在RocketMQ中，使用BrokerStartup作为启动类，相较于NameServer的启动，Broker作为RocketMQ的核心可复杂得多
主函数作为其启动的入口：
public static void main(String[] args) {
start(createBrokerController(args));
}
首先通过createBrokerController方法生成Broker的控制器BrokerController
createBrokerController方法：
public static BrokerController createBrokerController(String[] args) {
System.setProperty(RemotingCommand.REMOTING_VERSION_KEY, Integer.toString(MQVersion.CURRENT_VERSION));
if (null == System.getProperty(NettySystemConfig.COM_ROCKETMQ_REMOTING_SOCKET_SNDBUF_SIZE)) {
NettySystemConfig.socketSndbufSize = 131072;
}
if (null == System.getProperty(NettySystemConfig.COM_ROCKETMQ_REMOTING_SOCKET_RCVBUF_SIZE)) {
NettySystemConfig.socketRcvbufSize = 131072;
}
try {
//PackageConflictDetect.detectFastjson();
Options options = ServerUtil.buildCommandlineOptions(new Options());
commandLine = ServerUtil.parseCmdLine("mqbroker", args, buildCommandlineOptions(options),
new PosixParser());
if (null == commandLine) {
System.exit(-1);
}
final BrokerConfig brokerConfig = new BrokerConfig();
final NettyServerConfig nettyServerConfig = new NettyServerConfig();
final NettyClientConfig nettyClientConfig = new NettyClientConfig();
nettyClientConfig.setUseTLS(Boolean.parseBoolean(System.getProperty(TLS_ENABLE,
String.valueOf(TlsSystemConfig.tlsMode == TlsMode.ENFORCING))));
nettyServerConfig.setListenPort(10911);
final MessageStoreConfig messageStoreConfig = new MessageStoreConfig();
if (BrokerRole.SLAVE == messageStoreConfig.getBrokerRole()) {
int ratio = messageStoreConfig.getAccessMessageInMemoryMaxRatio() - 10;
messageStoreConfig.setAccessMessageInMemoryMaxRatio(ratio);
}
if (commandLine.hasOption('c')) {
String file = commandLine.getOptionValue('c');
if (file != null) {
configFile = file;
InputStream in = new BufferedInputStream(new FileInputStream(file));
properties = new Properties();
properties.load(in);
properties2SystemEnv(properties);
MixAll.properties2Object(properties, brokerConfig);
MixAll.properties2Object(properties, nettyServerConfig);
MixAll.properties2Object(properties, nettyClientConfig);
MixAll.properties2Object(properties, messageStoreConfig);
BrokerPathConfigHelper.setBrokerConfigPath(file);
in.close();
}
}
MixAll.properties2Object(ServerUtil.commandLine2Properties(commandLine), brokerConfig);
if (null == brokerConfig.getRocketmqHome()) {
System.out.printf("Please set the %s variable in your environment to match the location of the RocketMQ installation", MixAll.ROCKETMQ_HOME_ENV);
System.exit(-2);
}
String namesrvAddr = brokerConfig.getNamesrvAddr();
if (null != namesrvAddr) {
try {
String[] addrArray = namesrvAddr.split(";");
for (String addr : addrArray) {
RemotingUtil.string2SocketAddress(addr);
}
} catch (Exception e) {
System.out.printf(
"The Name Server Address[%s] illegal, please set it as follows, \"127.0.0.1:9876;192.168.0.1:9876\"%n",
namesrvAddr);
System.exit(-3);
}
}
switch (messageStoreConfig.getBrokerRole()) {
case ASYNC_MASTER:
case SYNC_MASTER:
brokerConfig.setBrokerId(MixAll.MASTER_ID);
break;
case SLAVE:
if (brokerConfig.getBrokerId() <= 0) {
System.out.printf("Slave's brokerId must be > 0");
System.exit(-3);
}
break;
default:
break;
}
messageStoreConfig.setHaListenPort(nettyServerConfig.getListenPort() + 1);
LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
JoranConfigurator configurator = new JoranConfigurator();
configurator.setContext(lc);
lc.reset();
configurator.doConfigure(brokerConfig.getRocketmqHome() + "/conf/logback_broker.xml");
if (commandLine.hasOption('p')) {
InternalLogger console = InternalLoggerFactory.getLogger(LoggerName.BROKER_CONSOLE_NAME);
MixAll.printObjectProperties(console, brokerConfig);
MixAll.printObjectProperties(console, nettyServerConfig);
MixAll.printObjectProperties(console, nettyClientConfig);
MixAll.printObjectProperties(console, messageStoreConfig);
System.exit(0);
