org.apache.flink.runtime.io.network.util.TestBufferFactory Java Examples

/**
 * Tests a fix for FLINK-1627.
 *
 * <p> FLINK-1627 discovered a race condition, which could lead to an infinite loop when a
 * receiver was cancelled during a certain time of decoding a message. The test reproduces the
 * input, which lead to the infinite loop: when the handler gets a reference to the buffer
 * provider of the receiving input channel, but the respective input channel is released (and
 * the corresponding buffer provider destroyed), the handler did not notice this.
 *
 * @see <a href="https://issues.apache.org/jira/browse/FLINK-1627">FLINK-1627</a>
 */
@Test(timeout = 60000)
@SuppressWarnings("unchecked")
public void testReleaseInputChannelDuringDecode() throws Exception {
	// Mocks an input channel in a state as it was released during a decode.
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(null);
	when(bufferProvider.isDestroyed()).thenReturn(true);
	when(bufferProvider.addBufferListener(any(BufferListener.class))).thenReturn(false);

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final BufferResponse receivedBuffer = createBufferResponse(
			TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE), 0, inputChannel.getInputChannelId(), 2);

	final PartitionRequestClientHandler client = new PartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);
}
 

/**
 * Tests a fix for FLINK-1627.
 *
 * <p> FLINK-1627 discovered a race condition, which could lead to an infinite loop when a
 * receiver was cancelled during a certain time of decoding a message. The test reproduces the
 * input, which lead to the infinite loop: when the handler gets a reference to the buffer
 * provider of the receiving input channel, but the respective input channel is released (and
 * the corresponding buffer provider destroyed), the handler did not notice this.
 *
 * @see <a href="https://issues.apache.org/jira/browse/FLINK-1627">FLINK-1627</a>
 */
@Test(timeout = 60000)
@SuppressWarnings("unchecked")
public void testReleaseInputChannelDuringDecode() throws Exception {
	// Mocks an input channel in a state as it was released during a decode.
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(null);
	when(bufferProvider.isDestroyed()).thenReturn(true);
	when(bufferProvider.addBufferListener(any(BufferListener.class))).thenReturn(false);

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final BufferResponse receivedBuffer = createBufferResponse(
			TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE), 0, inputChannel.getInputChannelId(), 2);

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);
}
 

/**
 * Tests a fix for FLINK-1627.
 *
 * <p> FLINK-1627 discovered a race condition, which could lead to an infinite loop when a
 * receiver was cancelled during a certain time of decoding a message. The test reproduces the
 * input, which lead to the infinite loop: when the handler gets a reference to the buffer
 * provider of the receiving input channel, but the respective input channel is released (and
 * the corresponding buffer provider destroyed), the handler did not notice this.
 *
 * @see <a href="https://issues.apache.org/jira/browse/FLINK-1627">FLINK-1627</a>
 */
@Test(timeout = 60000)
@SuppressWarnings("unchecked")
public void testReleaseInputChannelDuringDecode() throws Exception {
	// Mocks an input channel in a state as it was released during a decode.
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(null);
	when(bufferProvider.isDestroyed()).thenReturn(true);
	when(bufferProvider.addBufferListener(any(BufferListener.class))).thenReturn(false);

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final BufferResponse receivedBuffer = createBufferResponse(
			TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE), 0, inputChannel.getInputChannelId(), 2);

	final PartitionRequestClientHandler client = new PartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);
}
 

/**
 * Verifies that {@link RemoteInputChannel#onError(Throwable)} is called when a
 * {@link BufferResponse} is received but no available buffer in input channel.
 */
@Test
public void testThrowExceptionForNoAvailableBuffer() throws Exception {
	final SingleInputGate inputGate = createSingleInputGate(1);
	final RemoteInputChannel inputChannel = spy(InputChannelBuilder.newBuilder().buildRemoteAndSetToGate(inputGate));

	final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();
	handler.addInputChannel(inputChannel);

	assertEquals("There should be no buffers available in the channel.",
			0, inputChannel.getNumberOfAvailableBuffers());

