Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame^] | 1 | package org.onlab.netty; |
| 2 | |
| 3 | import java.io.IOException; |
| 4 | import java.net.UnknownHostException; |
| 5 | import java.util.concurrent.ConcurrentHashMap; |
| 6 | import java.util.concurrent.ConcurrentMap; |
| 7 | import java.util.concurrent.TimeUnit; |
| 8 | |
| 9 | import io.netty.bootstrap.Bootstrap; |
| 10 | import io.netty.bootstrap.ServerBootstrap; |
| 11 | import io.netty.buffer.PooledByteBufAllocator; |
| 12 | import io.netty.channel.Channel; |
| 13 | import io.netty.channel.ChannelFuture; |
| 14 | import io.netty.channel.ChannelHandlerContext; |
| 15 | import io.netty.channel.ChannelInitializer; |
| 16 | import io.netty.channel.ChannelOption; |
| 17 | import io.netty.channel.EventLoopGroup; |
| 18 | import io.netty.channel.SimpleChannelInboundHandler; |
| 19 | import io.netty.channel.nio.NioEventLoopGroup; |
| 20 | import io.netty.channel.socket.SocketChannel; |
| 21 | import io.netty.channel.socket.nio.NioServerSocketChannel; |
| 22 | import io.netty.channel.socket.nio.NioSocketChannel; |
| 23 | |
| 24 | import org.apache.commons.lang.math.RandomUtils; |
| 25 | import org.apache.commons.pool.KeyedObjectPool; |
| 26 | import org.apache.commons.pool.KeyedPoolableObjectFactory; |
| 27 | import org.apache.commons.pool.impl.GenericKeyedObjectPool; |
| 28 | import org.slf4j.Logger; |
| 29 | import org.slf4j.LoggerFactory; |
| 30 | |
| 31 | import com.google.common.cache.Cache; |
| 32 | import com.google.common.cache.CacheBuilder; |
| 33 | |
| 34 | /** |
| 35 | * A Netty based implementation of MessagingService. |
| 36 | */ |
| 37 | public class NettyMessagingService implements MessagingService { |
| 38 | |
| 39 | private final Logger log = LoggerFactory.getLogger(getClass()); |
| 40 | |
| 41 | private KeyedObjectPool<Endpoint, Channel> channels = |
| 42 | new GenericKeyedObjectPool<Endpoint, Channel>(new OnosCommunicationChannelFactory()); |
| 43 | private final int port; |
| 44 | private final EventLoopGroup bossGroup = new NioEventLoopGroup(); |
| 45 | private final EventLoopGroup workerGroup = new NioEventLoopGroup(); |
| 46 | private final ConcurrentMap<String, MessageHandler> handlers = new ConcurrentHashMap<>(); |
| 47 | private Cache<Long, AsyncResponse<?>> responseFutures; |
| 48 | private final Endpoint localEp; |
| 49 | |
| 50 | protected Serializer serializer; |
| 51 | |
| 52 | public NettyMessagingService() { |
| 53 | // TODO: Default port should be configurable. |
| 54 | this(8080); |
| 55 | } |
| 56 | |
| 57 | // FIXME: Constructor should not throw exceptions. |
| 58 | public NettyMessagingService(int port) { |
| 59 | this.port = port; |
| 60 | try { |
| 61 | localEp = new Endpoint(java.net.InetAddress.getLocalHost().getHostName(), port); |
| 62 | } catch (UnknownHostException e) { |
| 63 | // bailing out. |
| 64 | throw new RuntimeException(e); |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | public void activate() throws Exception { |
| 69 | responseFutures = CacheBuilder.newBuilder() |
| 70 | .maximumSize(100000) |
| 71 | .weakValues() |
| 72 | // TODO: Once the entry expires, notify blocking threads (if any). |
| 73 | .expireAfterWrite(10, TimeUnit.MINUTES) |
| 74 | .build(); |
| 75 | startAcceptingConnections(); |
| 76 | } |
| 77 | |
| 78 | public void deactivate() throws Exception { |
| 79 | channels.close(); |
| 80 | bossGroup.shutdownGracefully(); |
| 81 | workerGroup.shutdownGracefully(); |
| 82 | } |
| 83 | |
| 84 | @Override |
| 85 | public void sendAsync(Endpoint ep, String type, Object payload) throws IOException { |
| 86 | InternalMessage message = new InternalMessage.Builder(this) |
| 87 | .withId(RandomUtils.nextLong()) |
| 88 | .withSender(localEp) |
| 89 | .withType(type) |
| 90 | .withPayload(payload) |
| 91 | .build(); |
| 92 | sendAsync(ep, message); |
| 93 | } |
| 94 | |
| 95 | protected void sendAsync(Endpoint ep, InternalMessage message) throws IOException { |
| 96 | Channel channel = null; |
| 97 | try { |
| 98 | channel = channels.borrowObject(ep); |
| 99 | channel.eventLoop().execute(new WriteTask(channel, message)); |
| 100 | } catch (Exception e) { |
| 101 | throw new IOException(e); |
| 102 | } finally { |
| 103 | try { |
| 104 | channels.returnObject(ep, channel); |
| 105 | } catch (Exception e) { |
| 106 | log.warn("Error returning object back to the pool", e); |
| 107 | // ignored. |
| 108 | } |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | @Override |
| 113 | public <T> Response<T> sendAndReceive(Endpoint ep, String type, Object payload) |
| 114 | throws IOException { |
| 115 | AsyncResponse<T> futureResponse = new AsyncResponse<T>(); |
| 116 | Long messageId = RandomUtils.nextLong(); |
