Broker主要负责消息的存储、投递和查询以及服务高可用保证, Broker包含了以下几个重要子模块。
该方法将会创建并且初始化一个BrokerController实例
createBrokerController创建BrokerController: 解析命令行, 加载Broker配置, NettyServer配置, NettyClient配置, 并保持, 然后进行一些配置的校验, 日志的配置, 然后创建一个BrokerController实例。
BrokerController相当于Broker的一个中央控制器类, 创建了BrokerController实例后, 执行initialize方法进行初始化操作。
public static BrokerController createBrokerController(String[] args) {
//设置RocketMQ的版本信息,设置属性rocketmq.remoting.version,即当前rocketmq版本
System.setProperty(RemotingCommand.REMOTING_VERSION_KEY, Integer.toString(MQVersion.CURRENT_VERSION));
try {
//PackageConflictDetect.detectFastjson();
/*
* 1 jar包启动时,构建命令行操作的指令,使用main方法启动可以忽略
*/
Options options = ServerUtil.buildCommandlineOptions(new Options());
//mqbroker命令文件
commandLine = ServerUtil.parseCmdLine("mqbroker", args, buildCommandlineOptions(options),
new PosixParser());
if (null == commandLine) {
System.exit(-1);
}
/*
* 2 创建broker的配置类
*/
//创建Broker的配置类,包含Broker的各种配置,比如ROCKETMQ_HOME
final BrokerConfig brokerConfig = new BrokerConfig();
//NettyServer的配置类,Broker作为服务端,比如接收来自客户端的消息的时候
final NettyServerConfig nettyServerConfig = new NettyServerConfig();
//NettyClient的配置类,Broker还会作为客户端,比如连接NameServer的时候
final NettyClientConfig nettyClientConfig = new NettyClientConfig();
// tls安全相关配置
nettyClientConfig.setUseTLS(Boolean.parseBoolean(System.getProperty(TLS_ENABLE,
String.valueOf(TlsSystemConfig.tlsMode == TlsMode.ENFORCING))));
//设置作为NettyServer时的监听端口为10911
nettyServerConfig.setListenPort(10911);
//Broker的消息存储配置,例如各种文件大小等
final MessageStoreConfig messageStoreConfig = new MessageStoreConfig();
//如果broker的角色是slave,设置命中消息在内存的最大比例
//默认broker角色是异步master
if (BrokerRole.SLAVE == messageStoreConfig.getBrokerRole()) {
//30
int ratio = messageStoreConfig.getAccessMessageInMemoryMaxRatio() - 10;
messageStoreConfig.setAccessMessageInMemoryMaxRatio(ratio);
}
/*
* 3 解析外部配置文件
* 判断命令行中是否包含字符'c',即是否包含通过命令行指定配置文件的命令
* 例如,启动Broker的时候添加的 -c /Volumes/Samsung/Idea/rocketmq/config/conf/broker.conf命令
*/
if (commandLine.hasOption('c')) {
//获取该命令指定的配置文件
String file = commandLine.getOptionValue('c');
if (file != null) {
//加载外部配置文件
configFile = file;
InputStream in = new BufferedInputStream(new FileInputStream(file));
properties = new Properties();
properties.load(in);
//将rmqAddressServerDomain、rmqAddressServerSubGroup属性设置为系统属性
properties2SystemEnv(properties);
//设置broker的配置信息
MixAll.properties2Object(properties, brokerConfig);
//设置nettyServer的配置信息
MixAll.properties2Object(properties, nettyServerConfig);
//设置nettyClient的配置信息
MixAll.properties2Object(properties, nettyClientConfig);
//设置messageStore的配置信息
MixAll.properties2Object(properties, messageStoreConfig);
//设置配置文件路径
BrokerPathConfigHelper.setBrokerConfigPath(file);
in.close();
}
}
//设置broker的配置信息
MixAll.properties2Object(ServerUtil.commandLine2Properties(commandLine), brokerConfig);
//如果不存在ROCKETMQ_HOME的配置,那么打印异常并退出程序
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);
}
/*
* 4 获取namesrvAddr,即NameServer的地址,并进行校验
*/
String namesrvAddr = brokerConfig.getNamesrvAddr();
if (null != namesrvAddr) {
try {
//拆分NameServer的地址
//可以指定多个NameServer的地址,以";"分隔
String[] addrArray = namesrvAddr.split(";");
//将字符串的地址,转换为网络连接的SocketAddress,检测格式是否正确
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);
}
}
/*
* 4 设置、校验brokerId
*
* 根据broker的角色配置brokerId,默认角色是ASYNC_MASTER
* 通过此配置可知BrokerId为0表示Master,非0表示Slave
*/
switch (messageStoreConfig.getBrokerRole()) {
case ASYNC_MASTER:
case SYNC_MASTER:
//如果是master角色,那么设置brokerId为0
brokerConfig.setBrokerId(MixAll.MASTER_ID);
break;
case SLAVE:
//如果是slave角色,需要brokerId大于0
if (brokerConfig.getBrokerId() <= 0) {
System.out.printf("Slave's brokerId must be > 0");
System.exit(-3);
}
break;
default:
break;
}
// 开启 DLeger 的操作
if (messageStoreConfig.isEnableDLegerCommitLog()) {
brokerConfig.setBrokerId(-1);
}
/*
* 5 设置高可用通信监听端口,为监听端口+1,默认就是10912
* 该端口主要用于比如主从同步之类的高可用操作
*
* 在配置broker集群的时候需要注意,配置集群时可能会抛出:Address already in use
* 因为一个broker机器会占用三个端口,监听ip端口,以及监听ip端口+1的端口,监听ip端口-2端口
*/
messageStoreConfig.setHaListenPort(nettyServerConfig.getListenPort() + 1);
/*
* 6 日志相关配置
*/
LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory();
//Joran 是 logback 使用的一个配置加载库,可以直接调用JoranConfigurator类重新实现logback的配置机制,
JoranConfigurator configurator = new JoranConfigurator();
configurator.setContext(lc);
lc.reset();
//配置broker日志文件的路徑
System.setProperty("brokerLogDir", "");
//isolateLogEnable属性表示在同一台机器上部署多个broker时是否区分日志路径,默認false
if (brokerConfig.isIsolateLogEnable()) {
System.setProperty("brokerLogDir", brokerConfig.getBrokerName() + "_" + brokerConfig.getBrokerId());
}
if (brokerConfig.isIsolateLogEnable() && messageStoreConfig.isEnableDLegerCommitLog()) {
