broker接收消息
1 broker收到消息
broker启动netty server 端，用来处理客户端的消息，
@Override
public void start() {
this.defaultEventExecutorGroup = new DefaultEventExecutorGroup(
nettyServerConfig.getServerWorkerThreads(),
new ThreadFactory() {
private AtomicInteger threadIndex = new AtomicInteger(0);
@Override
public Thread newThread(Runnable r) {
return new Thread(r, "NettyServerCodecThread_" + this.threadIndex.incrementAndGet());
}
});
/**
* 整个启动过程与RemotingClient类似, 使用的handler也类似, 区别在于RemotingServerz.
* 服务器端以后添加的handler是NettyServerHandler(客户端用的是NettyClientHandler).
* 服务器端接收到请求后, 对消息的处理逻辑在NettyRemotingAbstract中(此处省略了一大波
* netty框架接收到消息后的数据流转过程),
*/
ServerBootstrap childHandler =
this.serverBootstrap.group(this.eventLoopGroupBoss, this.eventLoopGroupSelector).channel(NioServerSocketChannel.class)
.option(ChannelOption.SO_BACKLOG, 1024)
.option(ChannelOption.SO_REUSEADDR, true)
.option(ChannelOption.SO_KEEPALIVE, false)
.childOption(ChannelOption.TCP_NODELAY, true)
.option(ChannelOption.SO_SNDBUF, nettyServerConfig.getServerSocketSndBufSize())
.option(ChannelOption.SO_RCVBUF, nettyServerConfig.getServerSocketRcvBufSize())
.localAddress(new InetSocketAddress(this.nettyServerConfig.getListenPort()))
.childHandler(new ChannelInitializer<SocketChannel>() {
@Override
public void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast(
defaultEventExecutorGroup,
new NettyEncoder(),
new NettyDecoder(),
new IdleStateHandler(0, 0, nettyServerConfig.getServerChannelMaxIdleTimeSeconds()),
new NettyConnetManageHandler(),
new NettyServerHandler());
}
});
if (nettyServerConfig.isServerPooledByteBufAllocatorEnable()) {
childHandler.childOption(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT);
}
try {
ChannelFuture sync = this.serverBootstrap.bind().sync();
InetSocketAddress addr = (InetSocketAddress) sync.channel().localAddress();
this.port = addr.getPort();
} catch (InterruptedException e1) {
throw new RuntimeException("this.serverBootstrap.bind().sync() InterruptedException", e1);
}
//如果 channelEventListener 不为 null， 则启动一个专门的线程监听 Channel 的各种事件。
if (this.channelEventListener != null) {
this.nettyEventExecuter.start();
}
//随后，则启动一个定时器，每隔一段时间查看 responseTable 是否有超时未回应的请求，并完成一些清理工作
this.timer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
try {
NettyRemotingServer.this.scanResponseTable();
} catch (Exception e) {
log.error("scanResponseTable exception", e);
}
}
}, 1000 * 3, 1000);
}
class NettyServerHandler extends SimpleChannelInboundHandler<RemotingCommand> {
@Override
protected void channelRead0(ChannelHandlerContext ctx, RemotingCommand msg) throws Exception {
processMessageReceived(ctx, msg);
}
}
/**
* 在这里，请求可以分为两类，一类是处理别的服务发来的请求；另外一类是处理自己发给别的服务的请求的处理结果。所有的请求其实都是异步的，
* 只是将请求相关的 ResponseFuture记在一个 ConcurrentHashMap 中，map 的 key 为与请求相关的一个整数
* @param ctx
* @param msg
* @throws Exception
*/
public void processMessageReceived(ChannelHandlerContext ctx, RemotingCommand msg) throws Exception {
final RemotingCommand cmd = msg;
if (cmd != null) {
switch (cmd.getType()) {
case REQUEST_COMMAND:
processRequestCommand(ctx, cmd);
break;
case RESPONSE_COMMAND:
processResponseCommand(ctx, cmd);
break;
default:
break;
}
}
}
private RemotingCommand sendMessage(final ChannelHandlerContext ctx, //
final RemotingCommand request, //
final SendMessageContext sendMessageContext, //
final SendMessageRequestHeader requestHeader) throws RemotingCommandException {
// 初始化响应
final RemotingCommand response = RemotingCommand.createResponseCommand(SendMessageResponseHeader.class);
final SendMessageResponseHeader responseHeader = (SendMessageResponseHeader) response.readCustomHeader();
response.setOpaque(request.getOpaque());
response.addExtField(MessageConst.PROPERTY_MSG_REGION, this.brokerController.getBrokerConfig().getRegionId());
response.addExtField(MessageConst.PROPERTY_TRACE_SWITCH, String.valueOf(this.brokerController.getBrokerConfig().isTraceOn()));
if (log.isDebugEnabled()) {
log.debug("receive SendMessage request command, {}", request);
}
// 如果未开始接收消息，抛出系统异常
final long startTimstamp = this.brokerController.getBrokerConfig().getStartAcceptSendRequestTimeStamp();
if (this.brokerController.getMessageStore().now() < startTimstamp) {
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark(String.format("broker unable to service, until %s", UtilAll.timeMillisToHumanString2(startTimstamp)));
return response;
}
// 消息配置(Topic配置）校验
response.setCode(-1);
super.msgCheck(ctx, requestHeader, response);
if (response.getCode() != -1) {
return response;
}
....
