> 文档中心 > rocketmq源码④-Consumer的启动、接受消息、broker路由

rocketmq源码④-Consumer的启动、接受消息、broker路由

文档中心

添加了注释的源码
https://github.com/WangTingYeYe/rocketmq_source

前提介绍：

一定要先看前面的几篇文章，了解rocketmq的基本概念和架构设计之后再看本篇
在这里插入图片描述

消费模式

消费者以消费者组的模式开展。消费者组之间有集群模式和广播模式两种消费模式。然后消费模式有推模式和拉模式。推模式是由拉模式封装组成。
集群模式下，消费队列负载均衡的通用原理：一个消费队列同一时间只能被一个消费者消费，而一个消费者可以同时消费多个队列。
消息顺序：RocketMQ只支持一个队列上的局部消息顺序，不保证全局消息顺序。要实现顺序消息，可以把有序的消息指定为一个queue，或者给Topic只指定一个Queue，这个不推荐。

官方样例

官方提供的例子：

/* * 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.rocketmq.example.quickstart;import java.util.List;import org.apache.rocketmq.client.consumer.AllocateMessageQueueStrategy;import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;import org.apache.rocketmq.client.exception.MQClientException;import org.apache.rocketmq.common.consumer.ConsumeFromWhere;import org.apache.rocketmq.common.message.MessageExt;/** * This example shows how to subscribe and consume messages using providing {@link DefaultMQPushConsumer}. */public class Consumer {    public static void main(String[] args) throws InterruptedException, MQClientException { /*  * Instantiate with specified consumer group name.  */ DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("please_rename_unique_group_name_4"); /*  * Specify name server addresses.  *   *  * Alternatively, you may specify name server addresses via exporting environmental variable: NAMESRV_ADDR  * 
  * {@code  * consumer.setNamesrvAddr("name-server1-ip:9876;name-server2-ip:9876");  * }  * 
  */ consumer.setNamesrvAddr("127.0.0.1:9876"); /*  * Specify where to start in case the specified consumer group is a brand new one.  */ consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET); /*  * Subscribe one more more topics to consume.  */ consumer.subscribe("TopicTest", "*"); /*  *  Register callback to execute on arrival of messages fetched from brokers.  */ consumer.registerMessageListener(new MessageListenerConcurrently() {     @Override     public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs,  ConsumeConcurrentlyContext context) {  System.out.printf("%s Receive New Messages: %s %n", Thread.currentThread().getName(), msgs);  return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;     } }); /*  *  Launch the consumer instance.  */ consumer.start(); System.out.printf("Consumer Started.%n");    }} 
consumer.start()

1、初始化mQClientFactory
 2、根据消费模式（集群消费、广播消费）不同方式load offset
 3、根据处理模式(顺序、并发) 开启不同的定时任务
 4、启动mQClientFactory

  //消费者端实际启动过程    public synchronized void start() throws MQClientException { switch (this.serviceState) {     case CREATE_JUST:  log.info("the consumer [{}] start beginning. messageModel={}, isUnitMode={}", this.defaultMQPushConsumer.getConsumerGroup(),      this.defaultMQPushConsumer.getMessageModel(), this.defaultMQPushConsumer.isUnitMode());  this.serviceState = ServiceState.START_FAILED;  this.checkConfig();  this.copySubscription();  if (this.defaultMQPushConsumer.getMessageModel() == MessageModel.CLUSTERING) {      this.defaultMQPushConsumer.changeInstanceNameToPID();  }  //K2 客户端创建工厂，这个是核心对象  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);  }  // 广播消费，都是本机自己保存的offset。所以直接会从本地加载offeset  // 集群消费，不用加载需要从远程同步offset  this.offsetStore.load();  //根据客户端配置实例化不同的consumeMessageService  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());  }  // 根据不同的处理方式  // 顺序消息  每隔20s锁定对应的消费队列  // 并发消息  每隔15ms清理一下失效消息  this.consumeMessageService.start();  //注册本地的消费者组缓存。  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;  break;     case RUNNING:     case START_FAILED:     case SHUTDOWN_ALREADY:  throw new MQClientException("The PushConsumer service state not OK, maybe started once, "      + this.serviceState      + FAQUrl.suggestTodo(FAQUrl.CLIENT_SERVICE_NOT_OK),      null);     default:  break; } this.updateTopicSubscribeInfoWhenSubscriptionChanged(); this.mQClientFactory.checkClientInBroker(); this.mQClientFactory.sendHeartbeatToAllBrokerWithLock(); this.mQClientFactory.rebalanceImmediately();    }
MQClientInstance#start

