RocketMQ-Namesrv

前言

在看完rocketmq通信层的源码之后,再来看namesrv的代码相对容易些,rocketmq的服务注册和发现并没有采用zookeeper这样的开源分布式协作框架,而是自研了一套服务注册和发现的服务,相对来说比较简单,多个namesrv之间不相互通信,也不是主从关系。

namesrv主要有两个作用,一个是路由信息注册和通知,另外一个是K-V存储。

namesrv启动

if [ -z "$ROCKETMQ_HOME" ] ; then
  ## resolve links - $0 may be a link to maven's home
  PRG="$0"

  # need this for relative symlinks
  while [ -h "$PRG" ] ; do
    ls=`ls -ld "$PRG"`
    link=`expr "$ls" : '.*-> (.*)$'`
    if expr "$link" : '/.*' > /dev/null; then
      PRG="$link"
    else
      PRG="`dirname "$PRG"`/$link"
    fi
  done

  saveddir=`pwd`

  ROCKETMQ_HOME=`dirname "$PRG"`/..

  # make it fully qualified
  ROCKETMQ_HOME=`cd "$ROCKETMQ_HOME" && pwd`

  cd "$saveddir"
fi

export ROCKETMQ_HOME

sh ${ROCKETMQ_HOME}/bin/runserver.sh org.apache.rocketmq.namesrv.NamesrvStartup $@

执行ruunserver.sh  获取java环境相关信息和JVM配置  最后启动 org.apache.rocketmq.namesrv.NamesrvStartup 的main方法

error_exit ()
{
    echo "ERROR: $1 !!"
    exit 1
}

[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=$HOME/jdk/java
[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=/usr/java
[ ! -e "$JAVA_HOME/bin/java" ] && error_exit "Please set the JAVA_HOME variable in your environment, We need java(x64)!"

export JAVA_HOME
export JAVA="$JAVA_HOME/bin/java"
export BASE_DIR=$(dirname $0)/..
export CLASSPATH=.:${BASE_DIR}/conf:${CLASSPATH}

#===========================================================================================
# JVM Configuration
#===========================================================================================
JAVA_OPT="${JAVA_OPT} -server -Xms4g -Xmx4g -Xmn2g -XX:PermSize=128m -XX:MaxPermSize=320m"
JAVA_OPT="${JAVA_OPT} -XX:+UseConcMarkSweepGC -XX:+UseCMSCompactAtFullCollection -XX:CMSInitiatingOccupancyFraction=70 -XX:+CMSParallelRemarkEnabled -XX:SoftRefLRUPolicyMSPerMB=0 -XX:+CMSClassUnloadingEnabled -XX:SurvivorRatio=8 -XX:+DisableExplicitGC -XX:-UseParNewGC"
JAVA_OPT="${JAVA_OPT} -verbose:gc -Xloggc:/dev/shm/rmq_srv_gc.log -XX:+PrintGCDetails"
JAVA_OPT="${JAVA_OPT} -XX:-OmitStackTraceInFastThrow"
JAVA_OPT="${JAVA_OPT}  -XX:-UseLargePages"
JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${BASE_DIR}/lib"
#JAVA_OPT="${JAVA_OPT} -Xdebug -Xrunjdwp:transport=dt_socket,address=9555,server=y,suspend=n"
JAVA_OPT="${JAVA_OPT} ${JAVA_OPT_EXT}"
JAVA_OPT="${JAVA_OPT} -cp ${CLASSPATH}"

$JAVA ${JAVA_OPT} $@

NamesrvStartup 使用apache的CommandLine来获取命令行中的参数初始化namesrv的配置。

其中 -c 表示namesrvConfig和nettyServerConfig的存储读写路径   -p表示是否打印配置 ,并初始化日志,调用controller的init和start

// remember all configs to prevent discard
            controller.getConfiguration().registerConfig(properties);

            boolean initResult = controller.initialize();
            if (!initResult) {
                controller.shutdown();
                System.exit(-3);
            }
       // 设置JVM关闭钩子
            Runtime.getRuntime().addShutdownHook(new ShutdownHookThread(log, new Callable<Void>() {
                @Override
                public Void call() throws Exception {
                    controller.shutdown();
                    return null;
                }
            }));

            controller.start();

            String tip = "The Name Server boot success. serializeType=" + RemotingCommand.getSerializeTypeConfigInThisServer();
            log.info(tip);
            System.out.printf(tip + "%n");

namesrv初始化

 public NamesrvController(NamesrvConfig namesrvConfig, NettyServerConfig nettyServerConfig) {
        this.namesrvConfig = namesrvConfig;
        this.nettyServerConfig = nettyServerConfig;
        this.kvConfigManager = new KVConfigManager(this);
        this.routeInfoManager = new RouteInfoManager();
        // 网络事件监听  当有broker断开,会自动更新本地路由表
        this.brokerHousekeepingService = new BrokerHousekeepingService(this);
        this.configuration = new Configuration(
                log,
                this.namesrvConfig, this.nettyServerConfig
        );
        // 存放namesrvConfig  
        this.configuration.setStorePathFromConfig(this.namesrvConfig, "configStorePath");
    }
public boolean initialize() {