} else if (commandLine.hasOption('m')) {
InternalLogger console = InternalLoggerFactory.getLogger(LoggerName.BROKER_CONSOLE_NAME);
MixAll.printObjectProperties(console, brokerConfig, true);
MixAll.printObjectProperties(console, nettyServerConfig, true);
MixAll.printObjectProperties(console, nettyClientConfig, true);
MixAll.printObjectProperties(console, messageStoreConfig, true);
System.exit(0);
}
log = InternalLoggerFactory.getLogger(LoggerName.BROKER_LOGGER_NAME);
MixAll.printObjectProperties(log, brokerConfig);
MixAll.printObjectProperties(log, nettyServerConfig);
MixAll.printObjectProperties(log, nettyClientConfig);
MixAll.printObjectProperties(log, messageStoreConfig);
final BrokerController controller = new BrokerController(
brokerConfig,
nettyServerConfig,
nettyClientConfig,
messageStoreConfig);
// remember all configs to prevent discard
controller.getConfiguration().registerConfig(properties);
boolean initResult = controller.initialize();
if (!initResult) {
controller.shutdown();
System.exit(-3);
}
Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {
private volatile boolean hasShutdown = false;
private AtomicInteger shutdownTimes = new AtomicInteger(0);
@Override
public void run() {
synchronized (this) {
log.info("Shutdown hook was invoked, {}", this.shutdownTimes.incrementAndGet());
if (!this.hasShutdown) {
this.hasShutdown = true;
long beginTime = System.currentTimeMillis();
controller.shutdown();
long consumingTimeTotal = System.currentTimeMillis() - beginTime;
log.info("Shutdown hook over, consuming total time(ms): {}", consumingTimeTotal);
}
}
}
}, "ShutdownHook"));
return controller;
} catch (Throwable e) {
e.printStackTrace();
System.exit(-1);
}
return null;
}
这里和NameServer中的createNamesrvController方法作用类似，对Broker所需做了一系列的配置
先设置了Netty通信时的缓冲区大小，这里默认是128K
接着会创建了几个实体类
BrokerConfig，用来封装其绝大多数基本配置信息
NettyServerConfig，封装了其作为对外暴露的消息队列服务器的信息
NettyClientConfig，则封装了其作为NameServer客户端的信息
这里面封装的信息和NameServer一个道理，都是映射了配置文件相应的配置
然后对NettyClientConfig的TLS进行设置
让NettyServerConfig默认监听10911端口
紧接着创建了一个MessageStoreConfig，这个就是用来封装Store的信息，
MessageStoreConfig会默认配置BrokerRole为ASYNC_MASTER
Broker有三种身份，用BrokerRole枚举来表示：
public enum BrokerRole {
ASYNC_MASTER,
SYNC_MASTER,
SLAVE;
}
也就是异步Master，同步Master，以及Slave
这里会对其身份进行检查，若是Slave，则需要调整其允许的消息最大内存占比，默认值是40，也就是说Master允许消息最大内存占用40%，而Slave则只允许30%
接着会对”-c“指令进行相应配置的加载
往后看到对namesrvAddr进行了检查，只是简单地检查NameServer集群地址信息是否合法
往下看到有个switch块，其根据Broker的身份，进行设置
只要是Master，将其BrokerId设为0，而Slave的BrokerId需要大于0
（一个Master可以对应多个Slave，但是一个Slave只能对应一个Master，Master与Slave的对应关系通过指定相同的BrokerName，不同的BrokerId来定义，BrokerId为0表示Master，大于0表示Slave，Master也可以部署多个）
继续往下，这里会对Store设置HA的监听端口，是NettyServer侦听端口加1
往下是对“-p”，”-m“指令进行相应配置的加载，以及日志的相关配置
之后就会创建了一个BrokerController：
public BrokerController(
final BrokerConfig brokerConfig,
final NettyServerConfig nettyServerConfig,
final NettyClientConfig nettyClientConfig,
final MessageStoreConfig messageStoreConfig
) {
this.brokerConfig = brokerConfig;
this.nettyServerConfig = nettyServerConfig;
this.nettyClientConfig = nettyClientConfig;
this.messageStoreConfig = messageStoreConfig;
this.consumerOffsetManager = new ConsumerOffsetManager(this);
this.topicConfigManager = new TopicConfigManager(this);
this.pullMessageProcessor = new PullMessageProcessor(this);
this.pullRequestHoldService = new PullRequestHoldService(this);
this.messageArrivingListener = new NotifyMessageArrivingListener(this.pullRequestHoldService);
this.consumerIdsChangeListener = new DefaultConsumerIdsChangeListener(this);
this.consumerManager = new ConsumerManager(this.consumerIdsChangeListener);
this.consumerFilterManager = new ConsumerFilterManager(this);
this.producerManager = new ProducerManager();
this.clientHousekeepingService = new ClientHousekeepingService(this);
this.broker2Client = new Broker2Client(this);
this.subscriptionGroupManager = new SubscriptionGroupManager(this);