这里启动的逻辑跟前一篇的 producer启动流程代码复用
 1、启动nettry客户端用于发送请求
 2、开启一批定时任务（更新订阅topic信息、更新nameServer地址、同步消息进度等等）
 3、开启拉取消息的线程(push模式和pull模式底层都是 客户端主动向broker拉取消息)

  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      // 启动了nettry客户端      this.mQClientAPIImpl.start();      // Start various schedule tasks      this.startScheduledTask();      // Start pull service      this.pullMessageService.start();      // Start rebalance service      //K2 客户端负载均衡      this.rebalanceService.start();      // Start push service      this.defaultMQProducer.getDefaultMQProducerImpl().start(false);      log.info("the client factory [{}] start OK", this.clientId);      this.serviceState = ServiceState.RUNNING;      break;  case START_FAILED:      throw new MQClientException("The Factory object[" + this.getClientId() + "] has been created before, and failed.", null);  default:      break;     } }    }
开启一批定时任务
private void startScheduledTask() { if (null == this.clientConfig.getNamesrvAddr()) {     this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {  @Override  public void run() {      try {   // 更新nameServer地址。   MQClientInstance.this.mQClientAPIImpl.fetchNameServerAddr();      } catch (Exception e) {   log.error("ScheduledTask fetchNameServerAddr exception", e);      }  }     }, 1000 * 10, 1000 * 60 * 2, TimeUnit.MILLISECONDS); } this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {     @Override     public void run() {  try {      //从nameServer更新主题路由信息      MQClientInstance.this.updateTopicRouteInfoFromNameServer();  } catch (Exception e) {      log.error("ScheduledTask updateTopicRouteInfoFromNameServer exception", e);  }     } }, 10, this.clientConfig.getPollNameServerInterval(), TimeUnit.MILLISECONDS); this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {     @Override     public void run() {  try {      //清除下线的broker      MQClientInstance.this.cleanOfflineBroker();      //向所有broker发送心跳，并记录broker的版本      MQClientInstance.this.sendHeartbeatToAllBrokerWithLock();  } catch (Exception e) {      log.error("ScheduledTask sendHeartbeatToAllBroker exception", e);  }     } }, 1000, this.clientConfig.getHeartbeatBrokerInterval(), TimeUnit.MILLISECONDS); this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {     @Override     public void run() {  try {      //将消费进度向Broker同步      MQClientInstance.this.persistAllConsumerOffset();  } catch (Exception e) {      log.error("ScheduledTask persistAllConsumerOffset exception", e);  }     } }, 1000 * 10, this.clientConfig.getPersistConsumerOffsetInterval(), TimeUnit.MILLISECONDS); this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {     @Override     public void run() {  try {      MQClientInstance.this.adjustThreadPool();  } catch (Exception e) {      log.error("ScheduledTask adjustThreadPool exception", e);  }     } }, 1, 1, TimeUnit.MINUTES);    }
最核心的链路 开启拉取消息的线程


this.pullMessageService.start()

org.apache.rocketmq.client.impl.consumer.PullMessageService#run




只要客户端没有关闭，就会不停的从pullRequestQueue中获取pullRequest请求，然后执行通过网络发送请求。


PullRequest里有messageQueue和processQueue，其中messageQueue负责拉取消息，拉取到后，将消息存入processQueue，进行处理。 存入后就可以清空messageQueue，继续拉取了。


这里是比较长见的中间件网络请求设计，请求对象放在一个队列里。通过一个线程不停从队列拿取对象并且执行网络请求。这样做的好处是，需要发送网络请求的地方只需要将请求对象封装好往队列放一下就好了,实现了代码的解耦。值得学习哦

 public void run() { log.info(this.getServiceName() + " service started"); while (!this.isStopped()) {     try {  //拉取消息的请求队列,当需要去拉去消息时，会往该队列中push一个拉消息的请求  PullRequest pullRequest = this.pullRequestQueue.take();  //处理请求  this.pullMessage(pullRequest);     } catch (InterruptedException ignored) {     } catch (Exception e) {  log.error("Pull Message Service Run Method exception", e);     } } log.info(this.getServiceName() + " service end");    }
pullMessage 真正发送pull请求的逻辑