	final BufferResponse bufferResponse = createBufferResponse(
		TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE), 0, inputChannel.getInputChannelId(), 2);
	handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

	verify(inputChannel, times(1)).onError(any(IllegalStateException.class));
}
 

/**
 * Tests a fix for FLINK-1627.
 *
 * <p> FLINK-1627 discovered a race condition, which could lead to an infinite loop when a
 * receiver was cancelled during a certain time of decoding a message. The test reproduces the
 * input, which lead to the infinite loop: when the handler gets a reference to the buffer
 * provider of the receiving input channel, but the respective input channel is released (and
 * the corresponding buffer provider destroyed), the handler did not notice this.
 *
 * @see <a href="https://issues.apache.org/jira/browse/FLINK-1627">FLINK-1627</a>
 */
@Test(timeout = 60000)
@SuppressWarnings("unchecked")
public void testReleaseInputChannelDuringDecode() throws Exception {
	// Mocks an input channel in a state as it was released during a decode.
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(null);
	when(bufferProvider.isDestroyed()).thenReturn(true);
	when(bufferProvider.addBufferListener(any(BufferListener.class))).thenReturn(false);

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	final BufferResponse receivedBuffer = createBufferResponse(
		TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE),
		0,
		inputChannel.getInputChannelId(),
		2,
		new NetworkBufferAllocator(client));

	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);
}
 

/**
 * Verifies that {@link RemoteInputChannel#onError(Throwable)} is called when a
 * {@link BufferResponse} is received but no available buffer in input channel.
 */
@Test
public void testThrowExceptionForNoAvailableBuffer() throws Exception {
	final SingleInputGate inputGate = createSingleInputGate();
	final RemoteInputChannel inputChannel = spy(createRemoteInputChannel(inputGate));

	final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();
	handler.addInputChannel(inputChannel);

	assertEquals("There should be no buffers available in the channel.",
			0, inputChannel.getNumberOfAvailableBuffers());

	final BufferResponse bufferResponse = createBufferResponse(
		TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE), 0, inputChannel.getInputChannelId(), 2);
	handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

	verify(inputChannel, times(1)).onError(any(IllegalStateException.class));
}
 

/**
 * Verifies that {@link RemoteInputChannel#onError(Throwable)} is called when a
 * {@link BufferResponse} is received but no available buffer in input channel.
 */
@Test
public void testThrowExceptionForNoAvailableBuffer() throws Exception {
	final SingleInputGate inputGate = createSingleInputGate(1);
	final RemoteInputChannel inputChannel = spy(InputChannelBuilder.newBuilder().buildRemoteChannel(inputGate));

	final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();
	handler.addInputChannel(inputChannel);

	assertEquals("There should be no buffers available in the channel.",
			0, inputChannel.getNumberOfAvailableBuffers());

	final BufferResponse bufferResponse = createBufferResponse(
		TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE),
		0,
		inputChannel.getInputChannelId(),
		2,
		new NetworkBufferAllocator(handler));
	assertNull(bufferResponse.getBuffer());

	handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);
	verify(inputChannel, times(1)).onError(any(IllegalStateException.class));
}
 

/**
 * Tests a fix for FLINK-1627.
 *
 * <p> FLINK-1627 discovered a race condition, which could lead to an infinite loop when a
 * receiver was cancelled during a certain time of decoding a message. The test reproduces the
 * input, which lead to the infinite loop: when the handler gets a reference to the buffer
 * provider of the receiving input channel, but the respective input channel is released (and
 * the corresponding buffer provider destroyed), the handler did not notice this.
 *
 * @see <a href="https://issues.apache.org/jira/browse/FLINK-1627">FLINK-1627</a>
 */
@Test(timeout = 60000)
@SuppressWarnings("unchecked")
public void testReleaseInputChannelDuringDecode() throws Exception {
	// Mocks an input channel in a state as it was released during a decode.
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(null);
	when(bufferProvider.isDestroyed()).thenReturn(true);
	when(bufferProvider.addBufferListener(any(BufferListener.class))).thenReturn(false);

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final BufferResponse receivedBuffer = createBufferResponse(
			TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE), 0, inputChannel.getInputChannelId(), 2);