System.setProperty("brokerLogDir", brokerConfig.getBrokerName() + "_" + messageStoreConfig.getdLegerSelfId());
}
configurator.doConfigure(brokerConfig.getRocketmqHome() + "/conf/logback_broker.xml");
/*判断命令行中是否包含字符'p'(printConfigItem)和'm',如果存在则打印配置信息并结束jvm运行,没有的话就不用管*/
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);
}
//打印当前broker的配置日志
log = InternalLoggerFactory.getLogger(LoggerName.BROKER_LOGGER_NAME);
MixAll.printObjectProperties(log, brokerConfig);
MixAll.printObjectProperties(log, nettyServerConfig);
MixAll.printObjectProperties(log, nettyClientConfig);
MixAll.printObjectProperties(log, messageStoreConfig);
/*
* 7 实例化BrokerController,设置各种属性
*/
final BrokerController controller = new BrokerController(
brokerConfig,
nettyServerConfig,
nettyClientConfig,
messageStoreConfig);
// 将所有的-c的外部配置信息保存到NamesrvController中的Configuration对象属性的allConfigs属性中
controller.getConfiguration().registerConfig(properties);
/*
* 8 初始化BrokerController
* 创建netty远程服务,初始化Netty线程池,注册请求处理器,配置定时任务,用于扫描并移除不活跃的Broker等操作。
*/
boolean initResult = controller.initialize();
//初始化失败则退出
if (!initResult) {
controller.shutdown();
System.exit(-3);
}
/*
* 9 添加关闭钩子方法,在Broker关闭之前执行,进行一些内存清理、对象销毁等操作
*/
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();
//执行controller的shutdown方法,并且还会在messageStore#shutdown方法中将abort临时文件删除。
controller.shutdown();
long consumingTimeTotal = System.currentTimeMillis() - beginTime;
log.info("Shutdown hook over, consuming total time(ms): {}", consumingTimeTotal);
}
}
}
}, "ShutdownHook"));
//返回BrokerController
return controller;
} catch (Throwable e) {
e.printStackTrace();
System.exit(-1);
}
return null;
}
设置了配置信息之后, 会进行一系列校验:
BrokerController的构造器实际上同样是在进行一系列的赋值和初始化操作, 创建各种manager和queue组件, 组件角色之间的互动是通过BrokerController完成的, 不是组件直接完成的。
public BrokerController(
final BrokerConfig brokerConfig,
final NettyServerConfig nettyServerConfig,
final NettyClientConfig nettyClientConfig,
final MessageStoreConfig messageStoreConfig
) {
//broker的配置
this.brokerConfig = brokerConfig;
//作为netty服务端与客户端交互的配置
this.nettyServerConfig = nettyServerConfig;
//作为netty客户端与服务端交互的配置
this.nettyClientConfig = nettyClientConfig;
//消息存储的配置
this.messageStoreConfig = messageStoreConfig;
//消费者偏移量管理器,维护offset进度信息
this.consumerOffsetManager = messageStoreConfig.isEnableLmq() ? new LmqConsumerOffsetManager(this) : new ConsumerOffsetManager(this);
//topic配置管理器,管理broker中存储的所有topic的配置
this.topicConfigManager = messageStoreConfig.isEnableLmq() ? new LmqTopicConfigManager(this) : new TopicConfigManager(this);
//拉取消息处理器,用于处理拉取消息的请求
this.pullMessageProcessor = new PullMessageProcessor(this);
//拉取请求挂起服务,处理无消息时push长轮询消费者的挂起等待机制
this.pullRequestHoldService = messageStoreConfig.isEnableLmq() ? new LmqPullRequestHoldService(this) : new PullRequestHoldService(this);
//消息送达的监听器,生产者消息到达时通过该监听器触发pullRequestHoldService通知pullRequestHoldService
this.messageArrivingListener = new NotifyMessageArrivingListener(this.pullRequestHoldService);
//消费者id变化监听器
this.consumerIdsChangeListener = new DefaultConsumerIdsChangeListener(this);
//消费者管理类,维护消费者组的注册实例信息以及topic的订阅信息,并对消费者id变化进行监听
this.consumerManager = new ConsumerManager(this.consumerIdsChangeListener);
//消费者过滤管理器,配置文件为:xx/config/consumerFilter.json
this.consumerFilterManager = new ConsumerFilterManager(this);
//生产者管理器,包含生产者的注册信息,通过groupName分组
this.producerManager = new ProducerManager();
//客户端连接心跳服务,用于定时扫描生产者和消费者客户端,并将不活跃的客户端通道及相关信息移除
this.clientHousekeepingService = new ClientHousekeepingService(this);
//处理某些broker到客户端的请求,例如检查生产者的事务状态,重置offset
this.broker2Client = new Broker2Client(this);
//订阅分组关系管理器,维护消费者组的一些附加运维信息
this.subscriptionGroupManager = messageStoreConfig.isEnableLmq() ? new LmqSubscriptionGroupManager(this) : new SubscriptionGroupManager(this);
//broker对方访问的API,处理broker对外的发起请求,比如向nameServer注册,向master、slave发起的请求
this.brokerOuterAPI = new BrokerOuterAPI(nettyClientConfig);
//过滤服务管理器,拉取消息过滤
this.filterServerManager = new FilterServerManager(this);
//用于从节点,定时向主节点发起请求同步数据,例如topic配置、消费位移等
this.slaveSynchronize = new SlaveSynchronize(this);
/*初始化各种阻塞队列。将会被设置到对应的处理不同客户端请求的线程池执行器中*/
//处理来自生产者的发送消息的请求的队列
this.sendThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getSendThreadPoolQueueCapacity());
//https://github.com/apache/rocketmq/pull/3631
this.putThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getPutThreadPoolQueueCapacity());
//处理来自消费者的拉取消息的请求的队列
this.pullThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getPullThreadPoolQueueCapacity());
//处理reply消息的请求的队列,RocketMQ4.7.0版本中增加了request-reply新特性,该特性允许producer在发送消息后同步或者异步等待consumer消费完消息并返回响应消息,类似rpc调用效果。
//即生产者发送了消息之后,可以同步或者异步的收到消费了这条消息的消费者的响应
this.replyThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getReplyThreadPoolQueueCapacity());
