消息中间件 RocketMQ 源码解析 —— 调试环境搭建

摘要: 原创出处 www.iocoder.cn/RocketMQ/bu… 「芋道源码」欢迎转载，保留摘要，谢谢！

• 0. 友情提示
• 1. 依赖工具
• 2. 源码拉取
• 3. 启动 RocketMQ Namesrv
• 4. 启动 RocketMQ Broker
• 5. 启动 RocketMQ Producer
• 6. 启动 RocketMQ Consumer
• 666. 彩蛋

0. 友情提示

阅读源码之前，建议胖友对 RocketMQ 的文档已经熟读。目前 RocketMQ 4 的中文文档很少，所以英文不太好的胖友，推荐看看如下资料：

• 《RocketMQ 用户指南》 基于 RocketMQ 3 的版本。
• 《RocketMQ 原理简介》 基于 RocketMQ 3 的版本。
• 《RocketMQ 最佳实践》 基于 RocketMQ 3 的版本。
• 《阿里云 —— 消息队列 MQ》 阿里云的消息队列，就是 RocketMQ 的云服务。

1. 依赖工具

• JDK ：1.8+
• Maven
• IntelliJ IDEA

2. 源码拉取

从官方仓库 [ github.com/apache/rock… ) Fork 出属于自己的仓库。为什么要 Fork ？既然开始阅读、调试源码，我们可能会写一些注释，有了自己的仓库，可以进行自由的提交。:smiling_imp:

使用 IntelliJ IDEA 从 Fork 出来的仓库拉取代码。拉取完成后， Maven 会下载依赖包，可能会花费一些时间，耐心等待下。

在等待的过程中，我来简单说下，搭建调试环境的过程：

1. 启动 RocketMQ Namesrv
2. 启动 RocketMQ Broker
3. 启动 RocketMQ Producer
4. 启动 RocketMQ Consumer

最小化的 RocketMQ 的环境，暂时不考虑 Namesrv 集群、Broker 集群、Consumer 集群。

:smiling_imp: 另外，本文使用的 RocketMQ 版本是 4.4.0-SNAPSHOT 。

3. 启动 RocketMQ Namesrv

打开 org.apache.rocketmq.namesrv.NameServerInstanceTest 单元测试类，参考 #startup() 方法，我们编写 #main(String[] args) 静态方法，代码如下：

// NameServerInstanceTest.java

public static void main(String[] args) throws Exception {
    // NamesrvConfig 配置
    final NamesrvConfig namesrvConfig = new NamesrvConfig();
    // NettyServerConfig 配置
    final NettyServerConfig nettyServerConfig = new NettyServerConfig();
    nettyServerConfig.setListenPort(9876); // 设置端口
    // 创建 NamesrvController 对象，并启动
    NamesrvController namesrvController = new NamesrvController(namesrvConfig, nettyServerConfig);
    namesrvController.initialize();
    namesrvController.start();
    // 睡觉，就不起来
    Thread.sleep(DateUtils.MILLIS_PER_DAY);
}
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然后，右键运行，RocketMQ Namesrv 就启动完成。输出日志如下：

17:54:03.354 [NettyEventExecutor] INFO  RocketmqRemoting - NettyEventExecutor service started
17:54:03.355 [FileWatchService] INFO  RocketmqCommon - FileWatchService service started
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最后，这是一个 可选 的步骤，命令行中输入 telnet 127.0.0.1 9876 ，看看是否能连接上 RocketMQ Namesrv 。

4. 启动 RocketMQ Broker

打开 org.apache.rocketmq.broker.BrokerControllerTest 单元测试类，参考 #testBrokerRestart() 方法，我们编写 #main(String[] args) 方法，代码如下：

// BrokerControllerTest.java

public static void main(String[] args) throws Exception {
    // 设置版本号
    System.setProperty(RemotingCommand.REMOTING_VERSION_KEY, Integer.toString(MQVersion.CURRENT_VERSION));
    // NettyServerConfig 配置
    final NettyServerConfig nettyServerConfig = new NettyServerConfig();
    nettyServerConfig.setListenPort(10911);
    // BrokerConfig 配置
    final BrokerConfig brokerConfig = new BrokerConfig();
    brokerConfig.setBrokerName("broker-a");
    brokerConfig.setNamesrvAddr("127.0.0.1:9876");
    // MessageStoreConfig 配置
    final MessageStoreConfig messageStoreConfig = new MessageStoreConfig();
    messageStoreConfig.setDeleteWhen("04");
    messageStoreConfig.setFileReservedTime(48);
    messageStoreConfig.setFlushDiskType(FlushDiskType.ASYNC_FLUSH);
    messageStoreConfig.setDuplicationEnable(false);