此处可以看到最后都是通过pull模式来拉取消息

    private void pullMessage(final PullRequest pullRequest) { final MQConsumerInner consumer = this.mQClientFactory.selectConsumer(pullRequest.getConsumerGroup()); if (consumer != null) {     DefaultMQPushConsumerImpl impl = (DefaultMQPushConsumerImpl) consumer;     //K2 推模式的消费者最终还是会使用拉消息的方式     impl.pullMessage(pullRequest); } else {     log.warn("No matched consumer for the PullRequest {}, drop it", pullRequest); }    }

拉取消息
 1、找到要拉去的队列
 2、要进行流控（客户端得保证自己处理的过来、也得保护broker扛不住）
 3、发送网络请求拉去消息
 4、回调业务方注册的回调函数(就是业务代码里面针对消息的处理逻辑)

    //K2 拉取消息的核心流程    public void pullMessage(final PullRequest pullRequest) { //获取要处理的消息：ProcessQueue final ProcessQueue processQueue = pullRequest.getProcessQueue(); //如果队列被抛弃，直接返回 if (processQueue.isDropped()) {     log.info("the pull request[{}] is dropped.", pullRequest.toString());     return; } //先更新时间戳 pullRequest.getProcessQueue().setLastPullTimestamp(System.currentTimeMillis()); try {     this.makeSureStateOK(); } catch (MQClientException e) {     log.warn("pullMessage exception, consumer state not ok", e);     this.executePullRequestLater(pullRequest, pullTimeDelayMillsWhenException);     return; } //如果处理队列被挂起，延迟1S后再执行。 if (this.isPause()) {     log.warn("consumer was paused, execute pull request later. instanceName={}, group={}", this.defaultMQPushConsumer.getInstanceName(), this.defaultMQPushConsumer.getConsumerGroup());     this.executePullRequestLater(pullRequest, PULL_TIME_DELAY_MILLS_WHEN_SUSPEND);     return; } //获得最大待处理消息数量 long cachedMessageCount = processQueue.getMsgCount().get(); //获得最大待处理消息大小 long cachedMessageSizeInMiB = processQueue.getMsgSize().get() / (1024 * 1024); //从数量进行流控 if (cachedMessageCount > this.defaultMQPushConsumer.getPullThresholdForQueue()) {     this.executePullRequestLater(pullRequest, PULL_TIME_DELAY_MILLS_WHEN_FLOW_CONTROL);     if ((queueFlowControlTimes++ % 1000) == 0) {  log.warn(      "the cached message count exceeds the threshold {}, so do flow control, minOffset={}, maxOffset={}, count={}, size={} MiB, pullRequest={}, flowControlTimes={}",      this.defaultMQPushConsumer.getPullThresholdForQueue(), processQueue.getMsgTreeMap().firstKey(), processQueue.getMsgTreeMap().lastKey(), cachedMessageCount, cachedMessageSizeInMiB, pullRequest, queueFlowControlTimes);     }     return; } //从消息大小进行流控 if (cachedMessageSizeInMiB > this.defaultMQPushConsumer.getPullThresholdSizeForQueue()) {     this.executePullRequestLater(pullRequest, PULL_TIME_DELAY_MILLS_WHEN_FLOW_CONTROL);     if ((queueFlowControlTimes++ % 1000) == 0) {  log.warn(      "the cached message size exceeds the threshold {} MiB, so do flow control, minOffset={}, maxOffset={}, count={}, size={} MiB, pullRequest={}, flowControlTimes={}",      this.defaultMQPushConsumer.getPullThresholdSizeForQueue(), processQueue.getMsgTreeMap().firstKey(), processQueue.getMsgTreeMap().lastKey(), cachedMessageCount, cachedMessageSizeInMiB, pullRequest, queueFlowControlTimes);     }     return; } if (!this.consumeOrderly) {     if (processQueue.getMaxSpan() > this.defaultMQPushConsumer.getConsumeConcurrentlyMaxSpan()) {  this.executePullRequestLater(pullRequest, PULL_TIME_DELAY_MILLS_WHEN_FLOW_CONTROL);  if ((queueMaxSpanFlowControlTimes++ % 1000) == 0) {      log.warn(   "the queue's messages, span too long, so do