/**
* Copyright (C) 2010-2013 Alibaba Group Holding Limited
*
* Licensed 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 com.alibaba.rocketmq.remoting.netty;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelDuplexHandler;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPromise;
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.NioSocketChannel;
import io.netty.handler.timeout.IdleState;
import io.netty.handler.timeout.IdleStateEvent;
import io.netty.handler.timeout.IdleStateHandler;
import io.netty.util.concurrent.DefaultEventExecutorGroup;
import java.net.SocketAddress;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import java.util.Timer;
import java.util.TimerTask;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.alibaba.rocketmq.remoting.ChannelEventListener;
import com.alibaba.rocketmq.remoting.InvokeCallback;
import com.alibaba.rocketmq.remoting.RPCHook;
import com.alibaba.rocketmq.remoting.RemotingClient;
import com.alibaba.rocketmq.remoting.common.Pair;
import com.alibaba.rocketmq.remoting.common.RemotingHelper;
import com.alibaba.rocketmq.remoting.common.RemotingUtil;
import com.alibaba.rocketmq.remoting.exception.RemotingConnectException;
import com.alibaba.rocketmq.remoting.exception.RemotingSendRequestException;
import com.alibaba.rocketmq.remoting.exception.RemotingTimeoutException;
import com.alibaba.rocketmq.remoting.exception.RemotingTooMuchRequestException;
import com.alibaba.rocketmq.remoting.protocol.RemotingCommand;
/**
* Remoting客户端实现
*
* @author shijia.wxr<vintage.wang@gmail.com>
* @since 2013-7-13
*/
public class NettyRemotingClient extends NettyRemotingAbstract implements RemotingClient {
private static final Logger log = LoggerFactory.getLogger(RemotingHelper.RemotingLogName);
private static final long LockTimeoutMillis = 3000;
private final NettyClientConfig nettyClientConfig;
private final Bootstrap bootstrap = new Bootstrap();
private final EventLoopGroup eventLoopGroupWorker;
private DefaultEventExecutorGroup defaultEventExecutorGroup;
private final Lock lockChannelTables = new ReentrantLock();
private final ConcurrentHashMap<String /* addr */, ChannelWrapper> channelTables =
new ConcurrentHashMap<String, ChannelWrapper>();
// 定时器
private final Timer timer = new Timer("ClientHouseKeepingService", true);
// Name server相关
private final AtomicReference<List<String>> namesrvAddrList = new AtomicReference<List<String>>();
private final AtomicReference<String> namesrvAddrChoosed = new AtomicReference<String>();
private final AtomicInteger namesrvIndex = new AtomicInteger(initValueIndex());
private final Lock lockNamesrvChannel = new ReentrantLock();
// 处理Callback应答器
private final ExecutorService publicExecutor;
private final ChannelEventListener channelEventListener;
private RPCHook rpcHook;
class ChannelWrapper {
private final ChannelFuture channelFuture;
public ChannelWrapper(ChannelFuture channelFuture) {
this.channelFuture = channelFuture;
}
public boolean isOK() {
return (this.channelFuture.channel() != null && this.channelFuture.channel().isActive());
}
private Channel getChannel() {
return this.channelFuture.channel();
}
public ChannelFuture getChannelFuture() {
return channelFuture;
}
}
class NettyClientHandler extends SimpleChannelInboundHandler<RemotingCommand> {
@Override
protected void channelRead0(ChannelHandlerContext ctx, RemotingCommand msg) throws Exception {
processMessageReceived(ctx, msg);
}
}
class NettyConnetManageHandler extends ChannelDuplexHandler {
@Override
public void connect(ChannelHandlerContext ctx, SocketAddress remoteAddress,
SocketAddress localAddress, ChannelPromise promise) throws Exception {
final String local = localAddress == null ? "UNKNOW" : localAddress.toString();
final String remote = remoteAddress == null ? "UNKNOW" : remoteAddress.toString();
