netty在rocket中的使用
client和server都是使用netty通信
client在创建BootStrap时的简化代码如下
// NettyRemotingClient
bootstrap.handler(new ChannelInitializer<SocketChannel>(){
public void initChannel(SocketChannel ch){
pipepline.addLast(new NettyClientHandler());
}
}
class NettyClientHandler extends SimpleChannelInboundHandler<RemotingCommand>{
void channelRead0(ChannelHandlerContext ctx, RemotingCommand msg){
processMessageReceived(ctx, msg);
}
}
在处理消息的时候进行request和response的判断
// NettyRemotingAbstract
public void processMessageReceived(ChannelHandlerContext ctx, RemotingCommand msg) throws Exception {
final RemotingCommand cmd = msg;
if (cmd != null) {
switch (cmd.getType()) {
case REQUEST_COMMAND:
processRequestCommand(ctx, cmd);
break;
case RESPONSE_COMMAND:
processResponseCommand(ctx, cmd);
break;
default:
break;
}
}
}
找到对应的processor处理request，注意这里扔进了线程池处理，如果是顺序性消息会根据key分成不同的批次，同一批消息由同一个线程处理。
// NettyRemotingAbstract
public void processRequestCommand(final ChannelHandlerContext ctx, final RemotingCommand cmd) {
final Pair<NettyRequestProcessor, ExecutorService> matched = this.processorTable.get(cmd.getCode());
final Pair<NettyRequestProcessor, ExecutorService> pair = null == matched ? this.defaultRequestProcessor : matched;
final int opaque = cmd.getOpaque();
if (pair != null) {
Runnable run = new Runnable() {
@Override
public void run() {
try {
doBeforeRpcHooks(RemotingHelper.parseChannelRemoteAddr(ctx.channel()), cmd);
final RemotingResponseCallback callback = new RemotingResponseCallback() {
@Override
public void callback(RemotingCommand response) {
doAfterRpcHooks(RemotingHelper.parseChannelRemoteAddr(ctx.channel()), cmd, response);
if (!cmd.isOnewayRPC()) {
if (response != null) {
response.setOpaque(opaque);
response.markResponseType();
try {
ctx.writeAndFlush(response);
} catch (Throwable e) {
log.error("process request over, but response failed", e);
log.error(cmd.toString());
log.error(response.toString());
}
} else {
}
}
}
};
if (pair.getObject1() instanceof AsyncNettyRequestProcessor) {
AsyncNettyRequestProcessor processor = (AsyncNettyRequestProcessor)pair.getObject1();
processor.asyncProcessRequest(ctx, cmd, callback);
} else {
NettyRequestProcessor processor = pair.getObject1();
RemotingCommand response = processor.processRequest(ctx, cmd);
callback.callback(response);
}
} catch (Throwable e) {
log.error("process request exception", e);
log.error(cmd.toString());
if (!cmd.isOnewayRPC()) {
final RemotingCommand response = RemotingCommand.createResponseCommand(RemotingSysResponseCode.SYSTEM_ERROR,
RemotingHelper.exceptionSimpleDesc(e));
response.setOpaque(opaque);
ctx.writeAndFlush(response);
}
}
}
};
if (pair.getObject1().rejectRequest()) {
final RemotingCommand response = RemotingCommand.createResponseCommand(RemotingSysResponseCode.SYSTEM_BUSY,
"[REJECTREQUEST]system busy, start flow control for a while");
response.setOpaque(opaque);
ctx.writeAndFlush(response);
return;
}
try {
final RequestTask requestTask = new RequestTask(run, ctx.channel(), cmd);
pair.getObject2().submit(requestTask);
} catch (RejectedExecutionException e) {
if ((System.currentTimeMillis() % 10000) == 0) {
log.warn(RemotingHelper.parseChannelRemoteAddr(ctx.channel())
+ ", too many requests and system thread pool busy, RejectedExecutionException "
+ pair.getObject2().toString()
+ " request code: " + cmd.getCode());
}
if (!cmd.isOnewayRPC()) {
final RemotingCommand response = RemotingCommand.createResponseCommand(RemotingSysResponseCode.SYSTEM_BUSY,
"[OVERLOAD]system busy, start flow control for a while");
response.setOpaque(opaque);
ctx.writeAndFlush(response);
}
}
} else {
String error = " request type " + cmd.getCode() + " not supported";
final RemotingCommand response =