flow control, minOffset={}, maxOffset={}, maxSpan={}, pullRequest={}, flowControlTimes={}",   processQueue.getMsgTreeMap().firstKey(), processQueue.getMsgTreeMap().lastKey(), processQueue.getMaxSpan(),   pullRequest, queueMaxSpanFlowControlTimes);  }  return;     } } else {     if (processQueue.isLocked()) {  if (!pullRequest.isLockedFirst()) {      final long offset = this.rebalanceImpl.computePullFromWhere(pullRequest.getMessageQueue());      boolean brokerBusy = offset < pullRequest.getNextOffset();      log.info("the first time to pull message, so fix offset from broker. pullRequest: {} NewOffset: {} brokerBusy: {}",   pullRequest, offset, brokerBusy);      if (brokerBusy) {   log.info("[NOTIFYME]the first time to pull message, but pull request offset larger than broker consume offset. pullRequest: {} NewOffset: {}",pullRequest, offset);      }      pullRequest.setLockedFirst(true);      pullRequest.setNextOffset(offset);  }     } else {  this.executePullRequestLater(pullRequest, pullTimeDelayMillsWhenException);  log.info("pull message later because not locked in broker, {}", pullRequest);  return;     } } final SubscriptionData subscriptionData = this.rebalanceImpl.getSubscriptionInner().get(pullRequest.getMessageQueue().getTopic()); if (null == subscriptionData) {     this.executePullRequestLater(pullRequest, pullTimeDelayMillsWhenException);     log.warn("find the consumer's subscription failed, {}", pullRequest);     return; } final long beginTimestamp = System.currentTimeMillis(); //K2 客户端 默认的拉取的回调函数，在拉取到消息后会进入这个方法处理。 PullCallback pullCallback = new PullCallback() {     @Override     public void onSuccess(PullResult pullResult) {  if (pullResult != null) {      pullResult = DefaultMQPushConsumerImpl.this.pullAPIWrapper.processPullResult(pullRequest.getMessageQueue(), pullResult,   subscriptionData);      switch (pullResult.getPullStatus()) {   case FOUND:long prevRequestOffset = pullRequest.getNextOffset();pullRequest.setNextOffset(pullResult.getNextBeginOffset());long pullRT = System.currentTimeMillis() - beginTimestamp;DefaultMQPushConsumerImpl.this.getConsumerStatsManager().incPullRT(pullRequest.getConsumerGroup(),    pullRequest.getMessageQueue().getTopic(), pullRT);long firstMsgOffset = Long.MAX_VALUE;if (pullResult.getMsgFoundList() == null || pullResult.getMsgFoundList().isEmpty()) {    DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);} else {    firstMsgOffset = pullResult.getMsgFoundList().get(0).getQueueOffset();    DefaultMQPushConsumerImpl.this.getConsumerStatsManager().incPullTPS(pullRequest.getConsumerGroup(), pullRequest.getMessageQueue().getTopic(), pullResult.getMsgFoundList().size());    boolean dispatchToConsume = processQueue.putMessage(pullResult.getMsgFoundList());    //K2 消费者消息服务处理消费到的消息    DefaultMQPushConsumerImpl.this.consumeMessageService.submitConsumeRequest( pullResult.getMsgFoundList(), processQueue, pullRequest.getMessageQueue(), dispatchToConsume);    if (DefaultMQPushConsumerImpl.this.defaultMQPushConsumer.getPullInterval() > 0) { DefaultMQPushConsumerImpl.this.executePullRequestLater(pullRequest,     DefaultMQPushConsumerImpl.this.defaultMQPushConsumer.getPullInterval());    } else { DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);    }}if (pullResult.getNextBeginOffset() < prevRequestOffset    || firstMsgOffset < prevRequestOffset) {    log.warn( "[BUG] pull message result maybe data wrong, nextBeginOffset: {} firstMsgOffset: {} prevRequestOffset: {}", pullResult.getNextBeginOffset(), firstMsgOffset, prevRequestOffset);}break;   case NO_NEW_MSG:pullRequest.setNextOffset(pullResult.getNextBeginOffset());DefaultMQPushConsumerImpl.this.correctTagsOffset(pullRequest);DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);break;   case NO_MATCHED_MSG:pullRequest.setNextOffset(pullResult.getNextBeginOffset());DefaultMQPushConsumerImpl.this.correctTagsOffset(pullRequest);DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);break;   case OFFSET_ILLEGAL:log.warn("the pull request offset illegal, {} {}",    pullRequest.toString(), pullResult.toString());pullRequest.setNextOffset(pullResult.getNextBeginOffset());pullRequest.getProcessQueue().setDropped(true);DefaultMQPushConsumerImpl.this.executeTaskLater(new Runnable() {    @Override    public void run() { try {     DefaultMQPushConsumerImpl.this.offsetStore.updateOffset(pullRequest.getMessageQueue(),  pullRequest.getNextOffset(), false);     DefaultMQPushConsumerImpl.this.offsetStore.persist(pullRequest.getMessageQueue());     DefaultMQPushConsumerImpl.this.rebalanceImpl.removeProcessQueue(pullRequest.getMessageQueue());     log.warn("fix the pull request offset, {}", pullRequest); } catch (Throwable e) {     log.error("executeTaskLater Exception", e); }    }}, 10000);break;   default:break;      }  }     }     @Override     public void onException(Throwable e) {  if (!pullRequest.getMessageQueue().getTopic().startsWith(MixAll.RETRY_GROUP_TOPIC_PREFIX)) {      log.warn("execute the pull request exception", e);  }  DefaultMQPushConsumerImpl.this.executePullRequestLater(pullRequest, pullTimeDelayMillsWhenException);     } }; boolean commitOffsetEnable = false; long commitOffsetValue = 0L; if (MessageModel.CLUSTERING == this.defaultMQPushConsumer.getMessageModel()) {     commitOffsetValue = this.offsetStore.readOffset(pullRequest.getMessageQueue(), ReadOffsetType.READ_FROM_MEMORY);     if (commitOffsetValue > 0) {  commitOffsetEnable = true;     } } String subExpression = null; boolean classFilter = false; SubscriptionData sd = this.rebalanceImpl.getSubscriptionInner().get(pullRequest.getMessageQueue().getTopic()); if (sd != null) {     if (this.defaultMQPushConsumer.isPostSubscriptionWhenPull() && !sd.isClassFilterMode()) {  subExpression = sd.getSubString();     }     classFilter = sd.isClassFilterMode(); } int sysFlag = PullSysFlag.buildSysFlag(     commitOffsetEnable, // commitOffset     true, // suspend     subExpression != null, // subscription     classFilter // class filter ); try {     //K2 客户端实际与服务器交互，拉取消息的地方     this.pullAPIWrapper.pullKernelImpl(  pullRequest.getMessageQueue(),  subExpression,  subscriptionData.getExpressionType(),  subscriptionData.getSubVersion(),  pullRequest.getNextOffset(),  this.defaultMQPushConsumer.getPullBatchSize(),  sysFlag,  commitOffsetValue,  BROKER_SUSPEND_MAX_TIME_MILLIS,  CONSUMER_TIMEOUT_MILLIS_WHEN_SUSPEND,  CommunicationMode.ASYNC,  pullCallback     ); } catch (Exception e) {     log.error("pullKernelImpl exception", e);     this.executePullRequestLater(pullRequest, pullTimeDelayMillsWhenException); }    }
什么时候往pullRequestQueue 里面放请求对象呢？

