/**
* 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.s4.comm.tcp;
import java.net.InetSocketAddress;
import java.util.concurrent.Executors;
import org.apache.s4.base.Listener;
import org.apache.s4.base.Receiver;
import org.apache.s4.comm.DeserializerExecutorFactory;
import org.apache.s4.comm.topology.Assignment;
import org.apache.s4.comm.topology.ClusterNode;
import org.jboss.netty.bootstrap.ServerBootstrap;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFactory;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelPipelineFactory;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelHandler;
import org.jboss.netty.channel.group.ChannelGroup;
import org.jboss.netty.channel.group.DefaultChannelGroup;
import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;
import org.jboss.netty.handler.codec.frame.LengthFieldBasedFrameDecoder;
import org.jboss.netty.handler.execution.ExecutionHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import com.google.inject.name.Named;
/**
* Receives messages through TCP for the assigned subcluster.
*
*/
@Singleton
public class TCPListener implements Listener {
private static final Logger logger = LoggerFactory.getLogger(TCPListener.class);
private ClusterNode node;
private ServerBootstrap bootstrap;
private final ChannelGroup channels = new DefaultChannelGroup();
private final int nettyTimeout;
/**
*
* @param assignment
* partition assignment information
* @param timeout
* netty timeout
* @param receiver
* link to the application layer
* @param deserializerExecutorFactory
* factory for creating deserialization thread pool
*/
@Inject
public TCPListener(Assignment assignment, @Named("s4.comm.timeout") int timeout, final Receiver receiver,
final DeserializerExecutorFactory deserializerExecutorFactory) {
// wait for an assignment
node = assignment.assignClusterNode();
nettyTimeout = timeout;
ChannelFactory factory = new NioServerSocketChannelFactory(Executors.newCachedThreadPool(),
Executors.newCachedThreadPool());
bootstrap = new ServerBootstrap(factory);
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
@Override
public ChannelPipeline getPipeline() {
ChannelPipeline p = Channels.pipeline();
p.addLast("decoder", new LengthFieldBasedFrameDecoder(999999, 0, 4, 0, 4));
p.addLast("executionhandler", new ExecutionHandler(deserializerExecutorFactory.create()));
p.addLast("receiver", new EventDecoderHandler(receiver));
return p;
}
});
bootstrap.setOption("child.tcpNoDelay", true);
bootstrap.setOption("child.keepAlive", true);
bootstrap.setOption("child.reuseAddress", true);
bootstrap.setOption("child.connectTimeoutMillis", nettyTimeout);
bootstrap.setOption("readWriteFair", true);
Channel c = bootstrap.bind(new InetSocketAddress(node.getPort()));
channels.add(c);
}
@Override
public int getPartitionId() {
return node.getPartition();
}
@Override
public void close() {
try {
channels.close().await();
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
bootstrap.releaseExternalResources();
}
public class EventDecoderHandler extends SimpleChannelHandler {
private final Receiver receiver;
public EventDecoderHandler(Receiver receiver) {
this.receiver = receiver;
}
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) {
channels.add(e.getChannel());
ChannelBuffer buffer = (ChannelBuffer) e.getMessage();
receiver.receive(buffer.toByteBuffer());
}
@Override
public void exceptionCaught(ChannelHandlerContext context, ExceptionEvent event) {
logger.error("Error", event.getCause());
Channel c = context.getChannel();
c.close().addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
channels.remove(future.getChannel());
} else {
logger.error("FAILED to close channel");
}
}
});
}
@Override
public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
super.channelClosed(ctx, e);
}
}
}