| package org.onlab.netty; |
| |
| import java.io.IOException; |
| import java.net.UnknownHostException; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ConcurrentMap; |
| import java.util.concurrent.TimeUnit; |
| |
| import io.netty.bootstrap.Bootstrap; |
| import io.netty.bootstrap.ServerBootstrap; |
| import io.netty.buffer.PooledByteBufAllocator; |
| import io.netty.channel.Channel; |
| import io.netty.channel.ChannelFuture; |
| import io.netty.channel.ChannelHandlerContext; |
| import io.netty.channel.ChannelInitializer; |
| import io.netty.channel.ChannelOption; |
| import io.netty.channel.EventLoopGroup; |
| import io.netty.channel.SimpleChannelInboundHandler; |
| import io.netty.channel.nio.NioEventLoopGroup; |
| import io.netty.channel.socket.SocketChannel; |
| import io.netty.channel.socket.nio.NioServerSocketChannel; |
| import io.netty.channel.socket.nio.NioSocketChannel; |
| |
| import org.apache.commons.lang.math.RandomUtils; |
| import org.apache.commons.pool.KeyedObjectPool; |
| import org.apache.commons.pool.KeyedPoolableObjectFactory; |
| import org.apache.commons.pool.impl.GenericKeyedObjectPool; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.google.common.cache.Cache; |
| import com.google.common.cache.CacheBuilder; |
| |
| /** |
| * A Netty based implementation of MessagingService. |
| */ |
| public class NettyMessagingService implements MessagingService { |
| |
| private final Logger log = LoggerFactory.getLogger(getClass()); |
| |
| private KeyedObjectPool<Endpoint, Channel> channels = |
| new GenericKeyedObjectPool<Endpoint, Channel>(new OnosCommunicationChannelFactory()); |
| private final int port; |
| private final EventLoopGroup bossGroup = new NioEventLoopGroup(); |
| private final EventLoopGroup workerGroup = new NioEventLoopGroup(); |
| private final ConcurrentMap<String, MessageHandler> handlers = new ConcurrentHashMap<>(); |
| private Cache<Long, AsyncResponse<?>> responseFutures; |
| private final Endpoint localEp; |
| |
| protected Serializer serializer; |
| |
| public NettyMessagingService() { |
| // TODO: Default port should be configurable. |
| this(8080); |
| } |
| |
| // FIXME: Constructor should not throw exceptions. |
| public NettyMessagingService(int port) { |
| this.port = port; |
| try { |
| localEp = new Endpoint(java.net.InetAddress.getLocalHost().getHostName(), port); |
| } catch (UnknownHostException e) { |
| // bailing out. |
| throw new RuntimeException(e); |
| } |
| } |
| |
| public void activate() throws Exception { |
| responseFutures = CacheBuilder.newBuilder() |
| .maximumSize(100000) |
| .weakValues() |
| // TODO: Once the entry expires, notify blocking threads (if any). |
| .expireAfterWrite(10, TimeUnit.MINUTES) |
| .build(); |
| startAcceptingConnections(); |
| } |
| |
| public void deactivate() throws Exception { |
| channels.close(); |
| bossGroup.shutdownGracefully(); |
| workerGroup.shutdownGracefully(); |
| } |
| |
| @Override |
| public void sendAsync(Endpoint ep, String type, Object payload) throws IOException { |
| InternalMessage message = new InternalMessage.Builder(this) |
| .withId(RandomUtils.nextLong()) |
| .withSender(localEp) |
| .withType(type) |
| .withPayload(payload) |
| .build(); |
| sendAsync(ep, message); |
| } |
| |
| protected void sendAsync(Endpoint ep, InternalMessage message) throws IOException { |
| Channel channel = null; |
| try { |
| channel = channels.borrowObject(ep); |
| channel.eventLoop().execute(new WriteTask(channel, message)); |
| } catch (Exception e) { |
| throw new IOException(e); |
| } finally { |
| try { |
| channels.returnObject(ep, channel); |
| } catch (Exception e) { |
| log.warn("Error returning object back to the pool", e); |
| // ignored. |
| } |
| } |
| } |
| |
| @Override |
| public <T> Response<T> sendAndReceive(Endpoint ep, String type, Object payload) |
| throws IOException { |
| AsyncResponse<T> futureResponse = new AsyncResponse<T>(); |
| Long messageId = RandomUtils.nextLong(); |