RemotingCommand.createResponseCommand(RemotingSysResponseCode.REQUEST_CODE_NOT_SUPPORTED, error);
response.setOpaque(opaque);
ctx.writeAndFlush(response);
log.error(RemotingHelper.parseChannelRemoteAddr(ctx.channel()) + error);
}
}
一般是在ClientRemotingProcessor中处理
// ClientRemotingProcessor
public RemotingCommand processRequest(ChannelHandlerContext ctx,
RemotingCommand request) throws RemotingCommandException {
switch (request.getCode()) {
case RequestCode.CHECK_TRANSACTION_STATE:
return this.checkTransactionState(ctx, request);
case RequestCode.NOTIFY_CONSUMER_IDS_CHANGED:
return this.notifyConsumerIdsChanged(ctx, request);
case RequestCode.RESET_CONSUMER_CLIENT_OFFSET:
return this.resetOffset(ctx, request);
case RequestCode.GET_CONSUMER_STATUS_FROM_CLIENT:
return this.getConsumeStatus(ctx, request);
case RequestCode.GET_CONSUMER_RUNNING_INFO:
return this.getConsumerRunningInfo(ctx, request);
case RequestCode.CONSUME_MESSAGE_DIRECTLY:
return this.consumeMessageDirectly(ctx, request);
case RequestCode.PUSH_REPLY_MESSAGE_TO_CLIENT:
return this.receiveReplyMessage(ctx, request);
default:
break;
}
return null;
}
如果是Consumer，步骤如下，decodeMessage，找到对应的MQClientInstance，进行消费处理
// ClientRemotingProcessor
private RemotingCommand consumeMessageDirectly(ChannelHandlerContext ctx,
RemotingCommand request) throws RemotingCommandException {
final RemotingCommand response = RemotingCommand.createResponseCommand(null);
final ConsumeMessageDirectlyResultRequestHeader requestHeader =
(ConsumeMessageDirectlyResultRequestHeader) request
.decodeCommandCustomHeader(ConsumeMessageDirectlyResultRequestHeader.class);
final MessageExt msg = MessageDecoder.decode(ByteBuffer.wrap(request.getBody()));
ConsumeMessageDirectlyResult result =
this.mqClientFactory.consumeMessageDirectly(msg, requestHeader.getConsumerGroup(), requestHeader.getBrokerName());
if (null != result) {
response.setCode(ResponseCode.SUCCESS);
response.setBody(result.encode());
} else {
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark(String.format("The Consumer Group <%s> not exist in this consumer", requestHeader.getConsumerGroup()));
}
return response;
}
具体消费还是在MQClientInstance中，找到group对应的DefaultMQPushConsumerImpl，然后再找到对应的consumerService
// MQClientInstance
public ConsumeMessageDirectlyResult consumeMessageDirectly(final MessageExt msg,
final String consumerGroup,
final String brokerName) {
MQConsumerInner mqConsumerInner = this.consumerTable.get(consumerGroup);
if (null != mqConsumerInner) {
DefaultMQPushConsumerImpl consumer = (DefaultMQPushConsumerImpl) mqConsumerInner;
ConsumeMessageDirectlyResult result = consumer.getConsumeMessageService().consumeMessageDirectly(msg, brokerName);
return result;
}
return null;
}
假设使用的是普通的消息，会并发消费，对应是ConsumerMessageConcurrentlyService，在里面会使用代码中注册的MessageListener处理消息，若是处理失败，会标记消息，下次继续处理
@Override
public ConsumeMessageDirectlyResult consumeMessageDirectly(MessageExt msg, String brokerName) {
ConsumeMessageDirectlyResult result = new ConsumeMessageDirectlyResult();
result.setOrder(false);
result.setAutoCommit(true);
List<MessageExt> msgs = new ArrayList<MessageExt>();
msgs.add(msg);
MessageQueue mq = new MessageQueue();
mq.setBrokerName(brokerName);
mq.setTopic(msg.getTopic());
mq.setQueueId(msg.getQueueId());
ConsumeConcurrentlyContext context = new ConsumeConcurrentlyContext(mq);
this.defaultMQPushConsumerImpl.resetRetryAndNamespace(msgs, this.consumerGroup);
final long beginTime = System.currentTimeMillis();
log.info("consumeMessageDirectly receive new message: {}", msg);
try {
ConsumeConcurrentlyStatus status = this.messageListener.consumeMessage(msgs, context);
if (status != null) {
switch (status) {
case CONSUME_SUCCESS:
result.setConsumeResult(CMResult.CR_SUCCESS);