        // 加载Kvconfig.jso到内存
        this.kvConfigManager.load();

        // 初始化remotingServer
        this.remotingServer = new NettyRemotingServer(this.nettyServerConfig, this.brokerHousekeepingService);

        // 处理业务线程池
        this.remotingExecutor =
                Executors.newFixedThreadPool(nettyServerConfig.getServerWorkerThreads(), new ThreadFactoryImpl("RemotingExecutorThread_"));

        // 注册处理器
        this.registerProcessor();

        // 检测无效的broker
        this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {

            @Override
            public void run() {
                NamesrvController.this.routeInfoManager.scanNotActiveBroker();
            }
        }, 5, 10, TimeUnit.SECONDS);

        // 打印 k-v配置
        this.scheduledExecutorService.scheduleAtFixedRate(new Runnable() {

            @Override
            public void run() {
                NamesrvController.this.kvConfigManager.printAllPeriodically();
            }
        }, 1, 10, TimeUnit.MINUTES);

        return true;
    }

然后调用strart方法启动

this.remotingServer.start();

namesrv实现

主要功能

switch (request.getCode()) {
            case RequestCode.PUT_KV_CONFIG:  // 存KV
                return this.putKVConfig(ctx, request);
            case RequestCode.GET_KV_CONFIG:  //取KV
                return this.getKVConfig(ctx, request);
            case RequestCode.DELETE_KV_CONFIG: // 删除KV
                return this.deleteKVConfig(ctx, request);
            case RequestCode.REGISTER_BROKER: // 注册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:  // 注销broker
                return this.unregisterBroker(ctx, request);
            case RequestCode.GET_ROUTEINTO_BY_TOPIC: // 根据topic获取路由表
                return this.getRouteInfoByTopic(ctx, request);
            case RequestCode.GET_BROKER_CLUSTER_INFO:  //获取集群中broker信息
                return this.getBrokerClusterInfo(ctx, request);
            case RequestCode.WIPE_WRITE_PERM_OF_BROKER: // 删除broker的写权限
                return this.wipeWritePermOfBroker(ctx, request);
            case RequestCode.GET_ALL_TOPIC_LIST_FROM_NAMESERVER: // 获取所有的topic信息
                return getAllTopicListFromNameserver(ctx, request);
            case RequestCode.DELETE_TOPIC_IN_NAMESRV:  // 删除某个topic信息
                return deleteTopicInNamesrv(ctx, request);
            case RequestCode.GET_KVLIST_BY_NAMESPACE:  // 获取namespace下的所有KV
                return this.getKVListByNamespace(ctx, request);
            case RequestCode.GET_TOPICS_BY_CLUSTER:  // 获取集群中的topic
                return this.getTopicsByCluster(ctx, request);
            case RequestCode.GET_SYSTEM_TOPIC_LIST_FROM_NS:  // 获取系统topic
                return this.getSystemTopicListFromNs(ctx, request);
            case RequestCode.GET_UNIT_TOPIC_LIST:  // 获取 unit topic
                return this.getUnitTopicList(ctx, request);
            case RequestCode.GET_HAS_UNIT_SUB_TOPIC_LIST: // 获取 unit SUB topic  ,比如 %RETRY% TOPIC
                return this.getHasUnitSubTopicList(ctx, request);
            case RequestCode.GET_HAS_UNIT_SUB_UNUNIT_TOPIC_LIST: //
                return this.getHasUnitSubUnUnitTopicList(ctx, request);
            case RequestCode.UPDATE_NAMESRV_CONFIG: // 更新namesrv的配置
                return this.updateConfig(ctx, request);
            case RequestCode.GET_NAMESRV_CONFIG:  // 获取namesrv的配置
                return this.getConfig(ctx, request);
            default:
                break;
        }
        return null;

路由表数据结构

// 一个topic 与多个broker的对应关系
    private final HashMap<String/* topic */, List<QueueData>> topicQueueTable;
    // 一个brokerName 与 brokername信息的对应关系   包含主从broker地址信息    一对主从节点使用同一个brokername
    private final HashMap<String/* brokerName */, BrokerData> brokerAddrTable;
    // 定义了一个集群包含哪些brokerName
    private final HashMap<String/* clusterName */, Set<String/* brokerName */>> clusterAddrTable;
    // 一个broker的主机地址  存储了网络channel  版本 以及HA的服务地址
    private final HashMap<String/* brokerAddr */, BrokerLiveInfo> brokerLiveTable;
    //  定义了一个broker主机对应的过滤服务器组
    private final HashMap<String/* brokerAddr */, List<String>/* Filter Server */> filterServerTable;

