/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.io.network.netty;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import org.apache.flink.runtime.event.TaskEvent;
import org.apache.flink.runtime.io.network.ConnectionID;
import org.apache.flink.runtime.io.network.netty.exception.LocalTransportException;
import org.apache.flink.runtime.io.network.partition.ResultPartitionID;
import org.apache.flink.runtime.io.network.partition.consumer.RemoteInputChannel;
import org.apache.flink.runtime.util.AtomicDisposableReferenceCounter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import static org.apache.flink.runtime.io.network.netty.NettyMessage.PartitionRequest;
import static org.apache.flink.runtime.io.network.netty.NettyMessage.TaskEventRequest;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* Partition request client for remote partition requests.
* <p>
* This client is shared by all remote input channels, which request a partition
* from the same {@link ConnectionID}.
*/
public class PartitionRequestClient {
private static final Logger LOG = LoggerFactory.getLogger(PartitionRequestClient.class);
private final Channel tcpChannel;
private final PartitionRequestClientHandler partitionRequestHandler;
private final ConnectionID connectionId;
private final PartitionRequestClientFactory clientFactory;
// If zero, the underlying TCP channel can be safely closed
private final AtomicDisposableReferenceCounter closeReferenceCounter = new AtomicDisposableReferenceCounter();
PartitionRequestClient(
Channel tcpChannel,
PartitionRequestClientHandler partitionRequestHandler,
ConnectionID connectionId,
PartitionRequestClientFactory clientFactory) {
this.tcpChannel = checkNotNull(tcpChannel);
this.partitionRequestHandler = checkNotNull(partitionRequestHandler);
this.connectionId = checkNotNull(connectionId);
this.clientFactory = checkNotNull(clientFactory);
}
boolean disposeIfNotUsed() {
return closeReferenceCounter.disposeIfNotUsed();
}
/**
* Increments the reference counter.
* <p>
* Note: the reference counter has to be incremented before returning the
* instance of this client to ensure correct closing logic.
*/
boolean incrementReferenceCounter() {
return closeReferenceCounter.increment();
}
/**
* Requests a remote intermediate result partition queue.
* <p>
* The request goes to the remote producer, for which this partition
* request client instance has been created.
*/
public ChannelFuture requestSubpartition(
final ResultPartitionID partitionId,
final int subpartitionIndex,
final RemoteInputChannel inputChannel,
int delayMs) throws IOException {
checkNotClosed();
LOG.debug("Requesting subpartition {} of partition {} with {} ms delay.",
subpartitionIndex, partitionId, delayMs);
partitionRequestHandler.addInputChannel(inputChannel);
final PartitionRequest request = new PartitionRequest(
partitionId, subpartitionIndex, inputChannel.getInputChannelId());
final ChannelFutureListener listener = new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (!future.isSuccess()) {
partitionRequestHandler.removeInputChannel(inputChannel);
inputChannel.onError(
new LocalTransportException(
"Sending the partition request failed.",
future.channel().localAddress(), future.cause()
));
}
}
};
if (delayMs == 0) {
ChannelFuture f = tcpChannel.writeAndFlush(request);
f.addListener(listener);
return f;
}
else {
final ChannelFuture[] f = new ChannelFuture[1];
tcpChannel.eventLoop().schedule(new Runnable() {
@Override
public void run() {
f[0] = tcpChannel.writeAndFlush(request);
f[0].addListener(listener);
}
}, delayMs, TimeUnit.MILLISECONDS);
return f[0];
}
}
/**
* Sends a task event backwards to an intermediate result partition producer.
* <p>
* Backwards task events flow between readers and writers and therefore
* will only work when both are running at the same time, which is only
* guaranteed to be the case when both the respective producer and
* consumer task run pipelined.
*/
public void sendTaskEvent(ResultPartitionID partitionId, TaskEvent event, final RemoteInputChannel inputChannel) throws IOException {
checkNotClosed();
tcpChannel.writeAndFlush(new TaskEventRequest(event, partitionId, inputChannel.getInputChannelId()))
.addListener(
new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (!future.isSuccess()) {
inputChannel.onError(new LocalTransportException(
"Sending the task event failed.",
future.channel().localAddress(), future.cause()
));
}
}
});
}
public void close(RemoteInputChannel inputChannel) throws IOException {
partitionRequestHandler.removeInputChannel(inputChannel);
if (closeReferenceCounter.decrement()) {
// Close the TCP connection. Send a close request msg to ensure
// that outstanding backwards task events are not discarded.
tcpChannel.writeAndFlush(new NettyMessage.CloseRequest())
.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
// Make sure to remove the client from the factory
clientFactory.destroyPartitionRequestClient(connectionId, this);
}
else {
partitionRequestHandler.cancelRequestFor(inputChannel.getInputChannelId());
}
}
private void checkNotClosed() throws IOException {
if (closeReferenceCounter.isDisposed()) {
throw new LocalTransportException("Channel closed.", tcpChannel.localAddress());
}
}
}