break;
case RECONSUME_LATER:
result.setConsumeResult(CMResult.CR_LATER);
break;
default:
break;
}
} else {
result.setConsumeResult(CMResult.CR_RETURN_NULL);
}
} catch (Throwable e) {
result.setConsumeResult(CMResult.CR_THROW_EXCEPTION);
result.setRemark(RemotingHelper.exceptionSimpleDesc(e));
log.warn(String.format("consumeMessageDirectly exception: %s Group: %s Msgs: %s MQ: %s",
RemotingHelper.exceptionSimpleDesc(e),
ConsumeMessageConcurrentlyService.this.consumerGroup,
msgs,
mq), e);
}
result.setSpentTimeMills(System.currentTimeMillis() - beginTime);
log.info("consumeMessageDirectly Result: {}", result);
return result;
}
Producer发送消息
producer.send(msg)
默认的是发送同步消息
根据message的topic找到对应的TopicInfo，如果broker中没有，将会生成TopicInfo，默认的queue数量为4，（定义在DefaultMQProducer中）发送消息时从队列数组中选择一个。
topic在client端和server端不同，client端的为TopicPublishInfo，server端的为TopicConfig。
客户端生成的topic默认的队列数量为4，服务端也就是broker中生成的topic会根据客户端提供的队列数量设定，但是最大为16。创建topic的代码在TopicConfigManager中。
根据message包装为RemotingCommand，默认使用netty传送数据。topic，queue等信息存放在了header中。
发送时定义了钩子函数，可以通过构造Producer时传入RPCHook来进行rpc时的控制。
通过channel.writeAndFlush发送cmd，并注册回调，在响应成功后返回，使用了CountDownLatch。
Consumer消费消息
subscribe
// DefaultMQPushConsumerImpl
public void subscribe(String topic, String subExpression) throws MQClientException {
try {
// 生成广播信息，对应的一个topic里面一个或者多个tag
SubscriptionData subscriptionData = FilterAPI.buildSubscriptionData(this.defaultMQPushConsumer.getConsumerGroup(),
topic, subExpression);
this.rebalanceImpl.getSubscriptionInner().put(topic, subscriptionData);
if (this.mQClientFactory != null) {
this.mQClientFactory.sendHeartbeatToAllBrokerWithLock();
}
} catch (Exception e) {
throw new MQClientException("subscription exception", e);
}
}
registerMessageListener
// DefaultMQPushConsumer
@Override
public void registerMessageListener(MessageListenerConcurrently messageListener) {
this.messageListener = messageListener;
this.defaultMQPushConsumerImpl.registerMessageListener(messageListener);
}
// DefaultMQPushConsumerImpl
public void registerMessageListener(MessageListener messageListener) {
this.messageListenerInner = messageListener;
}
start
// DefaultMQPushConsumerImpl
this.serviceState = ServiceState.START_FAILED;
this.checkConfig();
this.copySubscription();
if (this.defaultMQPushConsumer.getMessageModel() == MessageModel.CLUSTERING) {
this.defaultMQPushConsumer.changeInstanceNameToPID();
}
// 和Producer相同，创建MQClientInstance
this.mQClientFactory = MQClientManager.getInstance().getOrCreateMQClientInstance(this.defaultMQPushConsumer, this.rpcHook);
this.rebalanceImpl.setConsumerGroup(this.defaultMQPushConsumer.getConsumerGroup());
this.rebalanceImpl.setMessageModel(this.defaultMQPushConsumer.getMessageModel());
this.rebalanceImpl.setAllocateMessageQueueStrategy(this.defaultMQPushConsumer.getAllocateMessageQueueStrategy());
this.rebalanceImpl.setmQClientFactory(this.mQClientFactory);
this.pullAPIWrapper = new PullAPIWrapper(
mQClientFactory,
this.defaultMQPushConsumer.getConsumerGroup(), isUnitMode());
this.pullAPIWrapper.registerFilterMessageHook(filterMessageHookList);
if (this.defaultMQPushConsumer.getOffsetStore() != null) {
this.offsetStore = this.defaultMQPushConsumer.getOffsetStore();
} else {
switch (this.defaultMQPushConsumer.getMessageModel()) {
case BROADCASTING:
this.offsetStore = new LocalFileOffsetStore(this.mQClientFactory, this.defaultMQPushConsumer.getConsumerGroup());
break;
case CLUSTERING:
this.offsetStore = new RemoteBrokerOffsetStore(this.mQClientFactory, this.defaultMQPushConsumer.getConsumerGroup());
break;
default:
break;
}
this.defaultMQPushConsumer.setOffsetStore(this.offsetStore);
}
this.offsetStore.load();
if (this.getMessageListenerInner() instanceof MessageListenerOrderly) {