this.brokerOuterAPI = new BrokerOuterAPI(nettyClientConfig);
this.filterServerManager = new FilterServerManager(this); this.slaveSynchronize = new SlaveSynchronize(this); this.sendThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getSendThreadPoolQueueCapacity());
this.pullThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getPullThreadPoolQueueCapacity());
this.queryThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getQueryThreadPoolQueueCapacity());
this.clientManagerThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getClientManagerThreadPoolQueueCapacity());
this.consumerManagerThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getConsumerManagerThreadPoolQueueCapacity());
this.heartbeatThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getHeartbeatThreadPoolQueueCapacity());
this.endTransactionThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getEndTransactionPoolQueueCapacity()); this.brokerStatsManager = new BrokerStatsManager(this.brokerConfig.getBrokerClusterName());
this.setStoreHost(new InetSocketAddress(this.getBrokerConfig().getBrokerIP1(), this.getNettyServerConfig().getListenPort())); this.brokerFastFailure = new BrokerFastFailure(this);
this.configuration = new Configuration(
log,
BrokerPathConfigHelper.getBrokerConfigPath(),
this.brokerConfig, this.nettyServerConfig, this.nettyClientConfig, this.messageStoreConfig
);
}
可以看到，这里实例化了许多成员，我就不一一分析，挑几个重要的介绍
ConsumerOffsetManager：用来管理消费者的消费消息的进度，主要通过一张map来缓存
private ConcurrentMap<String/* topic@group */, ConcurrentMap<Integer, Long>> offsetTable =
new ConcurrentHashMap<String, ConcurrentMap<Integer, Long>>(512);
由topic@group的形式构成键，而值中的map的Integer代表具体的哪条消息队列，Long表示该消息队列的偏移量offset
TopicConfigManager：管理Topic和消息队列的信息，主要通过一张map来缓存
private final ConcurrentMap<String, TopicConfig> topicConfigTable =
new ConcurrentHashMap<String, TopicConfig>(1024);
private final DataVersion dataVersion = new DataVersion();
键就是Topic，值TopicConfig用来记录对应的消息队列的个数
PullMessageProcessor、PullRequestHoldService、NotifyMessageArrivingListener这三个来管理Pull消息请求，关于Pull消息在后续博客再细说
ConsumerManager：管理Consumer，主要通过一张map来缓存
private final ConcurrentMap<String/* Group */, ConsumerGroupInfo> consumerTable =
new ConcurrentHashMap<String, ConsumerGroupInfo>(1024);
键值就是Consumer的GroupName，
而ConsumerGroupInfo由如下构成：
private final ConcurrentMap<String/* Topic */, SubscriptionData> subscriptionTable =
new ConcurrentHashMap<String, SubscriptionData>();
private final ConcurrentMap<Channel, ClientChannelInfo> channelInfoTable =
new ConcurrentHashMap<Channel, ClientChannelInfo>(16);
private volatile ConsumeType consumeType;
private volatile MessageModel messageModel;
可以看到封装了一个subscriptionTable ，这个map记录Topic和订阅内容
以及一个channelInfoTable，记录Consumer的物理连接
ConsumeType是一个枚举，表明两种消费方式：
public enum ConsumeType {
CONSUME_ACTIVELY("PULL"),
CONSUME_PASSIVELY("PUSH");
}
MessageModel 也是一个枚举，表明两种消费模式：
public enum MessageModel {
/**
* broadcast
*/
BROADCASTING("BROADCASTING"),
/**
* clustering
*/
CLUSTERING("CLUSTERING");
}
Broadcasting：同一个ConsumerGroup里的每个Consumer都能消费到所订阅Topic的全部消息，也就是一个消息会被多次分发，被多个Consumer消费
Clustering：同一个ConsumerGroup里的每个Consumer只消费所订阅消息的一部分内容，同一个ConsumerGroup里所有的Consumer消费的内容合起来才是所订阅Topic内容的整体，从而达到负载均衡的目的
结合着来看，也就是说使用相同GroupName的一组Consumer，其ConsumeType和MessageModel必定相同，其订阅的Topic会根据ConsumeType和MessageModel来完成相应的方式的消息处理
回到BrokerController的构造
ProducerManager：管理Producer，主要通过一张map来缓存
private final HashMap<String /* group name */, HashMap<Channel, ClientChannelInfo>> groupChannelTable =
new HashMap<String, HashMap<Channel, ClientChannelInfo>>();
相比ConsumerManager，对Producer的管理简单的多，只需要记录group name 和物理连接的映射
再回到createBrokerController方法，在完成BrokerController的创建后，会调用BrokerController的initialize方法：
BrokerController的initialize方法：
public boolean initialize() throws CloneNotSupportedException {
boolean result = this.topicConfigManager.load();