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);
}
 

@Test
public void testExceptionOnReordering() throws Exception {
	// Setup
	final SingleInputGate inputGate = createSingleInputGate(1);
	final RemoteInputChannel inputChannel = createRemoteInputChannel(inputGate);
	final Buffer buffer = TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE);

	// The test
	inputChannel.onBuffer(buffer.retainBuffer(), 0, -1);

	// This does not yet throw the exception, but sets the error at the channel.
	inputChannel.onBuffer(buffer, 29, -1);

	try {
		inputChannel.getNextBuffer();

		fail("Did not throw expected exception after enqueuing an out-of-order buffer.");
	}
	catch (Exception expected) {
		assertFalse(buffer.isRecycled());
		// free remaining buffer instances
		inputChannel.releaseAllResources();
		assertTrue(buffer.isRecycled());
	}
}
 

/**
 * Verifies that {@link RemoteInputChannel#onBuffer(Buffer, int, int)} is called when a
 * {@link BufferResponse} is received.
 */
@Test
public void testReceiveBuffer() throws Exception {
	final NetworkBufferPool networkBufferPool = new NetworkBufferPool(10, 32, 2);
	final SingleInputGate inputGate = createSingleInputGate(1, networkBufferPool);
	final RemoteInputChannel inputChannel = InputChannelBuilder.newBuilder().buildRemoteChannel(inputGate);
	try {
		inputGate.setInputChannels(inputChannel);
		final BufferPool bufferPool = networkBufferPool.createBufferPool(8, 8);
		inputGate.setBufferPool(bufferPool);
		inputGate.assignExclusiveSegments();

		final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();
		handler.addInputChannel(inputChannel);

		final int backlog = 2;
		final BufferResponse bufferResponse = createBufferResponse(
			TestBufferFactory.createBuffer(32),
			0,
			inputChannel.getInputChannelId(),
			backlog,
			new NetworkBufferAllocator(handler));
		handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

		assertEquals(1, inputChannel.getNumberOfQueuedBuffers());
		assertEquals(2, inputChannel.getSenderBacklog());
	} finally {
		releaseResource(inputGate, networkBufferPool);
	}
}
 

/**
 * Tests a fix for FLINK-1761.
 *
 * <p>FLINK-1761 discovered an IndexOutOfBoundsException, when receiving buffers of size 0.
 */
@Test
public void testReceiveEmptyBuffer() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	// An empty buffer of size 0
	final Buffer emptyBuffer = TestBufferFactory.createBuffer(0);

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	final int backlog = 2;
	final BufferResponse receivedBuffer = createBufferResponse(
		emptyBuffer,
		0,
		inputChannel.getInputChannelId(),
		backlog,
		new NetworkBufferAllocator(client));

	// Read the empty buffer
	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);

	// This should not throw an exception
	verify(inputChannel, never()).onError(any(Throwable.class));
	verify(inputChannel, times(1)).onEmptyBuffer(0, backlog);
}
 

/**
 * Verifies that {@link RemoteInputChannel#onFailedPartitionRequest()} is called when a
 * {@link PartitionNotFoundException} is received.
 */
@Test
public void testReceivePartitionNotFoundException() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final ErrorResponse partitionNotFound = new ErrorResponse(
		new PartitionNotFoundException(new ResultPartitionID()),
		inputChannel.getInputChannelId());

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Mock channel context
	ChannelHandlerContext ctx = mock(ChannelHandlerContext.class);
	when(ctx.channel()).thenReturn(mock(Channel.class));

	client.channelActive(ctx);

	client.channelRead(ctx, partitionNotFound);

	verify(inputChannel, times(1)).onFailedPartitionRequest();
}
 

@Nullable
@Override
public BufferAndBacklog getNextBuffer() {
	int buffers = buffersInBacklog.decrementAndGet();
	return new BufferAndBacklog(
		TestBufferFactory.createBuffer(10),
		buffers > 0,
		buffers,
		false);
}
 