this.consumeOrderly = true;
this.consumeMessageService =
new ConsumeMessageOrderlyService(this, (MessageListenerOrderly) this.getMessageListenerInner());
} else if (this.getMessageListenerInner() instanceof MessageListenerConcurrently) {
this.consumeOrderly = false;
this.consumeMessageService =
new ConsumeMessageConcurrentlyService(this, (MessageListenerConcurrently) this.getMessageListenerInner());
}
this.consumeMessageService.start();
boolean registerOK = mQClientFactory.registerConsumer(this.defaultMQPushConsumer.getConsumerGroup(), this);
if (!registerOK) {
this.serviceState = ServiceState.CREATE_JUST;
this.consumeMessageService.shutdown(defaultMQPushConsumer.getAwaitTerminationMillisWhenShutdown());
throw new MQClientException("The consumer group[" + this.defaultMQPushConsumer.getConsumerGroup()
+ "] has been created before, specify another name please." + FAQUrl.suggestTodo(FAQUrl.GROUP_NAME_DUPLICATE_URL),
null);
}
mQClientFactory.start();
log.info("the consumer [{}] start OK.", this.defaultMQPushConsumer.getConsumerGroup());
this.serviceState = ServiceState.RUNNING;
private void copySubscription() throws MQClientException {
try {
Map<String, String> sub = this.defaultMQPushConsumer.getSubscription();
if (sub != null) {
for (final Map.Entry<String, String> entry : sub.entrySet()) {
final String topic = entry.getKey();
final String subString = entry.getValue();
SubscriptionData subscriptionData = FilterAPI.buildSubscriptionData(this.defaultMQPushConsumer.getConsumerGroup(),
topic, subString);
this.rebalanceImpl.getSubscriptionInner().put(topic, subscriptionData);
}
}
if (null == this.messageListenerInner) {
this.messageListenerInner = this.defaultMQPushConsumer.getMessageListener();
}
// 默认是CLUSTERING，即集群模式
switch (this.defaultMQPushConsumer.getMessageModel()) {
case BROADCASTING:
break;
case CLUSTERING:
final String retryTopic = MixAll.getRetryTopic(this.defaultMQPushConsumer.getConsumerGroup());
SubscriptionData subscriptionData = FilterAPI.buildSubscriptionData(this.defaultMQPushConsumer.getConsumerGroup(),
retryTopic, SubscriptionData.SUB_ALL);
this.rebalanceImpl.getSubscriptionInner().put(retryTopic, subscriptionData);
break;
default:
break;
}
} catch (Exception e) {
throw new MQClientException("subscription exception", e);
}
}
使用DefaultMQPushConsumer时，看起来是push模式，其实是对pull的封装。
两个重要的service类：RebalanceService，PullMessageService。RebalanceService是在客户端做负载均衡，找到一个topic对应的MessageQueue，构造request，由PullMessageService处理request，给broker发送请求，返回消息。PullMessageService是使用while不停的处理队列中的request的。
两个Service之间的沟通是通过LinkedBlockQueue，RebalanceService将request放入阻塞队列，PullMessageService从阻塞队列获取request进行处理。若是当前查询没有数据，会将request重新放入阻塞队列，下次继续处理。若是获取到了数据，会根据PullInterval来判断，如果大于0，会放入延迟线程池，在指定的毫秒后继续放入阻塞队列。默认为0，会立即将该request继续放入阻塞队列中。（代码在DefaultMQPushConsumerImpl）
客户端负载均衡。由于会定时去nameserver获取topic的信息，因此在客户端有topic和broker以及MessageQueue的映射。
producer和consumer定时检查TopicRoute
topic是和broker对应的，一个topic会存放在一个或者多个broker中，对应关系存放在nameserver。producer和consumer会通过和nameserver通信来找到topic对应的broker。broker可能会发生变化，因此在客户端会定时检查broker的信息。
在MQClientInstance启动时会启动一些定时任务
// MQClientInstance
public void start() throws MQClientException {
synchronized (this) {
switch (this.serviceState) {
case CREATE_JUST:
this.serviceState = ServiceState.START_FAILED;
// If not specified,looking address from name server
if (null == this.clientConfig.getNamesrvAddr()) {
this.mQClientAPIImpl.fetchNameServerAddr();
}
// Start request-response channel
this.mQClientAPIImpl.start();
// Start various schedule tasks
this.startScheduledTask();
// Start pull service
this.pullMessageService.start();
// Start rebalance service
this.rebalanceService.start();
// Start push service
this.defaultMQProducer.getDefaultMQProducerImpl().start(false);
...