}
2 检查消息topic
上篇说到，如果话题信息在 Name 服务器不存在的话，那么会使用默认话题信息进行消息的发送。然而一旦这条消息到来之后，Broker 端还并没有这个话题。所以 Broker 需要检查话题的存在性:
protected RemotingCommand msgCheck(final ChannelHandlerContext ctx,
final SendMessageRequestHeader requestHeader, final RemotingCommand response) {
// 检查 broker 是否有写入权限
if (!PermName.isWriteable(this.brokerController.getBrokerConfig().getBrokerPermission())
&& this.brokerController.getTopicConfigManager().isOrderTopic(requestHeader.getTopic())) {
response.setCode(ResponseCode.NO_PERMISSION);
response.setRemark("the broker[" + this.brokerController.getBrokerConfig().getBrokerIP1()
+ "] sending message is forbidden");
return response;
}
// 检查topic是否可以被发送。目前是{@link MixAll.DEFAULT_TOPIC}不被允许发送
if (!this.brokerController.getTopicConfigManager().isTopicCanSendMessage(requestHeader.getTopic())) {
String errorMsg = "the topic[" + requestHeader.getTopic() + "] is conflict with system reserved words.";
log.warn(errorMsg);
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark(errorMsg);
return response;
}
TopicConfig topicConfig =
this.brokerController.getTopicConfigManager().selectTopicConfig(requestHeader.getTopic());
if (null == topicConfig) {
int topicSysFlag = 0;
if (requestHeader.isUnitMode()) {
if (requestHeader.getTopic().startsWith(MixAll.RETRY_GROUP_TOPIC_PREFIX)) {
topicSysFlag = TopicSysFlag.buildSysFlag(false, true);
} else {
topicSysFlag = TopicSysFlag.buildSysFlag(true, false);
}
}
log.warn("the topic {} not exist, producer: {}", requestHeader.getTopic(), ctx.channel().remoteAddress());
//如果话题不存在的话，那么便会创建一个话题信息存储到本地，并将所有话题再进行一次同步给所有的 Name 服务器
topicConfig = this.brokerController.getTopicConfigManager().createTopicInSendMessageMethod(//
requestHeader.getTopic(), //
requestHeader.getDefaultTopic(), //
RemotingHelper.parseChannelRemoteAddr(ctx.channel()), //
requestHeader.getDefaultTopicQueueNums(), topicSysFlag);
if (null == topicConfig) {
if (requestHeader.getTopic().startsWith(MixAll.RETRY_GROUP_TOPIC_PREFIX)) {
topicConfig =
this.brokerController.getTopicConfigManager().createTopicInSendMessageBackMethod(
requestHeader.getTopic(), 1, PermName.PERM_WRITE | PermName.PERM_READ,
topicSysFlag);
}
}
if (null == topicConfig) {
response.setCode(ResponseCode.TOPIC_NOT_EXIST);
response.setRemark("topic[" + requestHeader.getTopic() + "] not exist, apply first please!"