log.info("NETTY CLIENT PIPELINE: CONNECT {} => {}", local, remote);
super.connect(ctx, remoteAddress, localAddress, promise);
if (NettyRemotingClient.this.channelEventListener != null) {
NettyRemotingClient.this.putNettyEvent(new NettyEvent(NettyEventType.CONNECT, remoteAddress
.toString(), ctx.channel()));
}
}
@Override
public void disconnect(ChannelHandlerContext ctx, ChannelPromise promise) throws Exception {
final String remoteAddress = RemotingHelper.parseChannelRemoteAddr(ctx.channel());
log.info("NETTY CLIENT PIPELINE: DISCONNECT {}", remoteAddress);
closeChannel(ctx.channel());
super.disconnect(ctx, promise);
if (NettyRemotingClient.this.channelEventListener != null) {
NettyRemotingClient.this.putNettyEvent(new NettyEvent(NettyEventType.CLOSE, remoteAddress
.toString(), ctx.channel()));
}
}
@Override
public void close(ChannelHandlerContext ctx, ChannelPromise promise) throws Exception {
final String remoteAddress = RemotingHelper.parseChannelRemoteAddr(ctx.channel());
log.info("NETTY CLIENT PIPELINE: CLOSE {}", remoteAddress);
closeChannel(ctx.channel());
super.close(ctx, promise);
if (NettyRemotingClient.this.channelEventListener != null) {
NettyRemotingClient.this.putNettyEvent(new NettyEvent(NettyEventType.CLOSE, remoteAddress
.toString(), ctx.channel()));
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
final String remoteAddress = RemotingHelper.parseChannelRemoteAddr(ctx.channel());
log.warn("NETTY CLIENT PIPELINE: exceptionCaught {}", remoteAddress);
log.warn("NETTY CLIENT PIPELINE: exceptionCaught exception.", cause);
closeChannel(ctx.channel());
if (NettyRemotingClient.this.channelEventListener != null) {
NettyRemotingClient.this.putNettyEvent(new NettyEvent(NettyEventType.EXCEPTION, remoteAddress
.toString(), ctx.channel()));
}
}
@Override
public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
if (evt instanceof IdleStateEvent) {
IdleStateEvent evnet = (IdleStateEvent) evt;
if (evnet.state().equals(IdleState.ALL_IDLE)) {
final String remoteAddress = RemotingHelper.parseChannelRemoteAddr(ctx.channel());
log.warn("NETTY CLIENT PIPELINE: IDLE exception [{}]", remoteAddress);
closeChannel(ctx.channel());
if (NettyRemotingClient.this.channelEventListener != null) {
NettyRemotingClient.this.putNettyEvent(new NettyEvent(NettyEventType.IDLE,
remoteAddress.toString(), ctx.channel()));
}
}
}
ctx.fireUserEventTriggered(evt);
}
}
private static int initValueIndex() {
Random r = new Random();
return Math.abs(r.nextInt() % 999) % 999;
}
public NettyRemotingClient(final NettyClientConfig nettyClientConfig) {
this(nettyClientConfig, null);
}
public NettyRemotingClient(final NettyClientConfig nettyClientConfig,//
final ChannelEventListener channelEventListener) {
super(nettyClientConfig.getClientOnewaySemaphoreValue(), nettyClientConfig
.getClientAsyncSemaphoreValue());
this.nettyClientConfig = nettyClientConfig;
this.channelEventListener = channelEventListener;
int publicThreadNums = nettyClientConfig.getClientCallbackExecutorThreads();
if (publicThreadNums <= 0) {
publicThreadNums = 4;
}
this.publicExecutor = Executors.newFixedThreadPool(publicThreadNums, new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "NettyClientPublicExecutor_" + this.threadIndex.incrementAndGet());
}
});
this.eventLoopGroupWorker = new NioEventLoopGroup(1, new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, String.format("NettyClientSelector_%d",
this.threadIndex.incrementAndGet()));
}
});
}
@Override
public void start() {
this.defaultEventExecutorGroup = new DefaultEventExecutorGroup(//
nettyClientConfig.getClientWorkerThreads(), //
new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "NettyClientWorkerThread_" + this.threadIndex.incrementAndGet());
}
});