查看定时任务方法startScheduledTask
// MQClientInstance
private void startScheduledTask() {
...
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
MQClientInstance.this.updateTopicRouteInfoFromNameServer();
} catch (Exception e) {
log.error("ScheduledTask updateTopicRouteInfoFromNameServer exception", e);
}
}
}, 10, this.clientConfig.getPollNameServerInterval(), TimeUnit.MILLISECONDS);
...
里面对于Producer和Consumer都进行了处理
public void updateTopicRouteInfoFromNameServer() {
Set<String> topicList = new HashSet<String>();
// Consumer
{
Iterator<Entry<String, MQConsumerInner>> it = this.consumerTable.entrySet().iterator();
while (it.hasNext()) {
Entry<String, MQConsumerInner> entry = it.next();
MQConsumerInner impl = entry.getValue();
if (impl != null) {
Set<SubscriptionData> subList = impl.subscriptions();
if (subList != null) {
for (SubscriptionData subData : subList) {
topicList.add(subData.getTopic());
}
}
}
}
}
// Producer
{
Iterator<Entry<String, MQProducerInner>> it = this.producerTable.entrySet().iterator();
while (it.hasNext()) {
Entry<String, MQProducerInner> entry = it.next();
MQProducerInner impl = entry.getValue();
if (impl != null) {
Set<String> lst = impl.getPublishTopicList();
topicList.addAll(lst);
}
}
}
for (String topic : topicList) {
this.updateTopicRouteInfoFromNameServer(topic);
}
}
nameserver中保留了topic和broker的映射，因此定时遍历topic，和nameserver通信，若是远程的broker发生了变化，更新本地
// MQClientInstance
public boolean updateTopicRouteInfoFromNameServer(final String topic, boolean isDefault,
DefaultMQProducer defaultMQProducer) {
try {
if (this.lockNamesrv.tryLock(LOCK_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS)) {
try {
TopicRouteData topicRouteData;
if (isDefault && defaultMQProducer != null) {
topicRouteData = this.mQClientAPIImpl.getDefaultTopicRouteInfoFromNameServer(defaultMQProducer.getCreateTopicKey(),
1000 * 3);
if (topicRouteData != null) {
for (QueueData data : topicRouteData.getQueueDatas()) {
int queueNums = Math.min(defaultMQProducer.getDefaultTopicQueueNums(), data.getReadQueueNums());
data.setReadQueueNums(queueNums);
data.setWriteQueueNums(queueNums);
}
}
} else {
topicRouteData = this.mQClientAPIImpl.getTopicRouteInfoFromNameServer(topic, 1000 * 3);
}
if (topicRouteData != null) {
TopicRouteData old = this.topicRouteTable.get(topic);
boolean changed = topicRouteDataIsChange(old, topicRouteData);
if (!changed) {
changed = this.isNeedUpdateTopicRouteInfo(topic);
} else {
log.info("the topic[{}] route info changed, old[{}] ,new[{}]", topic, old, topicRouteData);
}
if (changed) {
TopicRouteData cloneTopicRouteData = topicRouteData.cloneTopicRouteData();
for (BrokerData bd : topicRouteData.getBrokerDatas()) {
this.brokerAddrTable.put(bd.getBrokerName(), bd.getBrokerAddrs());
}
// Update Pub info
{
TopicPublishInfo publishInfo = topicRouteData2TopicPublishInfo(topic, topicRouteData);
publishInfo.setHaveTopicRouterInfo(true);
Iterator<Entry<String, MQProducerInner>> it = this.producerTable.entrySet().iterator();
while (it.hasNext()) {
Entry<String, MQProducerInner> entry = it.next();
MQProducerInner impl = entry.getValue();
if (impl != null) {
impl.updateTopicPublishInfo(topic, publishInfo);
}
}
}
// Update sub info
{
Set<MessageQueue> subscribeInfo = topicRouteData2TopicSubscribeInfo(topic, topicRouteData);
Iterator<Entry<String, MQConsumerInner>> it = this.consumerTable.entrySet().iterator();
while (it.hasNext()) {
Entry<String, MQConsumerInner> entry = it.next();
MQConsumerInner impl = entry.getValue();
if (impl != null) {
impl.updateTopicSubscribeInfo(topic, subscribeInfo);
}
}
}
log.info("topicRouteTable.put. Topic = {}, TopicRouteData[{}]", topic, cloneTopicRouteData);
this.topicRouteTable.put(topic, cloneTopicRouteData);
return true;
}
}
...