//处理查询请求的队列
this.queryThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getQueryThreadPoolQueueCapacity());
//客户端管理器的队列
this.clientManagerThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getClientManagerThreadPoolQueueCapacity());
//消费者管理器的队列,目前没用到
this.consumerManagerThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getConsumerManagerThreadPoolQueueCapacity());
//心跳处理的队列
this.heartbeatThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getHeartbeatThreadPoolQueueCapacity());
//事务消息相关处理的队列
this.endTransactionThreadPoolQueue = new LinkedBlockingQueue<Runnable>(this.brokerConfig.getEndTransactionPoolQueueCapacity());
//broker状态管理器,保存Broker运行时状态
this.brokerStatsManager = messageStoreConfig.isEnableLmq() ? new LmqBrokerStatsManager(this.brokerConfig.getBrokerClusterName(), this.brokerConfig.isEnableDetailStat()) : new BrokerStatsManager(this.brokerConfig.getBrokerClusterName(), this.brokerConfig.isEnableDetailStat());
//目前没用到
this.setStoreHost(new InetSocketAddress(this.getBrokerConfig().getBrokerIP1(), this.getNettyServerConfig().getListenPort()));
//broker快速失败服务
this.brokerFastFailure = new BrokerFastFailure(this);
//配置类
this.configuration = new Configuration(
log,
BrokerPathConfigHelper.getBrokerConfigPath(),
this.brokerConfig, this.nettyServerConfig, this.nettyClientConfig, this.messageStoreConfig
);
}
创建broker控制器以后, 需要进行broker的初始化
大致过程:
public boolean initialize() throws CloneNotSupportedException {
/*
* 1 加载配置文件
* 尝试从json配置文件或者bak备份文件中加载json字符串,然后反序列化转换为自身内部的属性
*/
//topic配置文件加载,路径为 {user.home}/store/config/topics.json
boolean result = this.topicConfigManager.load();
//消费者消费偏移量配置文件加载,路径为 {user.home}/store/config/consumerOffset.json
result = result && this.consumerOffsetManager.load();
//订阅分组配置文件加载,路径为 {user.home}/store/config/subscriptionGroup.json
result = result && this.subscriptionGroupManager.load();
//消费者过滤配置文件加载,路径为 {user.home}/store/config/consumerFilter.json
result = result && this.consumerFilterManager.load();
/*
* 如果上一步加载配置全部成功
* 2 实例化和初始化消息存储服务相关类DefaultMessageStore
*/
if (result) {
try {
//实例化消息存储类DefaultMessageStore
this.messageStore =
new DefaultMessageStore(this.messageStoreConfig, this.brokerStatsManager, this.messageArrivingListener,
this.brokerConfig);
//如果启动了enableDLegerCommitLog,就创建DLeger组件DLedgerRoleChangeHandler。默认为false,如果需要开启则该值需要设置为true。
//在启用enableDLegerCommitLog情况下,broker通过raft协议选主,可以实现主从角色自动切换,这是4.5版本之后的新功能
//简单的说,如果启动enableDLegerCommitLog,就表示启用 RocketMQ 的容灾机制——自动主从切换,
if (messageStoreConfig.isEnableDLegerCommitLog()) {
DLedgerRoleChangeHandler roleChangeHandler = new DLedgerRoleChangeHandler(this, (DefaultMessageStore) messageStore);
((DLedgerCommitLog) ((DefaultMessageStore) messageStore).getCommitLog()).getdLedgerServer().getdLedgerLeaderElector().addRoleChangeHandler(roleChangeHandler);
}
//broker的统计服务类,保存了broker的一些统计数据
//例如msgPutTotalTodayNow --现在存储的消息数量,msgPutTotalTodayMorning --今天存储的消息数量
this.brokerStats = new BrokerStats((DefaultMessageStore) this.messageStore);
//load plugin
//加载存在的消息存储插件,不必深究
MessageStorePluginContext context = new MessageStorePluginContext(messageStoreConfig, brokerStatsManager, messageArrivingListener, brokerConfig);
this.messageStore = MessageStoreFactory.build(context, this.messageStore);
//添加一个针对布隆过滤器的消费过滤类
this.messageStore.getDispatcherList().addFirst(new CommitLogDispatcherCalcBitMap(this.brokerConfig, this.consumerFilterManager));
} catch (IOException e) {
result = false;
log.error("Failed to initialize", e);
}
}
/*
* 如果上一步加载配置全部成功
* 3 通过消息存储服务加载消息存储的相关文件,比如commitLog日志文件、consumequeue消息消费队列文件的加载,indexFile索引文件的构建
* messageStore还会将这些文件的内容加载到内存中,并且完成RocketMQ的数据恢复
* 这是核broker启动的心步骤之一
*/
result = result && this.messageStore.load();
/*
* 如果上一步加载配置全部成功
* 3 开始初始化Broker通信层和各种请求执行器
*/
if (result) {
/*
* 4 创建netty远程服务,remotingServer和fastRemotingServer
*/
//创建broker的netty远程服务,端口为10911,可以用于处理客户端的所有请求。
this.remotingServer = new NettyRemotingServer(this.nettyServerConfig, this.clientHousekeepingService);
//创建一个broker的netty快速远程服务的配置
NettyServerConfig fastConfig = (NettyServerConfig) this.nettyServerConfig.clone();
//设置快速netty远程服务的配置监听的端口号为普通服务的端口-2,默认10909
fastConfig.setListenPort(nettyServerConfig.getListenPort() - 2);
//创建broker的netty快速服务,这就是所谓的快速通道,对应可以处理客户端除了拉取消息之外的所有请求,所谓的VIP端口。
this.fastRemotingServer = new NettyRemotingServer(fastConfig, this.clientHousekeepingService);
/*
* 5 创建各种执行器线程池
*/
//处理发送消息的请求的线程池
this.sendMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getSendMessageThreadPoolNums(),
this.brokerConfig.getSendMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.sendThreadPoolQueue,
new ThreadFactoryImpl("SendMessageThread_"));