@Test
public void testExceptionOnReordering() throws Exception {
	// Setup
	final SingleInputGate inputGate = mock(SingleInputGate.class);
	final RemoteInputChannel inputChannel = createRemoteInputChannel(inputGate);
	final Buffer buffer = TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE);

	// The test
	inputChannel.onBuffer(buffer.retainBuffer(), 0, -1);

	// This does not yet throw the exception, but sets the error at the channel.
	inputChannel.onBuffer(buffer, 29, -1);

	try {
		inputChannel.getNextBuffer();

		fail("Did not throw expected exception after enqueuing an out-of-order buffer.");
	}
	catch (Exception expected) {
		assertFalse(buffer.isRecycled());
		// free remaining buffer instances
		inputChannel.releaseAllResources();
		assertTrue(buffer.isRecycled());
	}

	// Need to notify the input gate for the out-of-order buffer as well. Otherwise the
	// receiving task will not notice the error.
	verify(inputGate, times(2)).notifyChannelNonEmpty(eq(inputChannel));
}
 

/**
 * Verifies that {@link RemoteInputChannel#onFailedPartitionRequest()} is called when a
 * {@link PartitionNotFoundException} is received.
 */
@Test
public void testReceivePartitionNotFoundException() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final ErrorResponse partitionNotFound = new ErrorResponse(
		new PartitionNotFoundException(new ResultPartitionID()),
		inputChannel.getInputChannelId());

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Mock channel context
	ChannelHandlerContext ctx = mock(ChannelHandlerContext.class);
	when(ctx.channel()).thenReturn(mock(Channel.class));

	client.channelActive(ctx);

	client.channelRead(ctx, partitionNotFound);

	verify(inputChannel, times(1)).onFailedPartitionRequest();
}
 

@Test
public void testDoNotFailHandlerOnSingleChannelFailure() throws Exception {
	// Setup
	final int bufferSize = 1024;
	final String expectedMessage = "test exception on buffer";
	final NetworkBufferPool networkBufferPool = new NetworkBufferPool(10, bufferSize, 2);
	final SingleInputGate inputGate = createSingleInputGate(1, networkBufferPool);
	final RemoteInputChannel inputChannel = new TestRemoteInputChannelForError(inputGate, expectedMessage);
	final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();

	try {
		inputGate.setInputChannels(inputChannel);
		inputGate.assignExclusiveSegments();
		inputGate.requestPartitions();
		handler.addInputChannel(inputChannel);

		final BufferResponse bufferResponse = createBufferResponse(
			TestBufferFactory.createBuffer(bufferSize),
			0,
			inputChannel.getInputChannelId(),
			1,
			new NetworkBufferAllocator(handler));

		// It will trigger an expected exception from TestRemoteInputChannelForError#onBuffer
		handler.channelRead(null, bufferResponse);

		// The handler should not be tagged as error for above excepted exception
		handler.checkError();

		try {
			// The input channel should be tagged as error and the respective exception is thrown via #getNext
			inputGate.getNext();
		} catch (IOException ignored) {
			assertEquals(expectedMessage, ignored.getMessage());
		}
	} finally {
		// Cleanup
		releaseResource(inputGate, networkBufferPool);
	}
}
 

@Nullable
@Override
public BufferAndBacklog getNextBuffer() {
	int buffers = buffersInBacklog.decrementAndGet();
	return new BufferAndBacklog(
		TestBufferFactory.createBuffer(10),
		buffers > 0,
		buffers,
		false);
}
 

/**
 * Tests a fix for FLINK-1761.
 *
 * <p>FLINK-1761 discovered an IndexOutOfBoundsException, when receiving buffers of size 0.
 */
@Test
public void testReceiveEmptyBuffer() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	// An empty buffer of size 0
	final Buffer emptyBuffer = TestBufferFactory.createBuffer(0);

	final int backlog = 2;
	final BufferResponse receivedBuffer = createBufferResponse(
		emptyBuffer, 0, inputChannel.getInputChannelId(), backlog);

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Read the empty buffer
	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);

	// This should not throw an exception
	verify(inputChannel, never()).onError(any(Throwable.class));
	verify(inputChannel, times(1)).onEmptyBuffer(0, backlog);
}
 