return false;
}
创建对应header的request
// MQClientAPIImpl
public TopicRouteData getTopicRouteInfoFromNameServer(final String topic, final long timeoutMillis,
boolean allowTopicNotExist) throws MQClientException, InterruptedException, RemotingTimeoutException, RemotingSendRequestException, RemotingConnectException {
GetRouteInfoRequestHeader requestHeader = new GetRouteInfoRequestHeader();
requestHeader.setTopic(topic);
RemotingCommand request = RemotingCommand.createRequestCommand(RequestCode.GET_ROUTEINFO_BY_TOPIC, requestHeader);
RemotingCommand response = this.remotingClient.invokeSync(null, request, timeoutMillis);
assert response != null;
switch (response.getCode()) {
case ResponseCode.TOPIC_NOT_EXIST: {
if (allowTopicNotExist) {
log.warn("get Topic [{}] RouteInfoFromNameServer is not exist value", topic);
}
break;
}
case ResponseCode.SUCCESS: {
byte[] body = response.getBody();
if (body != null) {
return TopicRouteData.decode(body, TopicRouteData.class);
}
}
default:
break;
}
throw new MQClientException(response.getCode(), response.getRemark());
}
和nameserver通信是netty通信，本地保存了address和Channel的对应关系，找到对应的Channel，发送请求即可
// NettyRemotingClient
@Override
public RemotingCommand invokeSync(String addr, final RemotingCommand request, long timeoutMillis)
throws InterruptedException, RemotingConnectException, RemotingSendRequestException, RemotingTimeoutException {
long beginStartTime = System.currentTimeMillis();
final Channel channel = this.getAndCreateChannel(addr);
if (channel != null && channel.isActive()) {
try {
doBeforeRpcHooks(addr, request);
long costTime = System.currentTimeMillis() - beginStartTime;
if (timeoutMillis < costTime) {
throw new RemotingTimeoutException("invokeSync call timeout");
}
RemotingCommand response = this.invokeSyncImpl(channel, request, timeoutMillis - costTime);
doAfterRpcHooks(RemotingHelper.parseChannelRemoteAddr(channel), 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) {
if (nettyClientConfig.isClientCloseSocketIfTimeout()) {
this.closeChannel(addr, channel);
log.warn("invokeSync: close socket because of timeout, {}ms, {}", timeoutMillis, addr);
}
log.warn("invokeSync: wait response timeout exception, the channel[{}]", addr);
throw e;
}
} else {
this.closeChannel(addr, channel);
throw new RemotingConnectException(addr);
}
}
// NettyRemotingAbstract
public RemotingCommand invokeSyncImpl(final Channel channel, final RemotingCommand request,
final long timeoutMillis)
throws InterruptedException, RemotingSendRequestException, RemotingTimeoutException {
final int opaque = request.getOpaque();
try {
final ResponseFuture responseFuture = new ResponseFuture(channel, opaque, timeoutMillis, null, null);
this.responseTable.put(opaque, responseFuture);
final SocketAddress addr = channel.remoteAddress();
channel.writeAndFlush(request).addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture f) throws Exception {
if (f.isSuccess()) {
responseFuture.setSendRequestOK(true);
return;
} else {
responseFuture.setSendRequestOK(false);
}
responseTable.remove(opaque);
responseFuture.setCause(f.cause());
responseFuture.putResponse(null);
log.warn("send a request command to channel <" + addr + "> failed.");
}
});
RemotingCommand responseCommand = responseFuture.waitResponse(timeoutMillis);
if (null == responseCommand) {
if (responseFuture.isSendRequestOK()) {
throw new RemotingTimeoutException(RemotingHelper.parseSocketAddressAddr(addr), timeoutMillis,
responseFuture.getCause());
} else {
throw new RemotingSendRequestException(RemotingHelper.parseSocketAddressAddr(addr), responseFuture.getCause());
}
}
return responseCommand;
} finally {
this.responseTable.remove(opaque);
}
}
broker对topic的管理
producer发送消息到broker，若是消息所在的topic不存在，broker会自动创建topic。