///https://github.com/apache/rocketmq/pull/3631
this.putMessageFutureExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getPutMessageFutureThreadPoolNums(),
this.brokerConfig.getPutMessageFutureThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.putThreadPoolQueue,
new ThreadFactoryImpl("PutMessageThread_"));
//处理拉取消息的请求的线程池
this.pullMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getPullMessageThreadPoolNums(),
this.brokerConfig.getPullMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.pullThreadPoolQueue,
new ThreadFactoryImpl("PullMessageThread_"));
//处理reply消息的请求的线程池
this.replyMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getProcessReplyMessageThreadPoolNums(),
this.brokerConfig.getProcessReplyMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.replyThreadPoolQueue,
new ThreadFactoryImpl("ProcessReplyMessageThread_"));
//处理查询请求的线程池
this.queryMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getQueryMessageThreadPoolNums(),
this.brokerConfig.getQueryMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.queryThreadPoolQueue,
new ThreadFactoryImpl("QueryMessageThread_"));
//broker 管理线程池,作为默认处理器的线程池
this.adminBrokerExecutor =
Executors.newFixedThreadPool(this.brokerConfig.getAdminBrokerThreadPoolNums(), new ThreadFactoryImpl(
"AdminBrokerThread_"));
//客户端管理器的线程池
this.clientManageExecutor = new ThreadPoolExecutor(
this.brokerConfig.getClientManageThreadPoolNums(),
this.brokerConfig.getClientManageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.clientManagerThreadPoolQueue,
new ThreadFactoryImpl("ClientManageThread_"));
//心跳处理的线程池
this.heartbeatExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getHeartbeatThreadPoolNums(),
this.brokerConfig.getHeartbeatThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.heartbeatThreadPoolQueue,
new ThreadFactoryImpl("HeartbeatThread_", true));
//事务消息相关处理的线程池
this.endTransactionExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getEndTransactionThreadPoolNums(),
this.brokerConfig.getEndTransactionThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.endTransactionThreadPoolQueue,
new ThreadFactoryImpl("EndTransactionThread_"));
//消费者管理的线程池
this.consumerManageExecutor =
Executors.newFixedThreadPool(this.brokerConfig.getConsumerManageThreadPoolNums(), new ThreadFactoryImpl(
"ConsumerManageThread_"));
/*
* 6 注册处理器
*/
this.registerProcessor();
/*
* 7 启动一系列定时周期任务
*/
final long initialDelay = UtilAll.computeNextMorningTimeMillis() - System.currentTimeMillis();
//每隔24h打印昨天生产和消费的消息数量
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);
//每隔5s將消费者offset进行持久化,存入consumerOffset.json文件中
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);
//每隔10s將消费过滤信息进行持久化,存入consumerFilter.json文件中
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);
//每隔3m將检查消费者的消费进度
//当消费进度落后阈值的时候,并且disableConsumeIfConsumerReadSlowly=true(默认false),就停止消费者消费,保护broker,避免消费积压
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);
//每隔1s將打印发送消息线程池队列、拉取消息线程池队列、查询消息线程池队列、结束事务线程池队列的大小以及队列头部元素存在时间
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);
//每隔1m將打印已存储在commitlog提交日志中但尚未分派到consume queue消费队列的字节数。
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);
//如果broker的nameServer地址不为null
if (this.brokerConfig.getNamesrvAddr() != null) {
//更新nameServer地址
this.brokerOuterAPI.updateNameServerAddressList(this.brokerConfig.getNamesrvAddr());
log.info("Set user specified name server address: {}", this.brokerConfig.getNamesrvAddr());
} else if (this.brokerConfig.isFetchNamesrvAddrByAddressServer()) {
//如果没有指定nameServer地址,并且允许从地址服务器获取nameServer地址
//那么每隔2m从nameServer地址服务器拉取最新的nameServer地址并更新
//要想动态更新nameServer地址,需要指定一个地址服务器的url,并且fetchNamesrvAddrByAddressServer设置为true
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);
}
//如果没有开启DLeger服务,DLeger开启后表示支持高可用的主从自动切换
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
//如果当前broker是slave从节点
if (BrokerRole.SLAVE == this.messageStoreConfig.getBrokerRole()) {
//根据是否配置了HA地址,来更新HA地址,并设置updateMasterHAServerAddrPeriodically
if (this.messageStoreConfig.getHaMasterAddress() != null && this.messageStoreConfig.getHaMasterAddress().length() >= 6) {
this.messageStore.updateHaMasterAddress(this.messageStoreConfig.getHaMasterAddress());
this.updateMasterHAServerAddrPeriodically = false;
} else {
this.updateMasterHAServerAddrPeriodically = true;
}
} else {
//如果是主节点,每隔60s將打印主从节点的差异
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);
}
}
//Tls传输相关配置,通信安全的文件监听模块,用来观察网络加密配置文件的更改
//默认是PERMISSIVE,因此会进入代码块
if (TlsSystemConfig.tlsMode != TlsMode.DISABLED) {
// Register a listener to reload SslContext
try {
//实例化文件监听服务,并且初始化事务消息服务。