result = result && this.consumerOffsetManager.load();
result = result && this.subscriptionGroupManager.load();
result = result && this.consumerFilterManager.load();
if (result) {
try {
this.messageStore =
new DefaultMessageStore(this.messageStoreConfig, this.brokerStatsManager, this.messageArrivingListener,
this.brokerConfig);
if (messageStoreConfig.isEnableDLegerCommitLog()) {
DLedgerRoleChangeHandler roleChangeHandler = new DLedgerRoleChangeHandler(this, (DefaultMessageStore) messageStore);
((DLedgerCommitLog)((DefaultMessageStore) messageStore).getCommitLog()).getdLedgerServer().getdLedgerLeaderElector().addRoleChangeHandler(roleChangeHandler);
}
this.brokerStats = new BrokerStats((DefaultMessageStore) this.messageStore);
//load plugin
MessageStorePluginContext context = new MessageStorePluginContext(messageStoreConfig, brokerStatsManager, messageArrivingListener, brokerConfig);
this.messageStore = MessageStoreFactory.build(context, this.messageStore);
this.messageStore.getDispatcherList().addFirst(new CommitLogDispatcherCalcBitMap(this.brokerConfig, this.consumerFilterManager));
} catch (IOException e) {
result = false;
log.error("Failed to initialize", e);
}
}
result = result && this.messageStore.load();
if (result) {
this.remotingServer = new NettyRemotingServer(this.nettyServerConfig, this.clientHousekeepingService);
NettyServerConfig fastConfig = (NettyServerConfig) this.nettyServerConfig.clone();
fastConfig.setListenPort(nettyServerConfig.getListenPort() - 2);
this.fastRemotingServer = new NettyRemotingServer(fastConfig, this.clientHousekeepingService);
this.sendMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getSendMessageThreadPoolNums(),
this.brokerConfig.getSendMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.sendThreadPoolQueue,
new ThreadFactoryImpl("SendMessageThread_"));
this.pullMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getPullMessageThreadPoolNums(),
this.brokerConfig.getPullMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.pullThreadPoolQueue,
new ThreadFactoryImpl("PullMessageThread_"));
this.queryMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getQueryMessageThreadPoolNums(),
this.brokerConfig.getQueryMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.queryThreadPoolQueue,
new ThreadFactoryImpl("QueryMessageThread_"));
this.adminBrokerExecutor =
Executors.newFixedThreadPool(this.brokerConfig.getAdminBrokerThreadPoolNums(), new ThreadFactoryImpl(
"AdminBrokerThread_"));
this.clientManageExecutor = new ThreadPoolExecutor(
this.brokerConfig.getClientManageThreadPoolNums(),
this.brokerConfig.getClientManageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.clientManagerThreadPoolQueue,
new ThreadFactoryImpl("ClientManageThread_"));
this.heartbeatExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getHeartbeatThreadPoolNums(),
this.brokerConfig.getHeartbeatThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.heartbeatThreadPoolQueue,
new ThreadFactoryImpl("HeartbeatThread_", true));
this.endTransactionExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getEndTransactionThreadPoolNums(),
this.brokerConfig.getEndTransactionThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.endTransactionThreadPoolQueue,
new ThreadFactoryImpl("EndTransactionThread_"));
this.consumerManageExecutor =
Executors.newFixedThreadPool(this.brokerConfig.getConsumerManageThreadPoolNums(), new ThreadFactoryImpl(
"ConsumerManageThread_"));
this.registerProcessor();
final long initialDelay = UtilAll.computNextMorningTimeMillis() - System.currentTimeMillis();
final long period = 1000 * 60 * 60 * 24;
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.getBrokerStats().record();
} catch (Throwable e) {
log.error("schedule record error.", e);
}
}
}, initialDelay, period, TimeUnit.MILLISECONDS);