普通的消息发送是同步消息，目前的版本发送的rquestCode为 SEND_MESSAGE_V2 ，在broker中对应处理器是SendMessageProcessor。在处理之前会对发送来的消息进行检查
// AbstractSendMessageProcessor
protected RemotingCommand msgCheck(final ChannelHandlerContext ctx,
final SendMessageRequestHeader requestHeader, final RemotingCommand response) {
if (!PermName.isWriteable(this.brokerController.getBrokerConfig().getBrokerPermission())
&& this.brokerController.getTopicConfigManager().isOrderTopic(requestHeader.getTopic())) {
response.setCode(ResponseCode.NO_PERMISSION);
response.setRemark("the broker[" + this.brokerController.getBrokerConfig().getBrokerIP1()
+ "] sending message is forbidden");
return response;
}
if (!TopicValidator.validateTopic(requestHeader.getTopic(), response)) {
return response;
}
if (TopicValidator.isNotAllowedSendTopic(requestHeader.getTopic(), response)) {
return response;
}
TopicConfig topicConfig =
this.brokerController.getTopicConfigManager().selectTopicConfig(requestHeader.getTopic());
if (null == topicConfig) {
int topicSysFlag = 0;
if (requestHeader.isUnitMode()) {
if (requestHeader.getTopic().startsWith(MixAll.RETRY_GROUP_TOPIC_PREFIX)) {
topicSysFlag = TopicSysFlag.buildSysFlag(false, true);
} else {
topicSysFlag = TopicSysFlag.buildSysFlag(true, false);
}
}
log.warn("the topic {} not exist, producer: {}", requestHeader.getTopic(), ctx.channel().remoteAddress());
topicConfig = this.brokerController.getTopicConfigManager().createTopicInSendMessageMethod(
requestHeader.getTopic(),
requestHeader.getDefaultTopic(),
RemotingHelper.parseChannelRemoteAddr(ctx.channel()),
requestHeader.getDefaultTopicQueueNums(), topicSysFlag);
if (null == topicConfig) {
if (requestHeader.getTopic().startsWith(MixAll.RETRY_GROUP_TOPIC_PREFIX)) {
topicConfig =
this.brokerController.getTopicConfigManager().createTopicInSendMessageBackMethod(
requestHeader.getTopic(), 1, PermName.PERM_WRITE | PermName.PERM_READ,
topicSysFlag);
}
}
if (null == topicConfig) {
response.setCode(ResponseCode.TOPIC_NOT_EXIST);
response.setRemark("topic[" + requestHeader.getTopic() + "] not exist, apply first please!"
+ FAQUrl.suggestTodo(FAQUrl.APPLY_TOPIC_URL));
return response;
}
}
int queueIdInt = requestHeader.getQueueId();
int idValid = Math.max(topicConfig.getWriteQueueNums(), topicConfig.getReadQueueNums());
if (queueIdInt >= idValid) {
String errorInfo = String.format("request queueId[%d] is illegal, %s Producer: %s",
queueIdInt,
topicConfig.toString(),
RemotingHelper.parseChannelRemoteAddr(ctx.channel()));
log.warn(errorInfo);
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark(errorInfo);
return response;
}
return response;
}
若是topic存在直接返回，若是不存在，在broker端创建topic并放进缓存和json文件中。
创建topic的部分在TopicConfigManager中
// TopicConfigManager
public TopicConfig createTopicInSendMessageMethod(final String topic, final String defaultTopic,
final String remoteAddress, final int clientDefaultTopicQueueNums, final int topicSysFlag) {
TopicConfig topicConfig = null;
boolean createNew = false;
try {
if (this.lockTopicConfigTable.tryLock(LOCK_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS)) {
try {
topicConfig = this.topicConfigTable.get(topic);
if (topicConfig != null)
return topicConfig;
TopicConfig defaultTopicConfig = this.topicConfigTable.get(defaultTopic);
if (defaultTopicConfig != null) {
if (defaultTopic.equals(TopicValidator.AUTO_CREATE_TOPIC_KEY_TOPIC)) {
if (!this.brokerController.getBrokerConfig().isAutoCreateTopicEnable()) {
defaultTopicConfig.setPerm(PermName.PERM_READ | PermName.PERM_WRITE);
}
}
if (PermName.isInherited(defaultTopicConfig.getPerm())) {
topicConfig = new TopicConfig(topic);
int queueNums =
clientDefaultTopicQueueNums > defaultTopicConfig.getWriteQueueNums() ? defaultTopicConfig
.getWriteQueueNums() : clientDefaultTopicQueueNums;
if (queueNums < 0) {
queueNums = 0;
}