/**
 * Verifies that {@link RemoteInputChannel#onBuffer(Buffer, int, int)} is called when a
 * {@link BufferResponse} is received.
 */
@Test
public void testReceiveBuffer() throws Exception {
	final NetworkBufferPool networkBufferPool = new NetworkBufferPool(10, 32, 2);
	final SingleInputGate inputGate = createSingleInputGate(1);
	final RemoteInputChannel inputChannel = InputChannelBuilder.newBuilder()
		.setMemorySegmentProvider(networkBufferPool)
		.buildRemoteAndSetToGate(inputGate);
	try {
		final BufferPool bufferPool = networkBufferPool.createBufferPool(8, 8);
		inputGate.setBufferPool(bufferPool);
		inputGate.assignExclusiveSegments();

		final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();
		handler.addInputChannel(inputChannel);

		final int backlog = 2;
		final BufferResponse bufferResponse = createBufferResponse(
			TestBufferFactory.createBuffer(32), 0, inputChannel.getInputChannelId(), backlog);
		handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

		assertEquals(1, inputChannel.getNumberOfQueuedBuffers());
		assertEquals(2, inputChannel.getSenderBacklog());
	} finally {
		// Release all the buffer resources
		inputGate.close();

		networkBufferPool.destroyAllBufferPools();
		networkBufferPool.destroy();
	}
}
 

/**
 * Verifies that {@link RemoteInputChannel#onBuffer(Buffer, int, int)} is called when a
 * {@link BufferResponse} is received.
 */
@Test
public void testReceiveBuffer() throws Exception {
	final NetworkBufferPool networkBufferPool = new NetworkBufferPool(10, 32, 2);
	final SingleInputGate inputGate = createSingleInputGate(1);
	final RemoteInputChannel inputChannel = InputChannelBuilder.newBuilder()
		.setMemorySegmentProvider(networkBufferPool)
		.buildRemoteAndSetToGate(inputGate);
	try {
		final BufferPool bufferPool = networkBufferPool.createBufferPool(8, 8);
		inputGate.setBufferPool(bufferPool);
		inputGate.assignExclusiveSegments();

		final PartitionRequestClientHandler handler = new PartitionRequestClientHandler();
		handler.addInputChannel(inputChannel);

		final int backlog = 2;
		final BufferResponse bufferResponse = createBufferResponse(
			TestBufferFactory.createBuffer(32), 0, inputChannel.getInputChannelId(), backlog);
		handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

		assertEquals(1, inputChannel.getNumberOfQueuedBuffers());
	} finally {
		// Release all the buffer resources
		inputGate.close();

		networkBufferPool.destroyAllBufferPools();
		networkBufferPool.destroy();
	}
}
 

/**
 * Tests a fix for FLINK-1761.
 *
 * <p>FLINK-1761 discovered an IndexOutOfBoundsException, when receiving buffers of size 0.
 */
@Test
public void testReceiveEmptyBuffer() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	// An empty buffer of size 0
	final Buffer emptyBuffer = TestBufferFactory.createBuffer(0);

	final int backlog = -1;
	final BufferResponse receivedBuffer = createBufferResponse(
		emptyBuffer, 0, inputChannel.getInputChannelId(), backlog);

	final PartitionRequestClientHandler client = new PartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Read the empty buffer
	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);

	// This should not throw an exception
	verify(inputChannel, never()).onError(any(Throwable.class));
	verify(inputChannel, times(1)).onEmptyBuffer(0, backlog);
}
 