接下来看一下几个关键操作

注册broker

    public RemotingCommand registerBrokerWithFilterServer(ChannelHandlerContext ctx, RemotingCommand request)
        throws RemotingCommandException {
        // 定义响应对象
        final RemotingCommand response = RemotingCommand.createResponseCommand(RegisterBrokerResponseHeader.class);
        final RegisterBrokerResponseHeader responseHeader = (RegisterBrokerResponseHeader) response.readCustomHeader();
        final RegisterBrokerRequestHeader requestHeader =
            (RegisterBrokerRequestHeader) request.decodeCommandCustomHeader(RegisterBrokerRequestHeader.class);

        RegisterBrokerBody registerBrokerBody = new RegisterBrokerBody();

        if (request.getBody() != null) {
            registerBrokerBody = RegisterBrokerBody.decode(request.getBody(), RegisterBrokerBody.class);
        } else {
            // 没有body的时候 给registerBrokerBody的DataVersion和Timestamp 初始化
            registerBrokerBody.getTopicConfigSerializeWrapper().getDataVersion().setCounter(new AtomicLong(0));
            registerBrokerBody.getTopicConfigSerializeWrapper().getDataVersion().setTimestamp(0);
        }

        // 主要是注册内存中
        RegisterBrokerResult result = this.namesrvController.getRouteInfoManager().registerBroker(
            requestHeader.getClusterName(),
            requestHeader.getBrokerAddr(),
            requestHeader.getBrokerName(),
            requestHeader.getBrokerId(),
            requestHeader.getHaServerAddr(),
            registerBrokerBody.getTopicConfigSerializeWrapper(),
            registerBrokerBody.getFilterServerList(),
            ctx.channel());

        responseHeader.setHaServerAddr(result.getHaServerAddr());
        responseHeader.setMasterAddr(result.getMasterAddr());

        // 返回KV配置
        byte[] jsonValue = this.namesrvController.getKvConfigManager().getKVListByNamespace(NamesrvUtil.NAMESPACE_ORDER_TOPIC_CONFIG);
        response.setBody(jsonValue);

        response.setCode(ResponseCode.SUCCESS);
        response.setRemark(null);
        return response;
    }

当broker挂了  在事件监听器中可以监听到网络的变化,并更新内存

public class BrokerHousekeepingService implements ChannelEventListener {
    private static final Logger log = LoggerFactory.getLogger(LoggerName.NAMESRV_LOGGER_NAME);
    private final NamesrvController namesrvController;

    public BrokerHousekeepingService(NamesrvController namesrvController) {
        this.namesrvController = namesrvController;
    }

    @Override
    public void onChannelConnect(String remoteAddr, Channel channel) {
        // 如果为了实现实时通知到product或者sonsumer  可以在这边缓存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);
    }
}

获取路由信息

public TopicRouteData pickupTopicRouteData(final String topic) {
        TopicRouteData topicRouteData = new TopicRouteData();
        boolean foundQueueData = false;
        boolean foundBrokerData = false;
        Set<String> brokerNameSet = new HashSet<String>();
        List<BrokerData> brokerDataList = new LinkedList<BrokerData>();
        topicRouteData.setBrokerDatas(brokerDataList);

        HashMap<String, List<String>> filterServerMap = new HashMap<String, List<String>>();
        topicRouteData.setFilterServerTable(filterServerMap);

        try {
            try {
                this.lock.readLock().lockInterruptibly();
                // 根据topic获取一组brokername
                List<QueueData> queueDataList = this.topicQueueTable.get(topic);
                if (queueDataList != null) {
                    topicRouteData.setQueueDatas(queueDataList);
                    foundQueueData = true;

                    Iterator<QueueData> it = queueDataList.iterator();
                    while (it.hasNext()) {
                        QueueData qd = it.next();
                        brokerNameSet.add(qd.getBrokerName());
                    }

                    for (String brokerName : brokerNameSet) {
                        BrokerData brokerData = this.brokerAddrTable.get(brokerName);
                        if (null != brokerData) {
                            BrokerData brokerDataClone = new BrokerData(brokerData.getCluster(), brokerData.getBrokerName(), (HashMap<Long, String>) brokerData
                                .getBrokerAddrs().clone());
                            brokerDataList.add(brokerDataClone);
                            foundBrokerData = true;
                            // 每一个brokerName都有对个broker主机  包含主从节点,每一个broker节点,都对应一组过滤服务器节点
                            for (final String brokerAddr : brokerDataClone.getBrokerAddrs().values()) {
                                List<String> filterServerList = this.filterServerTable.get(brokerAddr);
                                filterServerMap.put(brokerAddr, filterServerList);
                            }
                        }
                    }
                }
            } finally {
                this.lock.readLock().unlock();
            }
        } catch (Exception e) {
            log.error("pickupTopicRouteData Exception", e);
        }

        if (log.isDebugEnabled()) {
            log.debug("pickupTopicRouteData {} {}", topic, topicRouteData);
        }

        if (foundBrokerData && foundQueueData) {
            return topicRouteData;
        }

        return null;


原文地址:https://www.cnblogs.com/gaojy/p/15077740.html