Rocketmq5.0源码阅读 (零) 阅读前的准备

随着Rocketmq5.0的发布, rocketmq-client和rocketmq-spring的适配工作也正在进行中(进度慢被扔到Gsoc了). 为了便于自己理解,将文章记录在此

首先,让我们准备启动文件夹 从rocketmq的distrbution目录下拷贝. store和logs需要新建，为了查看commitlog的移动记录

没错,全都拷过来

修改broker.conf如下

brokerClusterName = DefaultCluster
brokerName = broker-a
brokerId = 0
deleteWhen = 04
fileReservedTime = 48
brokerRole = ASYNC_MASTER
flushDiskType = ASYNC_FLUSH
namesrvAddr = 127.0.0.1:9876
brokerIP1 = 127.0.0.1
autoCreateTopicEnable = true

修改rmq_proxy.json如下

{
  "rocketMQClusterName": "DefaultCluster",
  "namesrvAddr": "localhost:9876"
}

修改plain_acl.yml如下

accounts:
  - accessKey: RocketMQ
    secretKey: 12345678
    whiteRemoteAddress:
    admin: false
    defaultTopicPerm: DENY
    defaultGroupPerm: SUB
    topicPerms:
      - topicA=DENY
      - topicB=PUB|SUB
      - topicC=SUB
    groupPerms:
      # the group should convert to retry topic
      - groupA=DENY
      - groupB=PUB|SUB
      - groupC=SUB

  - accessKey: rocketmq2
    secretKey: 12345678
    whiteRemoteAddress: 192.168.1.*
    # if it is admin, it could access all resources
    admin: true

其次，来到控制台

因为这种方式不是以远程debug加载的, 所以一些类加载不到，也用不了mqadmin的命令,为了更快速调试细节选择了这种做法. 那么要执行创建topic这种操作怎么办呢？也有办法

进入rocketmq-client工程，找到ProducerNormalMessageExample和SimpleConsumerExample两个类，代码替换成如下(代码中的accessKey和secretKey与plain_acl.yml保持一致)

package org.apache.rocketmq.client.java.example;

import java.io.IOException;
import java.net.InetAddress;
import java.nio.charset.StandardCharsets;
import org.apache.rocketmq.client.apis.ClientConfiguration;
import org.apache.rocketmq.client.apis.ClientException;
import org.apache.rocketmq.client.apis.ClientServiceProvider;
import org.apache.rocketmq.client.apis.SessionCredentialsProvider;
import org.apache.rocketmq.client.apis.StaticSessionCredentialsProvider;
import org.apache.rocketmq.client.apis.message.Message;
import org.apache.rocketmq.client.apis.producer.Producer;
import org.apache.rocketmq.client.apis.producer.SendReceipt;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ProducerNormalMessageExample {
    private static final Logger log = LoggerFactory.getLogger(ProducerNormalMessageExample.class);

    private ProducerNormalMessageExample() {
    }

    public static void main(String[] args) throws ClientException, IOException {
        final ClientServiceProvider provider = ClientServiceProvider.loadService();

        // Credential provider is optional for client configuration.
        String accessKey = "rocketmq2";
        String secretKey = "12345678";
        SessionCredentialsProvider sessionCredentialsProvider =
            new StaticSessionCredentialsProvider(accessKey, secretKey);

        //grpc的协议端口
        String ipAddress = InetAddress.getLocalHost().getHostAddress();
        String endpoints = String.format("127.0.0.1:8081");
        ClientConfiguration clientConfiguration = ClientConfiguration.newBuilder()
            .setEndpoints(endpoints)
            .setCredentialProvider(sessionCredentialsProvider)
            .build();
        String topic = "test_topic";
        // In most case, you don't need to create too many producers, singleton pattern is recommended.
        final Producer producer = provider.newProducerBuilder()
            .setClientConfiguration(clientConfiguration)
            // Set the topic name(s), which is optional but recommended. It makes producer could prefetch the topic
            // route before message publishing.
            .setTopics(topic)
            // May throw {@link ClientException} if the producer is not initialized.
            .build();
        // Define your message body.
        byte[] body = "This is a normal message for Apache RocketMQ".getBytes(StandardCharsets.UTF_8);
        String tag = "TagA";
        final Message message = provider.newMessageBuilder()
            // Set topic for the current message.
            .setTopic(topic)
            // Message secondary classifier of message besides topic.
            .setTag(tag)
            // Key(s) of the message, another way to mark message besides message id.
            .setKeys("yourMessageKey-1c151062f96e")
            .setBody(body)
            .build();
        try {
            final SendReceipt sendReceipt = producer.send(message);
            log.info("Send message successfully, messageId={}", sendReceipt.getMessageId());
        } catch (Throwable t) {
            log.error("Failed to send message", t);
        }
        // Close the producer when you don't need it anymore.
        producer.close();
    }
}