/**
 * Verifies that {@link RemoteInputChannel#onBuffer(Buffer, int, int)} is called when a
 * {@link BufferResponse} is received.
 */
@Test
public void testReceiveBuffer() throws Exception {
	final NetworkBufferPool networkBufferPool = new NetworkBufferPool(10, 32);
	final SingleInputGate inputGate = createSingleInputGate();
	final RemoteInputChannel inputChannel = createRemoteInputChannel(inputGate);
	try {
		final BufferPool bufferPool = networkBufferPool.createBufferPool(8, 8);
		inputGate.setBufferPool(bufferPool);
		final int numExclusiveBuffers = 2;
		inputGate.assignExclusiveSegments(networkBufferPool, numExclusiveBuffers);

		final PartitionRequestClientHandler handler = new PartitionRequestClientHandler();
		handler.addInputChannel(inputChannel);

		final int backlog = 2;
		final BufferResponse bufferResponse = createBufferResponse(
			TestBufferFactory.createBuffer(32), 0, inputChannel.getInputChannelId(), backlog);
		handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

		assertEquals(1, inputChannel.getNumberOfQueuedBuffers());
	} finally {
		// Release all the buffer resources
		inputGate.releaseAllResources();

		networkBufferPool.destroyAllBufferPools();
		networkBufferPool.destroy();
	}
}
 

/**
 * Verifies that {@link RemoteInputChannel#onFailedPartitionRequest()} is called when a
 * {@link PartitionNotFoundException} is received.
 */
@Test
public void testReceivePartitionNotFoundException() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final ErrorResponse partitionNotFound = new ErrorResponse(
		new PartitionNotFoundException(new ResultPartitionID()),
		inputChannel.getInputChannelId());

	final PartitionRequestClientHandler client = new PartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Mock channel context
	ChannelHandlerContext ctx = mock(ChannelHandlerContext.class);
	when(ctx.channel()).thenReturn(mock(Channel.class));

	client.channelActive(ctx);

	client.channelRead(ctx, partitionNotFound);

	verify(inputChannel, times(1)).onFailedPartitionRequest();
}
 

/**
 * Tests a fix for FLINK-1761.
 *
 * <p>FLINK-1761 discovered an IndexOutOfBoundsException, when receiving buffers of size 0.
 */
@Test
public void testReceiveEmptyBuffer() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	// An empty buffer of size 0
	final Buffer emptyBuffer = TestBufferFactory.createBuffer(0);

	final int backlog = 2;
	final BufferResponse receivedBuffer = createBufferResponse(
		emptyBuffer, 0, inputChannel.getInputChannelId(), backlog);

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Read the empty buffer
	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);

	// This should not throw an exception
	verify(inputChannel, never()).onError(any(Throwable.class));
	verify(inputChannel, times(1)).onEmptyBuffer(0, backlog);
}
 

/**
 * Verifies that {@link RemoteInputChannel#onBuffer(Buffer, int, int)} is called when a
 * {@link BufferResponse} is received.
 */
@Test
public void testReceiveBuffer() throws Exception {
	final NetworkBufferPool networkBufferPool = new NetworkBufferPool(10, 32);
	final SingleInputGate inputGate = createSingleInputGate();
	final RemoteInputChannel inputChannel = createRemoteInputChannel(inputGate);
	try {
		final BufferPool bufferPool = networkBufferPool.createBufferPool(8, 8);
		inputGate.setBufferPool(bufferPool);
		final int numExclusiveBuffers = 2;
		inputGate.assignExclusiveSegments(networkBufferPool, numExclusiveBuffers);

		final CreditBasedPartitionRequestClientHandler handler = new CreditBasedPartitionRequestClientHandler();
		handler.addInputChannel(inputChannel);

		final int backlog = 2;
		final BufferResponse bufferResponse = createBufferResponse(
			TestBufferFactory.createBuffer(32), 0, inputChannel.getInputChannelId(), backlog);
		handler.channelRead(mock(ChannelHandlerContext.class), bufferResponse);

		assertEquals(1, inputChannel.getNumberOfQueuedBuffers());
		assertEquals(2, inputChannel.getSenderBacklog());
	} finally {
		// Release all the buffer resources
		inputGate.releaseAllResources();

		networkBufferPool.destroyAllBufferPools();
		networkBufferPool.destroy();
	}
}
 

/**
 * Verifies that {@link RemoteInputChannel#onFailedPartitionRequest()} is called when a
 * {@link PartitionNotFoundException} is received.
 */
@Test
public void testReceivePartitionNotFoundException() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final ErrorResponse partitionNotFound = new ErrorResponse(
		new PartitionNotFoundException(new ResultPartitionID()),
		inputChannel.getInputChannelId());

