicPartition, Long> state) throws Exception {

		final OneShotLatch latch = new OneShotLatch();
		final AbstractFetcher<String, ?> fetcher = mock(AbstractFetcher.class);

		doAnswer(new Answer<Void>() {
			@Override
			public Void answer(InvocationOnMock invocation) throws Throwable {
				latch.trigger();
				return null;
			}
		}).when(fetcher).runFetchLoop();

		when(fetcher.snapshotCurrentState()).thenReturn(state);

		final List<KafkaTopicPartition> partitions = new ArrayList<>(PARTITION_STATE.keySet());

		final DummyFlinkKafkaConsumer<String> consumerFunction =
			new DummyFlinkKafkaConsumer<>(fetcher, TOPICS, partitions, FlinkKafkaConsumerBase.PARTITION_DISCOVERY_DISABLED);

		StreamSource<String, DummyFlinkKafkaConsumer<String>> consumerOperator =
				new StreamSource<>(consumerFunction);

		final AbstractStreamOperatorTestHarness<String> testHarness =
				new AbstractStreamOperatorTestHarness<>(consumerOperator, 1, 1, 0);

		testHarness.setTimeCharacteristic(TimeCharacteristic.ProcessingTime);

		testHarness.setup();
		testHarness.open();

		final Throwable[] error = new Throwable[1];

		// run the source asynchronously
		Thread runner = new Thread() {
			@Override
			public void run() {
				try {
					consumerFunction.run(new DummySourceContext() {
						@Override
						public void collect(String element) {

						}
					});
				}
				catch (Throwable t) {
					t.printStackTrace();
					error[0] = t;
				}
			}
		};
		runner.start();

		if (!latch.isTriggered()) {
			latch.await();
		}

		final OperatorSubtaskState snapshot;
		synchronized (testHarness.getCheckpointLock()) {
			snapshot = testHarness.snapshot(0L, 0L);
		}

		OperatorSnapshotUtil.writeStateHandle(snapshot, path);

		consumerOperator.close();
		runner.join();
	}