package org.apache.rocketmq.client.java.example;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.time.Duration;
import java.util.Collections;
import java.util.List;
import org.apache.rocketmq.client.apis.ClientConfiguration;
import org.apache.rocketmq.client.apis.ClientException;
import org.apache.rocketmq.client.apis.ClientServiceProvider;
import org.apache.rocketmq.client.apis.SessionCredentialsProvider;
import org.apache.rocketmq.client.apis.StaticSessionCredentialsProvider;
import org.apache.rocketmq.client.apis.consumer.FilterExpression;
import org.apache.rocketmq.client.apis.consumer.FilterExpressionType;
import org.apache.rocketmq.client.apis.consumer.SimpleConsumer;
import org.apache.rocketmq.client.apis.message.MessageId;
import org.apache.rocketmq.client.apis.message.MessageView;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class SimpleConsumerExample {
    private static final Logger log = LoggerFactory.getLogger(SimpleConsumerExample.class);

    private SimpleConsumerExample() {
    }

    @SuppressWarnings({"resource", "InfiniteLoopStatement"})
    public static void main(String[] args) throws ClientException, UnknownHostException {
        final ClientServiceProvider provider = ClientServiceProvider.loadService();

        // Credential provider is optional for client configuration.
        String accessKey = "rocketmq2";
        String secretKey = "12345678";
        SessionCredentialsProvider sessionCredentialsProvider =
            new StaticSessionCredentialsProvider(accessKey, secretKey);

        //grpc的协议端口
        String ipAddress = InetAddress.getLocalHost().getHostAddress();
        String endpoints = String.format("%s:8081", ipAddress);
        ClientConfiguration clientConfiguration = ClientConfiguration.newBuilder()
            .setEndpoints(endpoints)
            .setCredentialProvider(sessionCredentialsProvider)
            .build();
        String consumerGroup = "yourConsumerGroup";
        Duration awaitDuration = Duration.ofSeconds(30);
        String tag = "TagA";
        String topic = "test_topic";
        FilterExpression filterExpression = new FilterExpression(tag, FilterExpressionType.TAG);
        SimpleConsumer consumer = provider.newSimpleConsumerBuilder()
            .setClientConfiguration(clientConfiguration)
            // Set the consumer group name.
            .setConsumerGroup(consumerGroup)
            // set await duration for long-polling.
            .setAwaitDuration(awaitDuration)
            // Set the subscription for the consumer.
            .setSubscriptionExpressions(Collections.singletonMap(topic, filterExpression))
            .build();
        // Max message num for each long polling.
        int maxMessageNum = 16;
        // Set message invisible duration after it is received.
        Duration invisibleDuration = Duration.ofSeconds(15);
        // Receive message, multi-threading is more recommended.
        do {
            final List<MessageView> messages = consumer.receive(maxMessageNum, invisibleDuration);
            log.info("Received {} message(s)", messages.size());
            for (MessageView message : messages) {
                final MessageId messageId = message.getMessageId();
                try {
                    consumer.ack(message);
                    log.info("Message is acknowledged successfully, messageId={}", messageId);
                } catch (Throwable t) {
                    log.error("Message is failed to be acknowledged, messageId={}", messageId, t);
                }
            }
        } while (true);
        // Close the simple consumer when you don't need it anymore.
        // consumer.close();
    }
}

OK,开始冒险