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");
}
}
/*
* 8 初始化事务消息相关服务
*/
initialTransaction();
/*
* 9 初始化权限相关服务
*/
initialAcl();
/*
* 10 初始化RPC调用的钩子函数
*/
initialRpcHooks();
}
return result;
}
load方法加载配置文件。加载 config 路径下的json配置文件, 包括topic主题配置、offset消费偏移量、subscriptionGroup订阅分组、consumerFilter消费者过滤等配置文件。
DefaultMessageStore是RocketMQ的核心文件存储控制类, 是RocketMQ对于消息存储和获取功能的抽象。DefaultMessageStore类位于store模块, 可以直接控制管理commitLog, consumerQueue, indexFile文件的读和写。
启动Broker时候, 会创建一个DefaultMessageStore对象, load方法进行磁盘文件的加载和异常数据的修复。
public DefaultMessageStore(final MessageStoreConfig messageStoreConfig, final BrokerStatsManager
brokerStatsManager,final MessageArrivingListener messageArrivingListener, final BrokerConfig brokerConfig) throws IOException {
//消息送达的监听器,生产者消息到达时通过该监听器触发pullRequestHoldService通知pullRequestHoldService
this.messageArrivingListener = messageArrivingListener;
//Broker的配置类,包含Broker的各种配置,比如ROCKETMQ_HOME
this.brokerConfig = brokerConfig;
//Broker的消息存储配置,例如各种文件大小等
this.messageStoreConfig = messageStoreConfig;
//broker状态管理器,保存Broker运行时状态,统计工作
this.brokerStatsManager = brokerStatsManager;
//创建 MappedFile文件的服务,用于初始化MappedFile和预热MappedFile
this.allocateMappedFileService = new AllocateMappedFileService(this);
//实例化CommitLog,DLedgerCommitLog表示主持主从自动切换功能,默认是CommitLog类型
if (messageStoreConfig.isEnableDLegerCommitLog()) {
this.commitLog = new DLedgerCommitLog(this);
} else {
this.commitLog = new CommitLog(this);
}
//topic的ConsumeQueueMap的对应关系
this.consumeQueueTable = new ConcurrentHashMap<>(32);
//ConsumeQueue文件的刷盘服务
this.flushConsumeQueueService = new FlushConsumeQueueService();
//清除过期CommitLog文件的服务
this.cleanCommitLogService = new CleanCommitLogService();
//清除过期ConsumeQueue文件的服务
this.cleanConsumeQueueService = new CleanConsumeQueueService();
//存储一些统计指标信息的服务
this.storeStatsService = new StoreStatsService();
//IndexFile索引文件服务
this.indexService = new IndexService(this);
//高可用服务,默认为null
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
this.haService = new HAService(this);
} else {
this.haService = null;
}
//根据CommitLog文件,更新index文件索引和ConsumeQueue文件偏移量的服务
this.reputMessageService = new ReputMessageService();
//处理RocketMQ延迟消息的服务
this.scheduleMessageService = new ScheduleMessageService(this);
//初始化MappedFile的时候进行ByteBuffer的分配回收
this.transientStorePool = new TransientStorePool(messageStoreConfig);
//如果当前节点不是从节点,并且是异步刷盘策略,并且transientStorePoolEnable参数配置为true,则启动该服务
if (messageStoreConfig.isTransientStorePoolEnable()) {
this.transientStorePool.init();
}
//启动MappedFile文件服务线程
this.allocateMappedFileService.start();
//启动index索引文件服务线程
this.indexService.start();
//转发服务列表,监听CommitLog文件中的新消息存储,然后会调用列表中的CommitLogDispatcher#dispatch方法
this.dispatcherList = new LinkedList<>();
//通知ConsumeQueue的Dispatcher,可用于更新ConsumeQueue的偏移量等信息
this.dispatcherList.addLast(new CommitLogDispatcherBuildConsumeQueue());
//通知IndexFile的Dispatcher,可用于更新IndexFile的时间戳等信息
this.dispatcherList.addLast(new CommitLogDispatcherBuildIndex());
//获取锁文件,路径就是配置的{storePathRootDir}/lock
File file = new File(StorePathConfigHelper.getLockFile(messageStoreConfig.getStorePathRootDir()));
//确保创建file文件的父目录,即{storePathRootDir}目录
MappedFile.ensureDirOK(file.getParent());
//确保创建commitlog目录,即{StorePathCommitLog}目录
MappedFile.ensureDirOK(getStorePathPhysic());
//确保创建consumequeue目录,即{storePathRootDir}/consumequeue目录
MappedFile.ensureDirOK(getStorePathLogic());
//创建lockfile文件,名为lock,权限是"读写",这是一个锁文件,用于获取文件锁。
//文件锁用来保证磁盘上的这些存储文件同时只能有一个Broker的messageStore来操作。
lockFile = new RandomAccessFile(file, "rw");
}
lockFile: 锁文件消息。
allocateMappedFileService: 创建和预热MappedFile文件的服务。
scheduleMessageService: 消息文件刷盘或清理服务, 延迟消息处理服务。
加载实例化消息存储相关类DefaultMessageStore, 通过该类的load方法加载消息存储的相关文件, ,比如commitLog日志文件、consumequeue消息消费队列文件, indexFile索引文件, messageStore还会将这些文件的内容加载到内存中, 完成RocketMq的数据恢复。
/**
* DefaultMessageStore的方法
* 加载Commit Log、Consume Queue、index file等文件,将数据加载到内存中,并完成数据的恢复
*
* @throws IOException
*/
public boolean load() {
boolean result = true;
try {
/*
* 1 判断上次broker是否是正常退出,如果是正常退出不会保留abort文件,异常退出则会
*
* Broker在启动时会创建{storePathRootDir}/abort文件,并且注册钩子函数:在JVM退出时删除abort文件。
* 如果下一次启动时存在abort文件,说明Broker是异常退出的,文件数据可能不一直,需要进行数据修复。
*/
boolean lastExitOK = !this.isTempFileExist();
log.info("last shutdown {}", lastExitOK ? "normally" : "abnormally");
/*
* 2 加载Commit Log日志文件,目录路径取自broker.conf文件中的storePathCommitLog属性
* Commit Log文件是真正存储消息内容的地方,单个文件默认大小1G。
*/
// load Commit Log
result = result && this.commitLog.load();
/*
* 2 加载Consume Queue文件,目录路径为{storePathRootDir}/consumequeue,文件组织方式为topic/queueId/fileName
* Consume Queue文件可以看作是Commit Log的索引文件,其存储了它所属Topic的消息在Commit Log中的偏移量
* 消费者拉取消息的时候,可以从Consume Queue中快速的根据偏移量定位消息在Commit Log中的位置。
*/
// load Consume Queue