| 117 | responseFutures.put(messageId, futureResponse); |
| 118 | InternalMessage message = new InternalMessage.Builder(this) |
| 119 | .withId(messageId) |
| 120 | .withSender(localEp) |
| 121 | .withType(type) |
| 122 | .withPayload(payload) |
| 123 | .build(); |
| 124 | sendAsync(ep, message); |
| 125 | return futureResponse; |
| 126 | } |
| 127 | |
| 128 | @Override |
| 129 | public void registerHandler(String type, MessageHandler handler) { |
| 130 | // TODO: Is this the right semantics for handler registration? |
| 131 | handlers.putIfAbsent(type, handler); |
| 132 | } |
| 133 | |
| 134 | public void unregisterHandler(String type) { |
| 135 | handlers.remove(type); |
| 136 | } |
| 137 | |
| 138 | private MessageHandler getMessageHandler(String type) { |
| 139 | return handlers.get(type); |
| 140 | } |
| 141 | |
| 142 | private void startAcceptingConnections() throws InterruptedException { |
| 143 | ServerBootstrap b = new ServerBootstrap(); |
| 144 | b.option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT); |
| 145 | b.group(bossGroup, workerGroup) |
| 146 | .channel(NioServerSocketChannel.class) |
| 147 | .childHandler(new OnosCommunicationChannelInitializer()) |
| 148 | .option(ChannelOption.SO_BACKLOG, 128) |
| 149 | .childOption(ChannelOption.SO_KEEPALIVE, true); |
| 150 | |
| 151 | // Bind and start to accept incoming connections. |
| 152 | b.bind(port).sync(); |
| 153 | } |
| 154 | |
| 155 | private class OnosCommunicationChannelFactory |
| 156 | implements KeyedPoolableObjectFactory<Endpoint, Channel> { |
| 157 | |
| 158 | @Override |
| 159 | public void activateObject(Endpoint endpoint, Channel channel) |
| 160 | throws Exception { |
| 161 | } |
| 162 | |
| 163 | @Override |
| 164 | public void destroyObject(Endpoint ep, Channel channel) throws Exception { |
| 165 | channel.close(); |
| 166 | } |
| 167 | |
| 168 | @Override |
| 169 | public Channel makeObject(Endpoint ep) throws Exception { |
| 170 | Bootstrap b = new Bootstrap(); |
| 171 | b.option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT); |
| 172 | b.group(workerGroup); |
| 173 | // TODO: Make this faster: |
| 174 | // http://normanmaurer.me/presentations/2014-facebook-eng-netty/slides.html#37.0 |
| 175 | b.channel(NioSocketChannel.class); |
| 176 | b.option(ChannelOption.SO_KEEPALIVE, true); |
| 177 | b.handler(new OnosCommunicationChannelInitializer()); |
| 178 | |
| 179 | // Start the client. |
| 180 | ChannelFuture f = b.connect(ep.host(), ep.port()).sync(); |
| 181 | return f.channel(); |
| 182 | } |
| 183 | |
| 184 | @Override |
| 185 | public void passivateObject(Endpoint ep, Channel channel) |
| 186 | throws Exception { |
| 187 | } |
| 188 | |
| 189 | @Override |
| 190 | public boolean validateObject(Endpoint ep, Channel channel) { |
| 191 | return channel.isOpen(); |
| 192 | } |
| 193 | } |
| 194 | |
| 195 | private class OnosCommunicationChannelInitializer extends ChannelInitializer<SocketChannel> { |
| 196 | |
| 197 | @Override |
| 198 | protected void initChannel(SocketChannel channel) throws Exception { |
| 199 | channel.pipeline() |
| 200 | .addLast(new MessageEncoder(serializer)) |
| 201 | .addLast(new MessageDecoder(NettyMessagingService.this, serializer)) |
| 202 | .addLast(new NettyMessagingService.InboundMessageDispatcher()); |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | private class WriteTask implements Runnable { |
| 207 | |
| 208 | private final Object message; |
| 209 | private final Channel channel; |
| 210 | |
| 211 | public WriteTask(Channel channel, Object message) { |
| 212 | this.message = message; |
| 213 | this.channel = channel; |
| 214 | } |
| 215 | |
| 216 | @Override |
| 217 | public void run() { |
| 218 | channel.writeAndFlush(message); |
| 219 | } |
| 220 | } |
| 221 | |
| 222 | private class InboundMessageDispatcher extends SimpleChannelInboundHandler<InternalMessage> { |
| 223 | |
| 224 | @Override |
| 225 | protected void channelRead0(ChannelHandlerContext ctx, InternalMessage message) throws Exception { |
| 226 | String type = message.type(); |
| 227 | if (type.equals(InternalMessage.REPLY_MESSAGE_TYPE)) { |
| 228 | try { |
| 229 | AsyncResponse<?> futureResponse = |
| 230 | NettyMessagingService.this.responseFutures.getIfPresent(message.id()); |
| 231 | if (futureResponse != null) { |
| 232 | futureResponse.setResponse(message.payload()); |
| 233 | } |
| 234 | log.warn("Received a reply. But was unable to locate the request handle"); |
| 235 | } finally { |
| 236 | NettyMessagingService.this.responseFutures.invalidate(message.id()); |
| 237 | } |
| 238 | return; |
| 239 | } |
| 240 | MessageHandler handler = NettyMessagingService.this.getMessageHandler(type); |
| 241 | handler.handle(message); |
| 242 | } |
| 243 | } |
| 244 | } |