Bootstrap handler = this.bootstrap.group(this.eventLoopGroupWorker).channel(NioSocketChannel.class)//
//
.option(ChannelOption.TCP_NODELAY, true)
//
.option(ChannelOption.SO_KEEPALIVE, false)
//
.option(ChannelOption.SO_SNDBUF, nettyClientConfig.getClientSocketSndBufSize())
//
.option(ChannelOption.SO_RCVBUF, nettyClientConfig.getClientSocketRcvBufSize())
//
.handler(new ChannelInitializer<SocketChannel>() {
@Override
public void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast(//
defaultEventExecutorGroup, //
new NettyEncoder(), //
new NettyDecoder(), //
new IdleStateHandler(0, 0, nettyClientConfig.getClientChannelMaxIdleTimeSeconds()),//
new NettyConnetManageHandler(), //
new NettyClientHandler());
}
});
// 每隔1秒扫描下异步调用超时情况
this.timer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
try {
NettyRemotingClient.this.scanResponseTable();
}
catch (Exception e) {
log.error("scanResponseTable exception", e);
}
}
}, 1000 * 3, 1000);
if (this.channelEventListener != null) {
this.nettyEventExecuter.start();
}
}
@Override
public void shutdown() {
try {
this.timer.cancel();
for (ChannelWrapper cw : this.channelTables.values()) {
this.closeChannel(null, cw.getChannel());
}
this.channelTables.clear();
this.eventLoopGroupWorker.shutdownGracefully();
if (this.nettyEventExecuter != null) {
this.nettyEventExecuter.shutdown();
}
if (this.defaultEventExecutorGroup != null) {
this.defaultEventExecutorGroup.shutdownGracefully();
}
}
catch (Exception e) {
log.error("NettyRemotingClient shutdown exception, ", e);
}
if (this.publicExecutor != null) {
try {
this.publicExecutor.shutdown();
}
catch (Exception e) {
log.error("NettyRemotingServer shutdown exception, ", e);
}
}
}
private Channel getAndCreateChannel(final String addr) throws InterruptedException {
if (null == addr)
return getAndCreateNameserverChannel();
ChannelWrapper cw = this.channelTables.get(addr);
if (cw != null && cw.isOK()) {
return cw.getChannel();
}
return this.createChannel(addr);
}
private Channel getAndCreateNameserverChannel() throws InterruptedException {
String addr = this.namesrvAddrChoosed.get();
if (addr != null) {
ChannelWrapper cw = this.channelTables.get(addr);
if (cw != null && cw.isOK()) {
return cw.getChannel();
}
}
final List<String> addrList = this.namesrvAddrList.get();
// 加锁，尝试创建连接
if (this.lockNamesrvChannel.tryLock(LockTimeoutMillis, TimeUnit.MILLISECONDS)) {
try {
addr = this.namesrvAddrChoosed.get();
if (addr != null) {
ChannelWrapper cw = this.channelTables.get(addr);
if (cw != null && cw.isOK()) {
return cw.getChannel();
}
}
if (addrList != null && !addrList.isEmpty()) {
for (int i = 0; i < addrList.size(); i++) {
int index = this.namesrvIndex.incrementAndGet();
index = Math.abs(index);
index = index % addrList.size();
String newAddr = addrList.get(index);
this.namesrvAddrChoosed.set(newAddr);
Channel channelNew = this.createChannel(newAddr);
if (channelNew != null)
return channelNew;
}
}
}
catch (Exception e) {
log.error("getAndCreateNameserverChannel: create name server channel exception", e);
}
finally {
this.lockNamesrvChannel.unlock();
}
}
else {
log.warn("getAndCreateNameserverChannel: try to lock name server, but timeout, {}ms",
LockTimeoutMillis);
}
return null;
}
private Channel createChannel(final String addr) throws InterruptedException {
ChannelWrapper cw = this.channelTables.get(addr);
if (cw != null && cw.isOK()) {
return cw.getChannel();
}
// 进入临界区后，不能有阻塞操作，网络连接采用异步方式
if (this.lockChannelTables.tryLock(LockTimeoutMillis, TimeUnit.MILLISECONDS)) {
try {
boolean createNewConnection = false;
cw = this.channelTables.get(addr);
if (cw != null) {
// channel正常
if (cw.isOK()) {
return cw.getChannel();
}
// 正在连接，退出锁等待
else if (!cw.getChannelFuture().isDone()) {
createNewConnection = false;
}
// 说明连接不成功
else {
this.channelTables.remove(addr);
createNewConnection = true;
}
}