result = result && this.loadConsumeQueue();
if (result) {
/*
* 3 加载checkpoint 检查点文件,文件位置是{storePathRootDir}/checkpoint
* StoreCheckpoint记录着commitLog、ConsumeQueue、Index文件的最后更新时间点,
* 当上一次broker是异常结束时,会根据StoreCheckpoint的数据进行恢复,这决定着文件从哪里开始恢复,甚至是删除文件
*/
this.storeCheckpoint =
new StoreCheckpoint(StorePathConfigHelper.getStoreCheckpoint(this.messageStoreConfig.getStorePathRootDir()));
/*
* 4 加载 index 索引文件,目录路径为{storePathRootDir}/index
* index 索引文件用于通过时间区间来快速查询消息,底层为HashMap结构,实现为hash索引。后面会专门出文介绍
* 如果不是正常退出,并且最大更新时间戳比checkpoint文件中的时间戳大,则删除该 index 文件
*/
this.indexService.load(lastExitOK);
/*
* 4 恢复ConsumeQueue文件和CommitLog文件,将正确的的数据恢复至内存中,删除错误数据和文件。
*/
this.recover(lastExitOK);
log.info("load over, and the max phy offset = {}", this.getMaxPhyOffset());
/*
* 5 加载RocketMQ延迟消息的服务,包括延时等级、配置文件等等。
*/
if (null != scheduleMessageService) {
result = this.scheduleMessageService.load();
}
}
} catch (Exception e) {
log.error("load exception", e);
result = false;
}
if (!result) {
//如果上面的操作抛出异常,则文件服务停止
this.allocateMappedFileService.shutdown();
}
return result;
}
配置文件和日志文件加载恢复完毕后, 初始化Broker通信层和各种请求执行器。
创建两个NettyRemotingServer, 一个是普通的远程服务remotingServer, 端口号为10911, 快速的远程服务fastRemotingServer, 端口号为10909。
//创建broker的netty远程服务,端口为10911,可以用于处理客户端的所有请求。
this.remotingServer = new NettyRemotingServer(this.nettyServerConfig, this.clientHousekeepingService);
//创建一个broker的netty快速远程服务的配置
NettyServerConfig fastConfig = (NettyServerConfig) this.nettyServerConfig.clone();
//设置快速netty远程服务的配置监听的端口号为普通服务的端口-2,默认10909
fastConfig.setListenPort(nettyServerConfig.getListenPort() - 2);
//创建broker的netty快速服务,这就是所谓的快速通道,对应可以处理客户端除了拉取消息之外的所有请求,所谓的VIP端口。
this.fastRemotingServer = new NettyRemotingServer(fastConfig, this.clientHousekeepingService);
因为RocketMQ为了性能, 将许多请求进行异步处理。
/*
* 5 创建各种执行器线程池
*/
//处理发送消息的请求的线程池
this.sendMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getSendMessageThreadPoolNums(),
this.brokerConfig.getSendMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.sendThreadPoolQueue,
new ThreadFactoryImpl("SendMessageThread_"));
///https://github.com/apache/rocketmq/pull/3631
this.putMessageFutureExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getPutMessageFutureThreadPoolNums(),
this.brokerConfig.getPutMessageFutureThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.putThreadPoolQueue,
new ThreadFactoryImpl("PutMessageThread_"));
//处理拉取消息的请求的线程池
this.pullMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getPullMessageThreadPoolNums(),
this.brokerConfig.getPullMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.pullThreadPoolQueue,
new ThreadFactoryImpl("PullMessageThread_"));
//处理reply消息的请求的线程池
this.replyMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getProcessReplyMessageThreadPoolNums(),
this.brokerConfig.getProcessReplyMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.replyThreadPoolQueue,
new ThreadFactoryImpl("ProcessReplyMessageThread_"));
//处理查询请求的线程池
this.queryMessageExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getQueryMessageThreadPoolNums(),
this.brokerConfig.getQueryMessageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.queryThreadPoolQueue,
new ThreadFactoryImpl("QueryMessageThread_"));
//broker 管理线程池,作为默认处理器的线程池
this.adminBrokerExecutor =
Executors.newFixedThreadPool(this.brokerConfig.getAdminBrokerThreadPoolNums(), new ThreadFactoryImpl(
"AdminBrokerThread_"));
//客户端管理器的线程池
this.clientManageExecutor = new ThreadPoolExecutor(
this.brokerConfig.getClientManageThreadPoolNums(),
this.brokerConfig.getClientManageThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.clientManagerThreadPoolQueue,
new ThreadFactoryImpl("ClientManageThread_"));
//心跳处理的线程池
this.heartbeatExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getHeartbeatThreadPoolNums(),
this.brokerConfig.getHeartbeatThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.heartbeatThreadPoolQueue,
new ThreadFactoryImpl("HeartbeatThread_", true));
//事务消息相关处理的线程池
this.endTransactionExecutor = new BrokerFixedThreadPoolExecutor(
this.brokerConfig.getEndTransactionThreadPoolNums(),
this.brokerConfig.getEndTransactionThreadPoolNums(),
1000 * 60,
TimeUnit.MILLISECONDS,
this.endTransactionThreadPoolQueue,
new ThreadFactoryImpl("EndTransactionThread_"));
//消费者管理的线程池
this.consumerManageExecutor =
Executors.newFixedThreadPool(this.brokerConfig.getConsumerManageThreadPoolNums(), new ThreadFactoryImpl(
"ConsumerManageThread_"));
registerProcessor方法中的所有的处理器都是通过remotingServer #registerProcessor方法进行注册的。
/**
* BrokerController的方法
* 注册netty消息处理器
*/
public void registerProcessor() {
/**
* 发送消息处理器
*/
SendMessageProcessor sendProcessor = new SendMessageProcessor(this);