//        BrokerPathConfigHelper.setBrokerConfigPath("/Users/yunai/百度云同步盘/开发/Javascript/Story/incubator-rocketmq/conf/broker.conf");
    // 创建 BrokerController 对象，并启动
    BrokerController brokerController = new BrokerController(//
            brokerConfig, //
            nettyServerConfig, //
            new NettyClientConfig(), //
            messageStoreConfig);
    brokerController.initialize();
    brokerController.start();
    // 睡觉，就不起来
    System.out.println("你猜");
    Thread.sleep(DateUtils.MILLIS_PER_DAY);
}
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然后，右键运行，RocketMQ Broker 就启动完成了。输出日志如下：

你猜
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• 不要懵逼，我们打开下 RocketMQ Namesrv 那，已经输出日志如下：

  18:17:30.443 [NettyServerCodecThread_5] INFO  RocketmqRemoting - NETTY SERVER PIPELINE: channelRegistered 127.0.0.1:63847
  18:17:30.443 [NettyServerCodecThread_5] INFO  RocketmqRemoting - NETTY SERVER PIPELINE: channelActive, the channel[127.0.0.1:63847]
  18:17:30.457 [RemotingExecutorThread_4] DEBUG RocketmqNamesrv - receive request, 103 127.0.0.1:63847 RemotingCommand [code=103, language=JAVA, version=275, opaque=0, flag(B)=0, remark=null, extFields={brokerId=0, bodyCrc32=1880081823, clusterName=DefaultCluster, brokerAddr=192.168.3.26:10911, haServerAddr=192.168.3.26:10912, compressed=false, brokerName=broker-a}, serializeTypeCurrentRPC=JSON]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new topic registered, BenchmarkTest QueueData [brokerName=broker-a, readQueueNums=1024, writeQueueNums=1024, perm=6, topicSynFlag=0]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new topic registered, OFFSET_MOVED_EVENT QueueData [brokerName=broker-a, readQueueNums=1, writeQueueNums=1, perm=6, topicSynFlag=0]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new topic registered, broker-a QueueData [brokerName=broker-a, readQueueNums=1, writeQueueNums=1, perm=7, topicSynFlag=0]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new topic registered, TBW102 QueueData [brokerName=broker-a, readQueueNums=8, writeQueueNums=8, perm=7, topicSynFlag=0]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new topic registered, SELF_TEST_TOPIC QueueData [brokerName=broker-a, readQueueNums=1, writeQueueNums=1, perm=6, topicSynFlag=0]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new topic registered, DefaultCluster QueueData [brokerName=broker-a, readQueueNums=16, writeQueueNums=16, perm=7, topicSynFlag=0]
  18:17:30.458 [RemotingExecutorThread_4] INFO  RocketmqNamesrv - new broker registered, 192.168.3.26:10911 HAServer: 192.168.3.26:10912
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  • 妥妥的，原来 RocketMQ Broker 已经启动完成，并且注册到 RocketMQ Namesrv 上。

最后，这是一个 可选 的步骤，命令行中输入 telnet 127.0.0.1 10911 ，看看是否能连接上 RocketMQ Broker 。

5. 启动 RocketMQ Producer

打开 org.apache.rocketmq.example.quickstart.Producer 示例类，代码如下：

// Producer.java

/**
 * This class demonstrates how to send messages to brokers using provided {@link DefaultMQProducer}.
 */
public class Producer {

    public static void main(String[] args) throws MQClientException, InterruptedException {

        /*
         * Instantiate with a producer group name.
         */
        DefaultMQProducer producer = new DefaultMQProducer("please_rename_unique_group_name");

        /*
         * Specify name server addresses.
         * <p/>
         *
         * Alternatively, you may specify name server addresses via exporting environmental variable: NAMESRV_ADDR
         * <pre>
         * {@code
         * producer.setNamesrvAddr("name-server1-ip:9876;name-server2-ip:9876");
         * }
         * </pre>
         */

        /*
         * Launch the instance.
         */
        producer.setNamesrvAddr("127.0.0.1:9876"); // <x> 哈哈哈哈
        producer.start();

        for (int i = 0; i < 1000; i++) {
            try {

                /*
                 * Create a message instance, specifying topic, tag and message body.
                 */
                Message msg = new Message("TopicTest" /* Topic */,
                    "TagA" /* Tag */,
                    ("Hello RocketMQ " + i).getBytes(RemotingHelper.DEFAULT_CHARSET) /* Message body */
                );

                /*
                 * Call send message to deliver message to one of brokers.
                 */
                SendResult sendResult = producer.send(msg);

                System.out.printf("%s%n", sendResult);
            } catch (Exception e) {
                e.printStackTrace();
                Thread.sleep(1000);
            }
        }

        /*
         * Shut down once the producer instance is not longer in use.
         */
        producer.shutdown();
    }

}
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• 注意，在 <x> 哈哈哈哈 处，我们增加了 producer.setNamesrvAddr("127.0.0.1:9876") 代码块，指明 Producer 使用的 RocketMQ Namesrv 。
• :smiling_imp: 可能会有胖友会问，为什么指定的不是 RocketMQ Broker 呢？请退回到。