| responseFutures.put(messageId, futureResponse); |
| InternalMessage message = new InternalMessage.Builder(this) |
| .withId(messageId) |
| .withSender(localEp) |
| .withType(type) |
| .withPayload(payload) |
| .build(); |
| sendAsync(ep, message); |
| return futureResponse; |
| } |
| |
| @Override |
| public void registerHandler(String type, MessageHandler handler) { |
| // TODO: Is this the right semantics for handler registration? |
| handlers.putIfAbsent(type, handler); |
| } |
| |
| public void unregisterHandler(String type) { |
| handlers.remove(type); |
| } |
| |
| private MessageHandler getMessageHandler(String type) { |
| return handlers.get(type); |
| } |
| |
| private void startAcceptingConnections() throws InterruptedException { |
| ServerBootstrap b = new ServerBootstrap(); |
| b.option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT); |
| b.group(bossGroup, workerGroup) |
| .channel(NioServerSocketChannel.class) |
| .childHandler(new OnosCommunicationChannelInitializer()) |
| .option(ChannelOption.SO_BACKLOG, 128) |
| .childOption(ChannelOption.SO_KEEPALIVE, true); |
| |
| // Bind and start to accept incoming connections. |
| b.bind(port).sync(); |
| } |
| |
| private class OnosCommunicationChannelFactory |
| implements KeyedPoolableObjectFactory<Endpoint, Channel> { |
| |
| @Override |
| public void activateObject(Endpoint endpoint, Channel channel) |
| throws Exception { |
| } |
| |
| @Override |
| public void destroyObject(Endpoint ep, Channel channel) throws Exception { |
| channel.close(); |
| } |
| |
| @Override |
| public Channel makeObject(Endpoint ep) throws Exception { |
| Bootstrap b = new Bootstrap(); |
| b.option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT); |
| b.group(workerGroup); |
| // TODO: Make this faster: |
| // http://normanmaurer.me/presentations/2014-facebook-eng-netty/slides.html#37.0 |
| b.channel(NioSocketChannel.class); |
| b.option(ChannelOption.SO_KEEPALIVE, true); |
| b.handler(new OnosCommunicationChannelInitializer()); |
| |
| // Start the client. |
| ChannelFuture f = b.connect(ep.host(), ep.port()).sync(); |
| return f.channel(); |
| } |
| |
| @Override |
| public void passivateObject(Endpoint ep, Channel channel) |
| throws Exception { |
| } |
| |
| @Override |
| public boolean validateObject(Endpoint ep, Channel channel) { |
| return channel.isOpen(); |
| } |
| } |
| |
| private class OnosCommunicationChannelInitializer extends ChannelInitializer<SocketChannel> { |
| |
| @Override |
| protected void initChannel(SocketChannel channel) throws Exception { |
| channel.pipeline() |
| .addLast(new MessageEncoder(serializer)) |
| .addLast(new MessageDecoder(NettyMessagingService.this, serializer)) |
| .addLast(new NettyMessagingService.InboundMessageDispatcher()); |
| } |
| } |
| |
| private class WriteTask implements Runnable { |
| |
| private final Object message; |
| private final Channel channel; |
| |
| public WriteTask(Channel channel, Object message) { |
| this.message = message; |
| this.channel = channel; |
| } |
| |
| @Override |
| public void run() { |
| channel.writeAndFlush(message); |
| } |
| } |
| |
| private class InboundMessageDispatcher extends SimpleChannelInboundHandler<InternalMessage> { |
| |
| @Override |
| protected void channelRead0(ChannelHandlerContext ctx, InternalMessage message) throws Exception { |
| String type = message.type(); |
| if (type.equals(InternalMessage.REPLY_MESSAGE_TYPE)) { |
| try { |
| AsyncResponse<?> futureResponse = |
| NettyMessagingService.this.responseFutures.getIfPresent(message.id()); |
| if (futureResponse != null) { |
| futureResponse.setResponse(message.payload()); |
| } |
| log.warn("Received a reply. But was unable to locate the request handle"); |
| } finally { |
| NettyMessagingService.this.responseFutures.invalidate(message.id()); |
| } |
| return; |
| } |
| MessageHandler handler = NettyMessagingService.this.getMessageHandler(type); |
| handler.handle(message); |
| } |
| } |
| } |