// ChannelWrapper不存在
else {
createNewConnection = true;
}
if (createNewConnection) {
ChannelFuture channelFuture =
this.bootstrap.connect(RemotingHelper.string2SocketAddress(addr));
log.info("createChannel: begin to connect remote host[{}] asynchronously", addr);
cw = new ChannelWrapper(channelFuture);
this.channelTables.put(addr, cw);
}
}
catch (Exception e) {
log.error("createChannel: create channel exception", e);
}
finally {
this.lockChannelTables.unlock();
}
}
else {
log.warn("createChannel: try to lock channel table, but timeout, {}ms", LockTimeoutMillis);
}
if (cw != null) {
ChannelFuture channelFuture = cw.getChannelFuture();
if (channelFuture.awaitUninterruptibly(this.nettyClientConfig.getConnectTimeoutMillis())) {
if (cw.isOK()) {
log.info("createChannel: connect remote host[{}] success, {}", addr,
channelFuture.toString());
return cw.getChannel();
}
else {
log.warn(
"createChannel: connect remote host[" + addr + "] failed, "
+ channelFuture.toString(), channelFuture.cause());
}
}
else {
log.warn("createChannel: connect remote host[{}] timeout {}ms, {}", addr,
this.nettyClientConfig.getConnectTimeoutMillis(), channelFuture.toString());
}
}
return null;
}
public void closeChannel(final String addr, final Channel channel) {
if (null == channel)
return;
final String addrRemote = null == addr ? RemotingHelper.parseChannelRemoteAddr(channel) : addr;
try {
if (this.lockChannelTables.tryLock(LockTimeoutMillis, TimeUnit.MILLISECONDS)) {
try {
boolean removeItemFromTable = true;
final ChannelWrapper prevCW = this.channelTables.get(addrRemote);
log.info("closeChannel: begin close the channel[{}] Found: {}", addrRemote,
(prevCW != null));
if (null == prevCW) {
log.info(
"closeChannel: the channel[{}] has been removed from the channel table before",
addrRemote);
removeItemFromTable = false;
}
else if (prevCW.getChannel() != channel) {
log.info(
"closeChannel: the channel[{}] has been closed before, and has been created again, nothing to do.",
addrRemote);
removeItemFromTable = false;
}
if (removeItemFromTable) {
this.channelTables.remove(addrRemote);
log.info("closeChannel: the channel[{}] was removed from channel table", addrRemote);
}
RemotingUtil.closeChannel(channel);
}
catch (Exception e) {
log.error("closeChannel: close the channel exception", e);
}
finally {
this.lockChannelTables.unlock();
}
}
else {
log.warn("closeChannel: try to lock channel table, but timeout, {}ms", LockTimeoutMillis);
}
}
catch (InterruptedException e) {
log.error("closeChannel exception", e);
}
}
public void closeChannel(final Channel channel) {
if (null == channel)
return;
try {
if (this.lockChannelTables.tryLock(LockTimeoutMillis, TimeUnit.MILLISECONDS)) {
try {
boolean removeItemFromTable = true;
ChannelWrapper prevCW = null;
String addrRemote = null;
for (String key : channelTables.keySet()) {
ChannelWrapper prev = this.channelTables.get(key);
if (prev.getChannel() != null) {
if (prev.getChannel() == channel) {
prevCW = prev;
addrRemote = key;
break;
}
}
}
if (null == prevCW) {
log.info(
"eventCloseChannel: the channel[{}] has been removed from the channel table before",
addrRemote);
removeItemFromTable = false;
}
if (removeItemFromTable) {
this.channelTables.remove(addrRemote);
log.info("closeChannel: the channel[{}] was removed from channel table", addrRemote);
RemotingUtil.closeChannel(channel);
}
}
catch (Exception e) {
log.error("closeChannel: close the channel exception", e);
}
finally {
this.lockChannelTables.unlock();
}
}
else {
log.warn("closeChannel: try to lock channel table, but timeout, {}ms", LockTimeoutMillis);
}
}
catch (InterruptedException e) {
log.error("closeChannel exception", e);
}
}
@Override
public void registerProcessor(int requestCode, NettyRequestProcessor processor, ExecutorService executor) {
ExecutorService executorThis = executor;
