消息中间件rocketmq（下）
1、nameserver
nameserver用来维护配置信息、状态信息、producer和consumer的加入和退出，是消息队列中的状态服务器。
之所以不用zk，是因为只需要轻量级的元数据管理中心。
NamesrvStartup启动->新建NamesrvController->initialize方法
public boolean initialize() {
//从持久化文件中加载配置到内存
this.kvConfigManager.load();
this.remotingServer = new NettyRemotingServer(this.nettyServerConfig, this.brokerHousekeepingService);
//初始化netty执行器 8个线程
this.remotingExecutor =
Executors.newFixedThreadPool(nettyServerConfig.getServerWorkerThreads(), new ThreadFactoryImpl("RemotingExecutorThread_"));
//注册处理器
this.registerProcessor();
/**
* initialDelay 延迟首次执行的时间 5s
* period 连续执行的时间间隔 10s
* 定时扫描死掉的Broker
*/
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
NamesrvController.this.routeInfoManager.scanNotActiveBroker();
}
}, 5, 10, TimeUnit.SECONDS);
//定期打印kvConfigManager的配置
this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
NamesrvController.this.kvConfigManager.printAllPeriodically();
}
}, 1, 10, TimeUnit.MINUTES);
if (TlsSystemConfig.tlsMode != TlsMode.DISABLED) {
// Register a listener to reload SslContext 注册一个监听器重新加载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();
}
});
} catch (Exception e) {
log.warn("FileWatchService created error, can't load the certificate dynamically");
}
}
return true;
}
RoutelnfoManager：该类中的五个变量保存着集群信息
public class RouteInfoManager {
private static final InternalLogger log = InternalLoggerFactory.getLogger(LoggerName.NAMESRV_LOGGER_NAME);
private final static long BROKER_CHANNEL_EXPIRED_TIME = 1000 * 60 * 2;
// 读写锁
private final ReadWriteLock lock = new ReentrantReadWriteLock();
// Topic,以及对应的队列信息
private final HashMap<String/* topic */, List<QueueData>> topicQueueTable;
// 以Broker Name为单位的Broker集合
private final HashMap<String/* brokerName */, BrokerData> brokerAddrTable;
// 集群以及属于该集群的Broker列表
private final HashMap<String/* clusterName */, Set<String/* brokerName */>> clusterAddrTable;
// 存活的Broker地址列表
private final HashMap<String/* brokerAddr */, BrokerLiveInfo> brokerLiveTable;
// Broker对应的Filter Server列表
private final HashMap<String/* brokerAddr */, List<String>/* Filter Server */> filterServerTable;
public RouteInfoManager() {
this.topicQueueTable = new HashMap<String, List<QueueData>>(1024);
this.brokerAddrTable = new HashMap<String, BrokerData>(128);
this.clusterAddrTable = new HashMap<String, Set<String>>(32);
this.brokerLiveTable = new HashMap<String, BrokerLiveInfo>(256);
this.filterServerTable = new HashMap<String, List<String>>(256);
}
}
DefaultRequestProcessor：用于响应客户端、Broker的请求。
消息处理类型：获取元数据信息，注册、解注册broker、获取关于topic的路由
public class DefaultRequestProcessor extends AsyncNettyRequestProcessor implements NettyRequestProcessor {
private static InternalLogger log = InternalLoggerFactory.getLogger(LoggerName.NAMESRV_LOGGER_NAME);
protected final NamesrvController namesrvController;
public DefaultRequestProcessor(NamesrvController namesrvController) {
this.namesrvController = namesrvController;
}
@Override
public RemotingCommand processRequest(ChannelHandlerContext ctx,
RemotingCommand request) throws RemotingCommandException {
if (ctx != null) {
log.debug("receive request, {} {} {}",
request.getCode(),
RemotingHelper.parseChannelRemoteAddr(ctx.channel()),
request);
}
switch (request.getCode()) {
case RequestCode.PUT_KV_CONFIG:
return this.putKVConfig(ctx, request);
case RequestCode.GET_KV_CONFIG:
return this.getKVConfig(ctx, request);
case RequestCode.DELETE_KV_CONFIG:
return this.deleteKVConfig(ctx, request);
case RequestCode.QUERY_DATA_VERSION:
return queryBrokerTopicConfig(ctx, request);
case RequestCode.REGISTER_BROKER:
Version brokerVersion = MQVersion.value2Version(request.getVersion());
if (brokerVersion.ordinal() >= MQVersion.Version.V3_0_11.ordinal()) {
return this.registerBrokerWithFilterServer(ctx, request);
} else {
return this.registerBroker(ctx, request);
}
case RequestCode.UNREGISTER_BROKER:
return this.unregisterBroker(ctx, request);
case RequestCode.GET_ROUTEINFO_BY_TOPIC:
return this.getRouteInfoByTopic(ctx, request);
case RequestCode.GET_BROKER_CLUSTER_INFO:
return this.getBrokerClusterInfo(ctx, request);
case RequestCode.WIPE_WRITE_PERM_OF_BROKER:
return this.wipeWritePermOfBroker(ctx, request);
case RequestCode.ADD_WRITE_PERM_OF_BROKER:
return this.addWritePermOfBroker(ctx, request);
case RequestCode.GET_ALL_TOPIC_LIST_FROM_NAMESERVER:
return getAllTopicListFromNameserver(ctx, request);
case RequestCode.DELETE_TOPIC_IN_NAMESRV:
return deleteTopicInNamesrv(ctx, request);
case RequestCode.GET_KVLIST_BY_NAMESPACE:
return this.getKVListByNamespace(ctx, request);
case RequestCode.GET_TOPICS_BY_CLUSTER:
return this.getTopicsByCluster(ctx, request);
case RequestCode.GET_SYSTEM_TOPIC_LIST_FROM_NS:
return this.getSystemTopicListFromNs(ctx, request);
case RequestCode.GET_UNIT_TOPIC_LIST:
return this.getUnitTopicList(ctx, request);
case RequestCode.GET_HAS_UNIT_SUB_TOPIC_LIST:
return this.getHasUnitSubTopicList(ctx, request);
case RequestCode.GET_HAS_UNIT_SUB_UNUNIT_TOPIC_LIST:
return this.getHasUnitSubUnUnitTopicList(ctx, request);
case RequestCode.UPDATE_NAMESRV_CONFIG:
return this.updateConfig(ctx, request);
case RequestCode.GET_NAMESRV_CONFIG:
return this.getConfig(ctx, request);
default:
break;
}
return null;
}
}
BrokerHousekeepingService：处理Broker连接发生变化的服务。
public class BrokerHousekeepingService implements ChannelEventListener {
private static final InternalLogger log = InternalLoggerFactory.getLogger(LoggerName.NAMESRV_LOGGER_NAME);
private final NamesrvController namesrvController;
public BrokerHousekeepingService(NamesrvController namesrvController) {
this.namesrvController = namesrvController;
}
@Override
public void onChannelConnect(String remoteAddr, Channel channel) {
}
@Override
public void onChannelClose(String remoteAddr, Channel channel) {
this.namesrvController.getRouteInfoManager().onChannelDestroy(remoteAddr, channel);
}
@Override
public void onChannelException(String remoteAddr, Channel channel) {
this.namesrvController.getRouteInfoManager().onChannelDestroy(remoteAddr, channel);
}
@Override
public void onChannelIdle(String remoteAddr, Channel channel) {
this.namesrvController.getRouteInfoManager().onChannelDestroy(remoteAddr, channel);
}
}
2、底层通信机制