topicConfig.setReadQueueNums(queueNums);
topicConfig.setWriteQueueNums(queueNums);
int perm = defaultTopicConfig.getPerm();
perm &= ~PermName.PERM_INHERIT;
topicConfig.setPerm(perm);
topicConfig.setTopicSysFlag(topicSysFlag);
topicConfig.setTopicFilterType(defaultTopicConfig.getTopicFilterType());
} else {
log.warn("Create new topic failed, because the default topic[{}] has no perm [{}] producer:[{}]",
defaultTopic, defaultTopicConfig.getPerm(), remoteAddress);
}
} else {
log.warn("Create new topic failed, because the default topic[{}] not exist. producer:[{}]",
defaultTopic, remoteAddress);
}
if (topicConfig != null) {
log.info("Create new topic by default topic:[{}] config:[{}] producer:[{}]",
defaultTopic, topicConfig, remoteAddress);
this.topicConfigTable.put(topic, topicConfig);
this.dataVersion.nextVersion();
createNew = true;
this.persist();
}
} finally {
this.lockTopicConfigTable.unlock();
}
}
} catch (InterruptedException e) {
log.error("createTopicInSendMessageMethod exception", e);
}
if (createNew) {
this.brokerController.registerBrokerAll(false, true, true);
}
return topicConfig;
}
如果是新创建的topic，broker会主动向nameserve注册新创建的topic
// BrokerController
private void doRegisterBrokerAll(boolean checkOrderConfig, boolean oneway,
TopicConfigSerializeWrapper topicConfigWrapper) {
List<RegisterBrokerResult> registerBrokerResultList = this.brokerOuterAPI.registerBrokerAll(
this.brokerConfig.getBrokerClusterName(),
this.getBrokerAddr(),
this.brokerConfig.getBrokerName(),
this.brokerConfig.getBrokerId(),
this.getHAServerAddr(),
topicConfigWrapper,
this.filterServerManager.buildNewFilterServerList(),
oneway,
this.brokerConfig.getRegisterBrokerTimeoutMills(),
this.brokerConfig.isCompressedRegister());
if (registerBrokerResultList.size() > 0) {
RegisterBrokerResult registerBrokerResult = registerBrokerResultList.get(0);
if (registerBrokerResult != null) {
if (this.updateMasterHAServerAddrPeriodically && registerBrokerResult.getHaServerAddr() != null) {
this.messageStore.updateHaMasterAddress(registerBrokerResult.getHaServerAddr());
}
this.slaveSynchronize.setMasterAddr(registerBrokerResult.getMasterAddr());
if (checkOrderConfig) {
this.getTopicConfigManager().updateOrderTopicConfig(registerBrokerResult.getKvTable());
}
}
}
}
通信的部分是通过netty给nameserver发送消息
// BrokerOuterAPI
private RegisterBrokerResult registerBroker(
final String namesrvAddr,
final boolean oneway,
final int timeoutMills,
final RegisterBrokerRequestHeader requestHeader,
final byte[] body
) throws RemotingCommandException, MQBrokerException, RemotingConnectException, RemotingSendRequestException, RemotingTimeoutException,
InterruptedException {
RemotingCommand request = RemotingCommand.createRequestCommand(RequestCode.REGISTER_BROKER, requestHeader);
request.setBody(body);
if (oneway) {
try {
this.remotingClient.invokeOneway(namesrvAddr, request, timeoutMills);
} catch (RemotingTooMuchRequestException e) {
// Ignore
}
return null;
}
RemotingCommand response = this.remotingClient.invokeSync(namesrvAddr, request, timeoutMills);
assert response != null;
switch (response.getCode()) {
case ResponseCode.SUCCESS: {
RegisterBrokerResponseHeader responseHeader =
(RegisterBrokerResponseHeader) response.decodeCommandCustomHeader(RegisterBrokerResponseHeader.class);
RegisterBrokerResult result = new RegisterBrokerResult();
result.setMasterAddr(responseHeader.getMasterAddr());
result.setHaServerAddr(responseHeader.getHaServerAddr());
if (response.getBody() != null) {
result.setKvTable(KVTable.decode(response.getBody(), KVTable.class));
}
return result;
}
default:
break;
}
throw new MQBrokerException(response.getCode(), response.getRemark());
}
这里会发现，nameserver是无状态的，也不进行持久化，持久化是在broker中进行的，broker启动后会向nameserver注册自己，在nameserver中只是缓存broker和topic的映射关系。