	final CreditBasedPartitionRequestClientHandler client = new CreditBasedPartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Mock channel context
	ChannelHandlerContext ctx = mock(ChannelHandlerContext.class);
	when(ctx.channel()).thenReturn(mock(Channel.class));

	client.channelActive(ctx);

	client.channelRead(ctx, partitionNotFound);

	verify(inputChannel, times(1)).onFailedPartitionRequest();
}
 

/**
 * Verifies that {@link RemoteInputChannel#onFailedPartitionRequest()} is called when a
 * {@link PartitionNotFoundException} is received.
 */
@Test
public void testReceivePartitionNotFoundException() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	final ErrorResponse partitionNotFound = new ErrorResponse(
		new PartitionNotFoundException(new ResultPartitionID()),
		inputChannel.getInputChannelId());

	final PartitionRequestClientHandler client = new PartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Mock channel context
	ChannelHandlerContext ctx = mock(ChannelHandlerContext.class);
	when(ctx.channel()).thenReturn(mock(Channel.class));

	client.channelActive(ctx);

	client.channelRead(ctx, partitionNotFound);

	verify(inputChannel, times(1)).onFailedPartitionRequest();
}
 

/**
 * Tests a fix for FLINK-1761.
 *
 * <p>FLINK-1761 discovered an IndexOutOfBoundsException, when receiving buffers of size 0.
 */
@Test
public void testReceiveEmptyBuffer() throws Exception {
	// Minimal mock of a remote input channel
	final BufferProvider bufferProvider = mock(BufferProvider.class);
	when(bufferProvider.requestBuffer()).thenReturn(TestBufferFactory.createBuffer(0));

	final RemoteInputChannel inputChannel = mock(RemoteInputChannel.class);
	when(inputChannel.getInputChannelId()).thenReturn(new InputChannelID());
	when(inputChannel.getBufferProvider()).thenReturn(bufferProvider);

	// An empty buffer of size 0
	final Buffer emptyBuffer = TestBufferFactory.createBuffer(0);

	final int backlog = -1;
	final BufferResponse receivedBuffer = createBufferResponse(
		emptyBuffer, 0, inputChannel.getInputChannelId(), backlog);

	final PartitionRequestClientHandler client = new PartitionRequestClientHandler();
	client.addInputChannel(inputChannel);

	// Read the empty buffer
	client.channelRead(mock(ChannelHandlerContext.class), receivedBuffer);

	// This should not throw an exception
	verify(inputChannel, never()).onError(any(Throwable.class));
	verify(inputChannel, times(1)).onEmptyBuffer(0, backlog);
}
 

@Test
public void testExceptionOnReordering() throws Exception {
	// Setup
	final SingleInputGate inputGate = mock(SingleInputGate.class);
	final RemoteInputChannel inputChannel = createRemoteInputChannel(inputGate);
	final Buffer buffer = TestBufferFactory.createBuffer(TestBufferFactory.BUFFER_SIZE);

	// The test
	inputChannel.onBuffer(buffer.retainBuffer(), 0, -1);

	// This does not yet throw the exception, but sets the error at the channel.
	inputChannel.onBuffer(buffer, 29, -1);

	try {
		inputChannel.getNextBuffer();

		fail("Did not throw expected exception after enqueuing an out-of-order buffer.");
	}
	catch (Exception expected) {
		assertFalse(buffer.isRecycled());
		// free remaining buffer instances
		inputChannel.releaseAllResources();
		assertTrue(buffer.isRecycled());
	}

	// Need to notify the input gate for the out-of-order buffer as well. Otherwise the
	// receiving task will not notice the error.
	verify(inputGate, times(2)).notifyChannelNonEmpty(eq(inputChannel));
}
 

@Nullable
@Override
public BufferAndBacklog getNextBuffer() {
	int buffers = buffersInBacklog.decrementAndGet();
	return new BufferAndBacklog(
		TestBufferFactory.createBuffer(10),
		buffers > 0,
		buffers,
		false);
}