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.consumerOffsetManager.persist();
} catch (Throwable e) {
log.error("schedule persist consumerOffset error.", e);
}
}
}, 1000 * 10, this.brokerConfig.getFlushConsumerOffsetInterval(), TimeUnit.MILLISECONDS);
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.consumerFilterManager.persist();
} catch (Throwable e) {
log.error("schedule persist consumer filter error.", e);
}
}
}, 1000 * 10, 1000 * 10, TimeUnit.MILLISECONDS);
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.protectBroker();
} catch (Throwable e) {
log.error("protectBroker error.", e);
}
}
}, 3, 3, TimeUnit.MINUTES);
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.printWaterMark();
} catch (Throwable e) {
log.error("printWaterMark error.", e);
}
}
}, 10, 1, TimeUnit.SECONDS);
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
log.info("dispatch behind commit log {} bytes", BrokerController.this.getMessageStore().dispatchBehindBytes());
} catch (Throwable e) {
log.error("schedule dispatchBehindBytes error.", e);
}
}
}, 1000 * 10, 1000 * 60, TimeUnit.MILLISECONDS);
if (this.brokerConfig.getNamesrvAddr() != null) {
this.brokerOuterAPI.updateNameServerAddressList(this.brokerConfig.getNamesrvAddr());
log.info("Set user specified name server address: {}", this.brokerConfig.getNamesrvAddr());
} else if (this.brokerConfig.isFetchNamesrvAddrByAddressServer()) {
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.brokerOuterAPI.fetchNameServerAddr();
} catch (Throwable e) {
log.error("ScheduledTask fetchNameServerAddr exception", e);
}
}
}, 1000 * 10, 1000 * 60 * 2, TimeUnit.MILLISECONDS);
}
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
if (BrokerRole.SLAVE == this.messageStoreConfig.getBrokerRole()) {
if (this.messageStoreConfig.getHaMasterAddress() != null && this.messageStoreConfig.getHaMasterAddress().length() >= 6) {
this.messageStore.updateHaMasterAddress(this.messageStoreConfig.getHaMasterAddress());
this.updateMasterHAServerAddrPeriodically = false;
} else {
this.updateMasterHAServerAddrPeriodically = true;
}
} else {
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.printMasterAndSlaveDiff();
} catch (Throwable e) {
log.error("schedule printMasterAndSlaveDiff error.", e);
}
}
}, 1000 * 10, 1000 * 60, TimeUnit.MILLISECONDS);
}
}
if (TlsSystemConfig.tlsMode != TlsMode.DISABLED) {
// Register a listener to reload SslContext
try {
fileWatchService = new FileWatchService(
new String[] {
TlsSystemConfig.tlsServerCertPath,
TlsSystemConfig.tlsServerKeyPath,
TlsSystemConfig.tlsServerTrustCertPath
},
new FileWatchService.Listener() {
boolean certChanged, keyChanged = false;
@Override
public void onChanged(String path) {
if (path.equals(TlsSystemConfig.tlsServerTrustCertPath)) {
log.info("The trust certificate changed, reload the ssl context");
reloadServerSslContext();
}
if (path.equals(TlsSystemConfig.tlsServerCertPath)) {
certChanged = true;
}
if (path.equals(TlsSystemConfig.tlsServerKeyPath)) {
keyChanged = true;
}
if (certChanged && keyChanged) {
log.info("The certificate and private key changed, reload the ssl context");
certChanged = keyChanged = false;
reloadServerSslContext();
}
}
private void reloadServerSslContext() {
((NettyRemotingServer) remotingServer).loadSslContext();
((NettyRemotingServer) fastRemotingServer).loadSslContext();
}
});
} catch (Exception e) {
log.warn("FileWatchService created error, can't load the certificate dynamically");
}
}
initialTransaction();
initialAcl();
initialRpcHooks();
}
return result;
}
首先完成对.../store/config/topics.json、.../store/config/consumerOffset.json、
.../store/config/subscriptionGroup.json、.../store/config/consumerFilter.json这几个文件的加载
接着创建一个DefaultMessageStore，这是Broker的核心存储
DefaultMessageStore的构造：
private final ConcurrentMap<String/* topic */, ConcurrentMap<Integer/* queueId */, ConsumeQueue>> consumeQueueTable;
......