然后，右键运行，RocketMQ Producer 就启动完成。输出日志如下：

18:22:13.507 [main] DEBUG i.n.u.i.l.InternalLoggerFactory - Using SLF4J as the default logging framework
SendResult [sendStatus=SEND_OK, msgId=C0A8031AE91718B4AAC27A6364050000, offsetMsgId=C0A8031A00002A9F0000000000000000, messageQueue=MessageQueue [topic=TopicTest, brokerName=broker-a, queueId=1], queueOffset=0]
// ... 中间省略 N 条 ... 
SendResult [sendStatus=SEND_OK, msgId=C0A8031AE91718B4AAC27A6369F603E6, offsetMsgId=C0A8031A00002A9F000000000002BD4A, messageQueue=MessageQueue [topic=TopicTest, brokerName=broker-a, queueId=3], queueOffset=249]
SendResult [sendStatus=SEND_OK, msgId=C0A8031AE91718B4AAC27A6369F703E7, offsetMsgId=C0A8031A00002A9F000000000002BDFE, messageQueue=MessageQueue [topic=TopicTest, brokerName=broker-a, queueId=0], queueOffset=249]
18:22:15.558 [NettyClientSelector_1] INFO  RocketmqRemoting - closeChannel: close the connection to remote address[192.168.3.26:10911] result: true
18:22:15.559 [NettyClientSelector_1] INFO  RocketmqRemoting - closeChannel: close the connection to remote address[127.0.0.1:9876] result: true
18:22:15.560 [NettyClientSelector_1] INFO  RocketmqRemoting - closeChannel: close the connection to remote address[192.168.3.26:10909] result: true
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没有最后。

6. 启动 RocketMQ Consumer

打开 org.apache.rocketmq.example.quickstart.Consumer 示例类，代码如下：

// Consumer.java

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.
         * <p/>
         *
         * Alternatively, you may specify name server addresses via exporting environmental variable: NAMESRV_ADDR
         * <pre>
         * {@code
         * consumer.setNamesrvAddr("name-server1-ip:9876;name-server2-ip:9876");
         * }
         * </pre>
         */

        /*
         * Specify where to start in case the specified consumer group is a brand new one.
         */
        consumer.setNamesrvAddr("127.0.0.1:9876"); // <x> 哈哈哈哈
        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");
    }

}
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• 注意，在 <x> 哈哈哈哈 处，我们还增加了 consumer.setNamesrvAddr("127.0.0.1:9876") 代码块，指明 Consumer 使用的 RocketMQ Namesrv 。
• :smiling_imp: 再来一道送命题，为什么指定的不是 RocketMQ Broker 呢？

然后，右键运行，RocketMQ Consumer 就启动完成。输入日志如下：

18:37:12.196 [main] DEBUG i.n.u.i.l.InternalLoggerFactory - Using SLF4J as the default logging framework
Consumer Started.
ConsumeMessageThread_2 Receive New Messages: [MessageExt [queueId=3, storeSize=178, queueOffset=0, sysFlag=0, bornTimestamp=1543054934061, bornHost=/192.168.3.26:64103, storeTimestamp=1543054934065, storeHost=/192.168.3.26:10911, msgId=C0A8031A00002A9F0000000000000164, commitLogOffset=356, bodyCRC=1250039395, reconsumeTimes=0, preparedTransactionOffset=0, toString()=Message{topic='TopicTest', flag=0, properties={MIN_OFFSET=0, MAX_OFFSET=250, CONSUME_START_TIME=1543055832771, UNIQ_KEY=C0A8031AE91718B4AAC27A63642D0002, WAIT=true, TAGS=TagA}, body=[72, 101, 108, 108, 111, 32, 82, 111, 99, 107, 101, 116, 77, 81, 32, 50], transactionId='null'}]] 
ConsumeMessageThread_16 Receive New Messages: [MessageExt [queueId=2, storeSize=179, queueOffset=4, sysFlag=0, bornTimestamp=1543054934102, bornHost=/192.168.3.26:64103, storeTimestamp=1543054934103, storeHost=/192.168.3.26:10911, msgId=C0A8031A00002A9F0000000000000BD9, commitLogOffset=3033, bodyCRC=367242165, reconsumeTimes=0, preparedTransactionOffset=0, toString()=Message{topic='TopicTest', flag=0, properties={MIN_OFFSET=0, MAX_OFFSET=250, CONSUME_START_TIME=1543055832779, UNIQ_KEY=C0A8031AE91718B4AAC27A6364560011, WAIT=true, TAGS=TagA}, body=[72, 101, 108, 108, 111, 32, 82, 111, 99, 107, 101, 116, 77, 81, 32, 49, 55], transactionId='null'}]] 
// ... 中间省略 N 条 ... 
CONSUME_START_TIME=1543055832779, UNIQ_KEY=C0A8031AE91718B4AAC27A636450000F, WAIT=true, TAGS=TagA}, body=[72, 101, 108, 108, 111, 32, 82, 111, 99, 107, 101, 116, 77, 81, 32, 49, 53], transactionId='null'}]] 
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没有最后。