if (null == executor) {
executorThis = this.publicExecutor;
}
Pair<NettyRequestProcessor, ExecutorService> pair =
new Pair<NettyRequestProcessor, ExecutorService>(processor, executorThis);
this.processorTable.put(requestCode, pair);
}
@Override
public RemotingCommand invokeSync(String addr, final RemotingCommand request, long timeoutMillis)
throws InterruptedException, RemotingConnectException, RemotingSendRequestException,
RemotingTimeoutException {
final Channel channel = this.getAndCreateChannel(addr);
if (channel != null && channel.isActive()) {
try {
if (this.rpcHook != null) {
this.rpcHook.doBeforeRequest(addr, request);
}
RemotingCommand response = this.invokeSyncImpl(channel, request, timeoutMillis);
if (this.rpcHook != null) {
this.rpcHook.doAfterResponse(request, response);
}
return response;
}
catch (RemotingSendRequestException e) {
log.warn("invokeSync: send request exception, so close the channel[{}]", addr);
this.closeChannel(addr, channel);
throw e;
}
catch (RemotingTimeoutException e) {
log.warn("invokeSync: wait response timeout exception, the channel[{}]", addr);
// 超时异常如果关闭连接可能会产生连锁反应
// this.closeChannel(addr, channel);
throw e;
}
}
else {
this.closeChannel(addr, channel);
throw new RemotingConnectException(addr);
}
}
@Override
public void invokeAsync(String addr, RemotingCommand request, long timeoutMillis,
InvokeCallback invokeCallback) throws InterruptedException, RemotingConnectException,
RemotingTooMuchRequestException, RemotingTimeoutException, RemotingSendRequestException {
final Channel channel = this.getAndCreateChannel(addr);
if (channel != null && channel.isActive()) {
try {
if (this.rpcHook != null) {
this.rpcHook.doBeforeRequest(addr, request);
}
this.invokeAsyncImpl(channel, request, timeoutMillis, invokeCallback);
}
catch (RemotingSendRequestException e) {
log.warn("invokeAsync: send request exception, so close the channel[{}]", addr);
this.closeChannel(addr, channel);
throw e;
}
}
else {
this.closeChannel(addr, channel);
throw new RemotingConnectException(addr);
}
}
@Override
public void invokeOneway(String addr, RemotingCommand request, long timeoutMillis)
throws InterruptedException, RemotingConnectException, RemotingTooMuchRequestException,
RemotingTimeoutException, RemotingSendRequestException {
final Channel channel = this.getAndCreateChannel(addr);
if (channel != null && channel.isActive()) {
try {
if (this.rpcHook != null) {
this.rpcHook.doBeforeRequest(addr, request);
}
this.invokeOnewayImpl(channel, request, timeoutMillis);
}
catch (RemotingSendRequestException e) {
log.warn("invokeOneway: send request exception, so close the channel[{}]", addr);
this.closeChannel(addr, channel);
throw e;
}
}
else {
this.closeChannel(addr, channel);
throw new RemotingConnectException(addr);
}
}
@Override
public ExecutorService getCallbackExecutor() {
return this.publicExecutor;
}
@Override
public void updateNameServerAddressList(List<String> addrs) {
List<String> old = this.namesrvAddrList.get();
boolean update = false;
if (!addrs.isEmpty()) {
if (null == old) {
update = true;
}
else if (addrs.size() != old.size()) {
update = true;
}
else {
for (int i = 0; i < addrs.size() && !update; i++) {
if (!old.contains(addrs.get(i))) {
update = true;
}
}
}
if (update) {
Collections.shuffle(addrs);
this.namesrvAddrList.set(addrs);
}
}
}
@Override
public ChannelEventListener getChannelEventListener() {
return channelEventListener;
}
public List<String> getNamesrvAddrList() {
return namesrvAddrList.get();
}
@Override
public List<String> getNameServerAddressList() {
return this.namesrvAddrList.get();
}
public RPCHook getRpcHook() {
return rpcHook;
}
@Override
public void registerRPCHook(RPCHook rpcHook) {
this.rpcHook = rpcHook;
}
@Override
public RPCHook getRPCHook() {
return this.rpcHook;
}
}