public DefaultMessageStore(final MessageStoreConfig messageStoreConfig, final BrokerStatsManager brokerStatsManager,
final MessageArrivingListener messageArrivingListener, final BrokerConfig brokerConfig) throws IOException {
this.messageArrivingListener = messageArrivingListener;
this.brokerConfig = brokerConfig;
this.messageStoreConfig = messageStoreConfig;
this.brokerStatsManager = brokerStatsManager;
// 请求定位服务
this.allocateMappedFileService = new AllocateMappedFileService(this);
// 存储服务
if (messageStoreConfig.isEnableDLegerCommitLog()) {
this.commitLog = new DLedgerCommitLog(this);
} else {
this.commitLog = new CommitLog(this);
}
// 消费队列信息
this.consumeQueueTable = new ConcurrentHashMap<>(32);
// 刷新队列服务
this.flushConsumeQueueService = new FlushConsumeQueueService();
// 清除CommitLog数据服务
this.cleanCommitLogService = new CleanCommitLogService();
// 清除消费队列服务
this.cleanConsumeQueueService = new CleanConsumeQueueService();
this.storeStatsService = new StoreStatsService();
// 索引服务
this.indexService = new IndexService(this); // HA服务，主从复制
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
this.haService = new HAService(this);
} else {
this.haService = null;
}
this.reputMessageService = new ReputMessageService();
this.scheduleMessageService = new ScheduleMessageService(this); this.transientStorePool = new TransientStorePool(messageStoreConfig); if (messageStoreConfig.isTransientStorePoolEnable()) {
this.transientStorePool.init();
} this.allocateMappedFileService.start(); this.indexService.start(); this.dispatcherList = new LinkedList<>();
this.dispatcherList.addLast(new CommitLogDispatcherBuildConsumeQueue());
this.dispatcherList.addLast(new CommitLogDispatcherBuildIndex()); File file = new File(StorePathConfigHelper.getLockFile(messageStoreConfig.getStorePathRootDir()));
MappedFile.ensureDirOK(file.getParent());
lockFile = new RandomAccessFile(file, "rw");
}
可以看到DefaultMessageStore的构造会创建很多服务，来管理store的存储
其中isEnableDLegerCommitLog用来判断是否使用DLeger，默认false是关闭的
所以在默认情况下使用CommitLog + HAService
关于DLeger可参考这篇博客 【Dledger-RocketMQ 基于Raft协议的commitlog存储库】
后续的主从复制还是以CommitLog + HAService为主
回到initialize方法，接着会调用DefaultMessageStore的load方法：
public boolean load() {
boolean result = true;
try {
boolean lastExitOK = !this.isTempFileExist();
log.info("last shutdown {}", lastExitOK ? "normally" : "abnormally");
if (null != scheduleMessageService) {
result = result && this.scheduleMessageService.load();
}
// load Commit Log
result = result && this.commitLog.load();
// load Consume Queue
result = result && this.loadConsumeQueue();
if (result) {
this.storeCheckpoint =
new StoreCheckpoint(StorePathConfigHelper.getStoreCheckpoint(this.messageStoreConfig.getStorePathRootDir()));
this.indexService.load(lastExitOK);
this.recover(lastExitOK);
log.info("load over, and the max phy offset = {}", this.getMaxPhyOffset());
}
} catch (Exception e) {
log.error("load exception", e);
result = false;
}
if (!result) {
this.allocateMappedFileService.shutdown();
}
return result;
}
这里会加载CommitLog和ConsumeQueue对应的文件
接着创建熟悉的NettyRemotingServer，在前面博客中介绍过了，就不再展开
这里会根据nettyServerConfig克隆一份服务端配置，以此创建fastRemotingServer服务端，只不过这个服务端侦听的是上面服务端端口减2的端口号
看过我前面的博客就会发现这个fastRemotingServer的端口号其实就是之前提到过的VIP通道
详见：
接着会根据不同的需求创建很多不同的线程池
然后调用registerProcessor方法：
registerProcessor方法：
public void registerProcessor() {
/**
* SendMessageProcessor
*/
SendMessageProcessor sendProcessor = new SendMessageProcessor(this);
sendProcessor.registerSendMessageHook(sendMessageHookList);
sendProcessor.registerConsumeMessageHook(consumeMessageHookList);
this.remotingServer.registerProcessor(RequestCode.SEND_MESSAGE, sendProcessor, this.sendMessageExecutor);
this.remotingServer.registerProcessor(RequestCode.SEND_MESSAGE_V2, sendProcessor, this.sendMessageExecutor);
this.remotingServer.registerProcessor(RequestCode.SEND_BATCH_MESSAGE, sendProcessor, this.sendMessageExecutor);
this.remotingServer.registerProcessor(RequestCode.CONSUMER_SEND_MSG_BACK, sendProcessor, this.sendMessageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.SEND_MESSAGE, sendProcessor, this.sendMessageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.SEND_MESSAGE_V2, sendProcessor, this.sendMessageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.SEND_BATCH_MESSAGE, sendProcessor, this.sendMessageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.CONSUMER_SEND_MSG_BACK, sendProcessor, this.sendMessageExecutor);
/**
* PullMessageProcessor
*/