sendProcessor.registerSendMessageHook(sendMessageHookList);
sendProcessor.registerConsumeMessageHook(consumeMessageHookList);
//对于发送类型的请求,使用发送消息处理器sendProcessor来处理
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);
}
注册了netty消息处理器之后, 会启动一系列的定时任务, 这些任务由BrokerController中的scheduledExecutorService执行, 该线程池只有一个线程。
private final ScheduledExecutorService scheduledExecutorService =
Executors.newSingleThreadScheduledExecutor(new ThreadFactoryImpl(
"BrokerControllerScheduledThread"));
/*
* 7 启动一系列定时周期任务
*/
final long initialDelay = UtilAll.computeNextMorningTimeMillis() - System.currentTimeMillis();
//每隔24h打印昨天生产和消费的消息数量
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);
//每隔5s將消费者offset进行持久化,存入consumerOffset.json文件中
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);
//每隔10s將消费过滤信息进行持久化,存入consumerFilter.json文件中
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);
//每隔3m將检查消费者的消费进度
//当消费进度落后阈值的时候,并且disableConsumeIfConsumerReadSlowly=true(默认false),就停止消费者消费,保护broker,避免消费积压
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);
//每隔1s將打印发送消息线程池队列、拉取消息线程池队列、查询消息线程池队列、结束事务线程池队列的大小以及队列头部元素存在时间
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);
//每隔1m將打印已存储在commitlog提交日志中但尚未分派到consume queue消费队列的字节数。
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);
//如果broker的nameServer地址不为null
if (this.brokerConfig.getNamesrvAddr() != null) {
//更新nameServer地址
this.brokerOuterAPI.updateNameServerAddressList(this.brokerConfig.getNamesrvAddr());
log.info("Set user specified name server address: {}", this.brokerConfig.getNamesrvAddr());
} else if (this.brokerConfig.isFetchNamesrvAddrByAddressServer()) {
//如果没有指定nameServer地址,并且允许从地址服务器获取nameServer地址
//那么每隔2m从nameServer地址服务器拉取最新的nameServer地址并更新
//要想动态更新nameServer地址,需要指定一个地址服务器的url,并且fetchNamesrvAddrByAddressServer设置为true
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);
}
//如果没有开启DLeger服务,DLeger开启后表示支持高可用的主从自动切换
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
//如果当前broker是slave从节点
if (BrokerRole.SLAVE == this.messageStoreConfig.getBrokerRole()) {
//根据是否配置了HA地址,来更新HA地址,并设置updateMasterHAServerAddrPeriodically
if (this.messageStoreConfig.getHaMasterAddress() != null && this.messageStoreConfig.getHaMasterAddress().length() >= 6) {
this.messageStore.updateHaMasterAddress(this.messageStoreConfig.getHaMasterAddress());
this.updateMasterHAServerAddrPeriodically = false;
} else {
this.updateMasterHAServerAddrPeriodically = true;
}
} else {
//如果是主节点,每隔60s將打印主从节点的差异
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);
}
}
initialTransaction为初始化事务的方法, 事务消息的服务采用SPI的方式进行加载。
/**
* BrokerController的方法
* 初始化事务消息相关服务
*/
private void initialTransaction() {
//基于Java的SPI机制,查找"META-INF/service/org.apache.rocketmq.broker.transaction.TransactionalMessageService"文件里面的SPI实现
//事务消息服务
this.transactionalMessageService = ServiceProvider.loadClass(ServiceProvider.TRANSACTION_SERVICE_ID, TransactionalMessageService.class);
if (null == this.transactionalMessageService) {
//如果沒有通过SPI指定具体的实现,那么使用默认实现,TransactionalMessageServiceImpl
this.transactionalMessageService = new TransactionalMessageServiceImpl(new TransactionalMessageBridge(this, this.getMessageStore()));
log.warn("Load default transaction message hook service: {}", TransactionalMessageServiceImpl.class.getSimpleName());
}
//基于Java的SPI机制,查找"META-INF/service/org.apache.rocketmq.broker.transaction.AbstractTransactionalMessageCheckListener"文件里面的SPI实现
//事务消息回查服务监听器
this.transactionalMessageCheckListener = ServiceProvider.loadClass(ServiceProvider.TRANSACTION_LISTENER_ID, AbstractTransactionalMessageCheckListener.class);
if (null == this.transactionalMessageCheckListener) {
//如果沒有通过SPI指定具体的实现,那么使用默认实现,DefaultTransactionalMessageCheckListener
this.transactionalMessageCheckListener = new DefaultTransactionalMessageCheckListener();
log.warn("Load default discard message hook service: {}", DefaultTransactionalMessageCheckListener.class.getSimpleName());
}
this.transactionalMessageCheckListener.setBrokerController(this);
//创建TransactionalMessageCheckService服务,该服务内部有一个线程
//会定时每一分钟(可通过在broker.conf文件设置transactionCheckInterval属性更改)触发事务检查的逻辑,内部调用TransactionalMessageService#check方法
//默认情况下,6秒以上没commit/rollback的事务消息才会触发事务回查,而如果回查次数超过15次则丢弃事务
this.transactionalMessageCheckService = new TransactionalMessageCheckService(this);
}
加载权限相关校验器, 注册进RpcHock, 在请求执行之前执行权限校验。
/**
* BrokerController的方法
* 初始化ACL权限校验器
*/
private void initialAcl() {
//校验是否开启了ACL,默认false,所以直接返回了
if (!this.brokerConfig.isAclEnable()) {
log.info("The broker dose not enable acl");
return;
}
//如果开启了ACL,则首先通过SPI机制获取AccessValidator
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;
}
//将校验器存入accessValidatorMap,并且注册到RpcHook中,在请求之前会执行校验。