在负载均衡线程做完负载均衡处理后，会第一次往pullRequestQueue放请求对象


this.rebalanceService.start();

org.apache.rocketmq.client.impl.consumer.RebalanceService#run

org.apache.rocketmq.client.impl.factory.MQClientInstance#doRebalance

org.apache.rocketmq.client.impl.consumer.MQConsumerInner#doRebalance

org.apache.rocketmq.client.impl.consumer.DefaultMQPushConsumerImpl#doRebalance

org.apache.rocketmq.client.impl.consumer.RebalanceImpl#doRebalance

org.apache.rocketmq.client.impl.consumer.RebalanceImpl#rebalanceByTopic

org.apache.rocketmq.client.impl.consumer.RebalanceImpl#updateProcessQueueTableInRebalance

org.apache.rocketmq.client.impl.consumer.RebalancePushImpl#dispatchPullRequest

















    @Override    public void dispatchPullRequest(List<PullRequest> pullRequestList) { for (PullRequest pullRequest : pullRequestList) {     this.defaultMQPushConsumerImpl.executePullRequestImmediately(pullRequest);     log.info("doRebalance, {}, add a new pull request {}", consumerGroup, pullRequest); }    }

在消息处理完后又重新将pullRequest塞会pullRequestQueue

 //K2 客户端 默认的拉取的回调函数，在拉取到消息后会进入这个方法处理。 PullCallback pullCallback = new PullCallback() {     @Override     public void onSuccess(PullResult pullResult) {  if (pullResult != null) {      pullResult = DefaultMQPushConsumerImpl.this.pullAPIWrapper.processPullResult(pullRequest.getMessageQueue(), pullResult,   subscriptionData);      switch (pullResult.getPullStatus()) {   case FOUND:long prevRequestOffset = pullRequest.getNextOffset();pullRequest.setNextOffset(pullResult.getNextBeginOffset());long pullRT = System.currentTimeMillis() - beginTimestamp;DefaultMQPushConsumerImpl.this.getConsumerStatsManager().incPullRT(pullRequest.getConsumerGroup(),    pullRequest.getMessageQueue().getTopic(), pullRT);long firstMsgOffset = Long.MAX_VALUE;if (pullResult.getMsgFoundList() == null || pullResult.getMsgFoundList().isEmpty()) {    DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);} else {    firstMsgOffset = pullResult.getMsgFoundList().get(0).getQueueOffset();    DefaultMQPushConsumerImpl.this.getConsumerStatsManager().incPullTPS(pullRequest.getConsumerGroup(), pullRequest.getMessageQueue().getTopic(), pullResult.getMsgFoundList().size());    boolean dispatchToConsume = processQueue.putMessage(pullResult.getMsgFoundList());    //K2 消费者消息服务处理消费到的消息    DefaultMQPushConsumerImpl.this.consumeMessageService.submitConsumeRequest( pullResult.getMsgFoundList(), processQueue, pullRequest.getMessageQueue(), dispatchToConsume);    if (DefaultMQPushConsumerImpl.this.defaultMQPushConsumer.getPullInterval() > 0) { DefaultMQPushConsumerImpl.this.executePullRequestLater(pullRequest,     DefaultMQPushConsumerImpl.this.defaultMQPushConsumer.getPullInterval());    } else { DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);    }}if (pullResult.getNextBeginOffset() < prevRequestOffset    || firstMsgOffset < prevRequestOffset) {    log.warn( "[BUG] pull message result maybe data wrong, nextBeginOffset: {} firstMsgOffset: {} prevRequestOffset: {}", pullResult.getNextBeginOffset(), firstMsgOffset, prevRequestOffset);}break;   case NO_NEW_MSG:pullRequest.setNextOffset(pullResult.getNextBeginOffset());DefaultMQPushConsumerImpl.this.correctTagsOffset(pullRequest);DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);break;   case NO_MATCHED_MSG:pullRequest.setNextOffset(pullResult.getNextBeginOffset());DefaultMQPushConsumerImpl.this.correctTagsOffset(pullRequest);DefaultMQPushConsumerImpl.this.executePullRequestImmediately(pullRequest);break;   case OFFSET_ILLEGAL:log.warn("the pull request offset illegal, {} {}",    pullRequest.toString(), pullResult.toString());pullRequest.setNextOffset(pullResult.getNextBeginOffset());pullRequest.getProcessQueue().setDropped(true);DefaultMQPushConsumerImpl.this.executeTaskLater(new Runnable() {    @Override    public void run() { try {     DefaultMQPushConsumerImpl.this.offsetStore.updateOffset(pullRequest.getMessageQueue(),  pullRequest.getNextOffset(), false);     DefaultMQPushConsumerImpl.this.offsetStore.persist(pullRequest.getMessageQueue());     DefaultMQPushConsumerImpl.this.rebalanceImpl.removeProcessQueue(pullRequest.getMessageQueue());     log.warn("fix the pull request offset, {}", pullRequest); } catch (Throwable e) {     log.error("executeTaskLater Exception", e); }    }}, 10000);break;   default:break;      }  }     }