this.remotingServer.registerProcessor(RequestCode.PULL_MESSAGE, this.pullMessageProcessor, this.pullMessageExecutor);
this.pullMessageProcessor.registerConsumeMessageHook(consumeMessageHookList);
/**
* QueryMessageProcessor
*/
NettyRequestProcessor queryProcessor = new QueryMessageProcessor(this);
this.remotingServer.registerProcessor(RequestCode.QUERY_MESSAGE, queryProcessor, this.queryMessageExecutor);
this.remotingServer.registerProcessor(RequestCode.VIEW_MESSAGE_BY_ID, queryProcessor, this.queryMessageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.QUERY_MESSAGE, queryProcessor, this.queryMessageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.VIEW_MESSAGE_BY_ID, queryProcessor, this.queryMessageExecutor);
/**
* ClientManageProcessor
*/
ClientManageProcessor clientProcessor = new ClientManageProcessor(this);
this.remotingServer.registerProcessor(RequestCode.HEART_BEAT, clientProcessor, this.heartbeatExecutor);
this.remotingServer.registerProcessor(RequestCode.UNREGISTER_CLIENT, clientProcessor, this.clientManageExecutor);
this.remotingServer.registerProcessor(RequestCode.CHECK_CLIENT_CONFIG, clientProcessor, this.clientManageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.HEART_BEAT, clientProcessor, this.heartbeatExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.UNREGISTER_CLIENT, clientProcessor, this.clientManageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.CHECK_CLIENT_CONFIG, clientProcessor, this.clientManageExecutor);
/**
* ConsumerManageProcessor
*/
ConsumerManageProcessor consumerManageProcessor = new ConsumerManageProcessor(this);
this.remotingServer.registerProcessor(RequestCode.GET_CONSUMER_LIST_BY_GROUP, consumerManageProcessor, this.consumerManageExecutor);
this.remotingServer.registerProcessor(RequestCode.UPDATE_CONSUMER_OFFSET, consumerManageProcessor, this.consumerManageExecutor);
this.remotingServer.registerProcessor(RequestCode.QUERY_CONSUMER_OFFSET, consumerManageProcessor, this.consumerManageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.GET_CONSUMER_LIST_BY_GROUP, consumerManageProcessor, this.consumerManageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.UPDATE_CONSUMER_OFFSET, consumerManageProcessor, this.consumerManageExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.QUERY_CONSUMER_OFFSET, consumerManageProcessor, this.consumerManageExecutor);
/**
* EndTransactionProcessor
*/
this.remotingServer.registerProcessor(RequestCode.END_TRANSACTION, new EndTransactionProcessor(this), this.endTransactionExecutor);
this.fastRemotingServer.registerProcessor(RequestCode.END_TRANSACTION, new EndTransactionProcessor(this), this.endTransactionExecutor);
/**
* Default
*/
AdminBrokerProcessor adminProcessor = new AdminBrokerProcessor(this);
this.remotingServer.registerDefaultProcessor(adminProcessor, this.adminBrokerExecutor);
this.fastRemotingServer.registerDefaultProcessor(adminProcessor, this.adminBrokerExecutor);
}
这里会创建好几种Processor，通过registerProcessor方法同时注册到remotingServer和fastRemotingServer中
registerProcessor方法：
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);
}
这里实际上就是向processorTable进行了记录的添加，为的是后续收到请求能做出对应的处理
processorTable：
protected final HashMap<Integer/* request code */, Pair<NettyRequestProcessor, ExecutorService>> processorTable =
new HashMap<Integer, Pair<NettyRequestProcessor, ExecutorService>>(64);
这里的SendMessageProcessor很重要，后续会详细介绍
在完成registerProcessor后，会创建8个定时任务
①
BrokerController.this.getBrokerStats().record();
定时打印Broker的状态
②
BrokerController.this.consumerOffsetManager.persist();
定时向consumerOffset.json文件中写入消费者偏移量
③
BrokerController.this.consumerFilterManager.persist();
定时向consumerFilter.json文件写入消费者过滤器信息
④
BrokerController.this.protectBroker();
定时禁用消费慢的consumer，保护Broker，需要设置disableConsumeIfConsumerReadSlowly属性，默认false
⑤
BrokerController.this.printWaterMark();
定时打印Send、Pull、Query、Transaction队列信息
⑥
public void run() {
try {
log.info("dispatch behind commit log {} bytes", BrokerController.this.getMessageStore().dispatchBehindBytes());
} catch (Throwable e) {
log.error("schedule dispatchBehindBytes error.", e);
}
}
定时打印已存储在提交日志中但尚未调度到消费队列的字节数
⑦
if (this.brokerConfig.getNamesrvAddr() != null) {
this.brokerOuterAPI.updateNameServerAddressList(this.brokerConfig.getNamesrvAddr());
log.info("Set user specified name server address: {}", this.brokerConfig.getNamesrvAddr());
} else if (this.brokerConfig.isFetchNamesrvAddrByAddressServer()) {
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.brokerOuterAPI.fetchNameServerAddr();