for (AccessValidator accessValidator : accessValidators) {
final AccessValidator validator = accessValidator;
accessValidatorMap.put(validator.getClass(), validator);
this.registerServerRPCHook(new RPCHook() {
@Override
public void doBeforeRequest(String remoteAddr, RemotingCommand request) {
//Do not catch the exception
//在执行请求之前会进行校验
validator.validate(validator.parse(request, remoteAddr));
}
@Override
public void doAfterResponse(String remoteAddr, RemotingCommand request, RemotingCommand response) {
}
});
}
}
基于Java的SPI机制查找RpCHook, 并注册到netty远程服务中。RpcHook是RocketMQ提供的钩子类, 可以在请求被处理之前和响应被返回之前执行对应的方法。
/**
* BrokerController的方法
* 初始化RpcHook服务
*/
private void initialRpcHooks() {
//通过SPI机制获取RPCHook的实现
List<RPCHook> rpcHooks = ServiceProvider.load(ServiceProvider.RPC_HOOK_ID, RPCHook.class);
//如果没有配置RpcHook,那么直接返回
if (rpcHooks == null || rpcHooks.isEmpty()) {
return;
}
//遍历并且注册所有的RpcHook
for (RPCHook rpcHook : rpcHooks) {
this.registerServerRPCHook(rpcHook);
}
}
// RpcHook是RocketMQ提供的钩子类
public interface RPCHook {
/**
* broker处理请求之前执行
*/
void doBeforeRequest(final String remoteAddr, final RemotingCommand request);
/**
* broker响应返回之前执行
*/
void doAfterResponse(final String remoteAddr, final RemotingCommand request,
final RemotingCommand response);
}
Broker启动时, 会监听3个端口: 10911、10911、10912
通过两个端口监听客户端请求, 达到隔离读写操作效果。消息的发送中, 重要的是提供RTT。如果普通端口堵塞, 会使得netty的IO线程阻塞, 比如消息堆积的时候, 消费消息的请求会填满IO线程池, 导致写操作被阻塞, 所以可以向vip端口发送消息。
现在发送消息和消费消息实际上默认都走10911端口。vip端口默认不开通, 需要配置属性, com.rocketmq.sendMessageWithVIPChannel属性。
创建和初始化Broker后, 启动Broker。
BrokerController#start
/**
* BrokerStartup的方法
*
* @param controller 被启动的BrokerController
*/
public static BrokerController start(BrokerController controller) {
try {
//启动broker
controller.start();
//broker启动之后的的信息打印到控制台
String tip = "The broker[" + controller.getBrokerConfig().getBrokerName() + ", "
+ controller.getBrokerAddr() + "] boot success. serializeType=" + RemotingCommand.getSerializeTypeConfigInThisServer();
if (null != controller.getBrokerConfig().getNamesrvAddr()) {
tip += " and name server is " + controller.getBrokerConfig().getNamesrvAddr();
}
log.info(tip);
System.out.printf("%s%n", tip);
return controller;
} catch (Throwable e) {
e.printStackTrace();
System.exit(-1);
}
return null;
}
启动各种服务和组件: messageStore, remotingServer, fastRemotingServer
判断如果没有开启DLedger, 如果当前broker不是SLAVE, 那么启动transactionalMessageCheckService事务消息检查服务, 如果是SLAVE, 那么启动定时任务每隔10s与master机器同步数据, 采用slave主动拉取的方法。
最后还会开启另一个定时周期任务, 默认情况下每隔30s向所有的nameServer进行一次注册broker信息, 时间间隔可以配置registerNameServerPeriod属性, 允许的值是在1万到6万毫秒之间。这个任务是Broker向nameServer发送心跳包的定时任务, 包含topic读、写队列个数、队列权限、是否有序等信息。
/**
* BrokerController的方法
* 启动BrokerController
*/
public void start() throws Exception {
//启动消息存储服务
if (this.messageStore != null) {
this.messageStore.start();
}
//启动netty远程服务
if (this.remotingServer != null) {
this.remotingServer.start();
}
//启动快速netty远程服务
if (this.fastRemotingServer != null) {
this.fastRemotingServer.start();
}
//文件监听器启动
if (this.fileWatchService != null) {
this.fileWatchService.start();
}
//broker对外api启动
if (this.brokerOuterAPI != null) {
this.brokerOuterAPI.start();
}
//长轮询拉取消息挂起服务启动
if (this.pullRequestHoldService != null) {
this.pullRequestHoldService.start();
}
//客户端连接心跳服务启动
if (this.clientHousekeepingService != null) {
this.clientHousekeepingService.start();
}
//过滤服务管理器启动
if (this.filterServerManager != null) {
this.filterServerManager.start();
}
//如果没有开启DLeger的相关设置,默认没有启动
if (!messageStoreConfig.isEnableDLegerCommitLog()) {
//如果不是SLAVE,那么启动transactionalMessageCheckService事务消息检查服务
startProcessorByHa(messageStoreConfig.getBrokerRole());
//如果是SLAVE,那么启动定时任务每隔10s与master机器同步数据,采用slave主动拉取的方法
//同步的内容包括topic配置,消费者消费位移、延迟消息偏移量、订阅组信息等
handleSlaveSynchronize(messageStoreConfig.getBrokerRole());
/*
* 强制注册当前broker信息到所有的nameserver
*/
this.registerBrokerAll(true, false, true);
}
//启动定时任务,默认情况下每隔30s向nameServer进行一次注册,
//时间间隔可以配置registerNameServerPeriod属性,允许的值是在1万到6万毫秒之间。
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
try {
//定时发送心跳包并上报数据
BrokerController.this.registerBrokerAll(true, false, brokerConfig.isForceRegister());
} catch (Throwable e) {
log.error("registerBrokerAll Exception", e);
}
}
}, 1000 * 10, Math.max(10000, Math.min(brokerConfig.getRegisterNameServerPeriod(), 60000)), TimeUnit.MILLISECONDS);
//broker相关统计服务启动
if (this.brokerStatsManager != null) {
this.brokerStatsManager.start();
}
//broker快速失败服务启动
if (this.brokerFastFailure != null) {
this.brokerFastFailure.start();
}
}
实例化和初始化BrokerController, 启动BrokerController。
Broker模块启动时还会加载很多的文件, 比如topic.json, 消费者的信息, consumerOffset.json。
加载各种消息文件, commitLog, consumerQueue, indexFile, 加载后会恢复文件。