} catch (Throwable e) {
log.error("ScheduledTask fetchNameServerAddr exception", e);
}
}
}, 1000 * 10, 1000 * 60 * 2, TimeUnit.MILLISECONDS);
}
若是设置了NamesrvAddr，需要通过updateNameServerAddressList完成一次NameServer地址的跟新（updateNameServerAddressList在前面博客介绍过了）
若是设置了NamesrvAddr，并且设置了fetchNamesrvAddrByAddressServer属性（默认关闭），需要定时获取更新NameServer地址（fetchNameServerAddr方法在之前博客也介绍过）
⑧
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
if (BrokerRole.SLAVE == this.messageStoreConfig.getBrokerRole()) {
if (this.messageStoreConfig.getHaMasterAddress() != null && this.messageStoreConfig.getHaMasterAddress().length() >= 6) {
this.messageStore.updateHaMasterAddress(this.messageStoreConfig.getHaMasterAddress());
this.updateMasterHAServerAddrPeriodically = false;
} else {
this.updateMasterHAServerAddrPeriodically = true;
}
} else {
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
BrokerController.this.printMasterAndSlaveDiff();
} catch (Throwable e) {
log.error("schedule printMasterAndSlaveDiff error.", e);
}
}
}, 1000 * 10, 1000 * 60, TimeUnit.MILLISECONDS);
}
}
在非DLeger模式下
若是SLAVE，则需要检查是否设置了HA的Master地址
若设置了Master地址要通过updateHaMasterAddress方法向更新Master地址
updateHaMasterAddress方法实则是在HAClient中实现的：
public void updateMasterAddress(final String newAddr) {
String currentAddr = this.masterAddress.get();
if (currentAddr == null || !currentAddr.equals(newAddr)) {
this.masterAddress.set(newAddr);
log.info("update master address, OLD: " + currentAddr + " NEW: " + newAddr);
}
}
非常简单，只是一个比较替换的操作
若没有设置需要更改updateMasterHAServerAddrPeriodically为true，在后面会有用
若是MASTER，则需要定时打印slave落后的字节数
设置完定时任务后，和NameServer中一样设置了对SslContext的监听
接着通过initialTransaction方法，加载事务需要的实例
initialTransaction方法：
private void initialTransaction() {
this.transactionalMessageService = ServiceProvider.loadClass(ServiceProvider.TRANSACTION_SERVICE_ID, TransactionalMessageService.class);
if (null == this.transactionalMessageService) {
this.transactionalMessageService = new TransactionalMessageServiceImpl(new TransactionalMessageBridge(this, this.getMessageStore()));
log.warn("Load default transaction message hook service: {}", TransactionalMessageServiceImpl.class.getSimpleName());
}
this.transactionalMessageCheckListener = ServiceProvider.loadClass(ServiceProvider.TRANSACTION_LISTENER_ID, AbstractTransactionalMessageCheckListener.class);
if (null == this.transactionalMessageCheckListener) {
this.transactionalMessageCheckListener = new DefaultTransactionalMessageCheckListener();
log.warn("Load default discard message hook service: {}", DefaultTransactionalMessageCheckListener.class.getSimpleName());
}
this.transactionalMessageCheckListener.setBrokerController(this);
this.transactionalMessageCheckService = new TransactionalMessageCheckService(this);
}
这里动态加载了TransactionalMessageService和AbstractTransactionalMessageCheckListener的实现类，位于如下
"META-INF/service/org.apache.rocketmq.broker.transaction.TransactionalMessageService"
"META-INF/service/org.apache.rocketmq.broker.transaction.AbstractTransactionalMessageCheckListener"
还创建了TransactionalMessageCheckService
initialAcl会创建ACL权限检查：
private void initialAcl() {
if (!this.brokerConfig.isAclEnable()) {
log.info("The broker dose not enable acl");
return;
}
List<AccessValidator> accessValidators = ServiceProvider.load(ServiceProvider.ACL_VALIDATOR_ID, AccessValidator.class);
if (accessValidators == null || accessValidators.isEmpty()) {
log.info("The broker dose not load the AccessValidator");
return;
}
for (AccessValidator accessValidator: accessValidators) {
final AccessValidator validator = accessValidator;
this.registerServerRPCHook(new RPCHook() {
@Override
public void doBeforeRequest(String remoteAddr, RemotingCommand request) {
//Do not catch the exception
validator.validate(validator.parse(request, remoteAddr));
}
@Override
public void doAfterResponse(String remoteAddr, RemotingCommand request, RemotingCommand response) {
}
});
}
}
需要设置aclEnable属性，默认关闭
若是设置了，同样会加载"META-INF/service/org.apache.rocketmq.acl.AccessValidator"配置的AccessValidator实体类
然后将其包装成RPC钩子，注册到remotingServer和fastRemotingServer中，用于请求的调用validate方法进行ACL权限检查
initialRpcHooks方法则会注册配置了的RPC钩子：
private void initialRpcHooks() {
List<RPCHook> rpcHooks = ServiceProvider.load(ServiceProvider.RPC_HOOK_ID, RPCHook.class);
if (rpcHooks == null || rpcHooks.isEmpty()) {
return;
}
for (RPCHook rpcHook: rpcHooks) {
this.registerServerRPCHook(rpcHook);
}
}
加载"META-INF/service/org.apache.rocketmq.remoting.RPCHook"下的配置的实体类
到此Broker启动前的准备工作已经完成，后面start方法会进行真正的启动，在下一篇博客继续分析