+ FAQUrl.suggestTodo(FAQUrl.APPLY_TOPIC_URL));
return response;
}
}
int queueIdInt = requestHeader.getQueueId();
int idValid = Math.max(topicConfig.getWriteQueueNums(), topicConfig.getReadQueueNums());
if (queueIdInt >= idValid) {
String errorInfo = String.format("request queueId[%d] is illagal, %s Producer: %s",
queueIdInt,
topicConfig.toString(),
RemotingHelper.parseChannelRemoteAddr(ctx.channel()));
log.warn(errorInfo);
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark(errorInfo);
return response;
}
return response;
}
话题检查的整体流程如下所示:
public TopicConfig createTopicInSendMessageMethod(final String topic, final String defaultTopic,
final String remoteAddress, final int clientDefaultTopicQueueNums, final int topicSysFlag) {
TopicConfig topicConfig = null;
boolean createNew = false;
try {
if (this.lockTopicConfigTable.tryLock(LOCK_TIMEOUT_MILLIS, TimeUnit.MILLISECONDS)) {
try {
topicConfig = this.topicConfigTable.get(topic);
if (topicConfig != null)
return topicConfig;
TopicConfig defaultTopicConfig = this.topicConfigTable.get(defaultTopic);
if (defaultTopicConfig != null) {
if (defaultTopic.equals(MixAll.DEFAULT_TOPIC)) {
if (!this.brokerController.getBrokerConfig().isAutoCreateTopicEnable()) {
defaultTopicConfig.setPerm(PermName.PERM_READ | PermName.PERM_WRITE);
}
}
if (PermName.isInherited(defaultTopicConfig.getPerm())) {
topicConfig = new TopicConfig(topic);
int queueNums =
clientDefaultTopicQueueNums > defaultTopicConfig.getWriteQueueNums() ? defaultTopicConfig
.getWriteQueueNums() : clientDefaultTopicQueueNums;
if (queueNums < 0) {
queueNums = 0;
}
topicConfig.setReadQueueNums(queueNums);
topicConfig.setWriteQueueNums(queueNums);
int perm = defaultTopicConfig.getPerm();
perm &= ~PermName.PERM_INHERIT;
topicConfig.setPerm(perm);
topicConfig.setTopicSysFlag(topicSysFlag);
topicConfig.setTopicFilterType(defaultTopicConfig.getTopicFilterType());
} else {
LOG.warn("Create new topic failed, because the default topic[{}] has no perm [{}] producer:[{}]",
defaultTopic, defaultTopicConfig.getPerm(), remoteAddress);
}
} else {
LOG.warn("Create new topic failed, because the default topic[{}] not exist. producer:[{}]", defaultTopic, remoteAddress);
}
if (topicConfig != null) {
LOG.info("Create new topic by default topic:[{}] config:[{}] producer:[{}]", defaultTopic, topicConfig, remoteAddress);
this.topicConfigTable.put(topic, topicConfig);
this.dataVersion.nextVersion();
createNew = true;
this.persist();
}
} finally {
this.lockTopicConfigTable.unlock();
}
}
} catch (InterruptedException e) {
LOG.error("createTopicInSendMessageMethod exception", e);
}
if (createNew) {
this.brokerController.registerBrokerAll(false, true);
}
return topicConfig;
}
3 消息存储
当 Broker 对消息的一些字段做过一番必要的检查之后，便会存储到磁盘中去:
MessageExtBrokerInner msgInner = new MessageExtBrokerInner();
msgInner.setTopic(newTopic);
msgInner.setBody(body);
msgInner.setFlag(requestHeader.getFlag());
MessageAccessor.setProperties(msgInner, MessageDecoder.string2messageProperties(requestHeader.getProperties()));
msgInner.setPropertiesString(requestHeader.getProperties());
msgInner.setTagsCode(MessageExtBrokerInner.tagsString2tagsCode(topicConfig.getTopicFilterType(), msgInner.getTags()));
msgInner.setQueueId(queueIdInt);
msgInner.setSysFlag(sysFlag);
msgInner.setBornTimestamp(requestHeader.getBornTimestamp());
msgInner.setBornHost(ctx.channel().remoteAddress());
msgInner.setStoreHost(this.getStoreHost());
msgInner.setReconsumeTimes(requestHeader.getReconsumeTimes() == null ? 0 : requestHeader.getReconsumeTimes());
if (this.brokerController.getBrokerConfig().isRejectTransactionMessage()) {
String traFlag = msgInner.getProperty(MessageConst.PROPERTY_TRANSACTION_PREPARED);
if (traFlag != null) {
response.setCode(ResponseCode.NO_PERMISSION);
response.setRemark(
"the broker[" + this.brokerController.getBrokerConfig().getBrokerIP1() + "] sending transaction message is forbidden");
return response;
}
}
PutMessageResult putMessageResult = this.brokerController.getMessageStore().putMessage(msgInner);
if (putMessageResult != null) {
boolean sendOK = false;
switch (putMessageResult.getPutMessageStatus()) {
// Success
case PUT_OK:
sendOK = true;
response.setCode(ResponseCode.SUCCESS);
break;
case FLUSH_DISK_TIMEOUT:
response.setCode(ResponseCode.FLUSH_DISK_TIMEOUT);
sendOK = true;
break;
case FLUSH_SLAVE_TIMEOUT:
response.setCode(ResponseCode.FLUSH_SLAVE_TIMEOUT);
sendOK = true;
break;
case SLAVE_NOT_AVAILABLE:
response.setCode(ResponseCode.SLAVE_NOT_AVAILABLE);
sendOK = true;
break;
// Failed
case CREATE_MAPEDFILE_FAILED:
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark("create mapped file failed, server is busy or broken.");
break;
case MESSAGE_ILLEGAL:
case PROPERTIES_SIZE_EXCEEDED:
response.setCode(ResponseCode.MESSAGE_ILLEGAL);
response.setRemark(
"the message is illegal, maybe msg body or properties length not matched. msg body length limit 128k, msg properties length limit 32k.");
break;
case SERVICE_NOT_AVAILABLE:
response.setCode(ResponseCode.SERVICE_NOT_AVAILABLE);
response.setRemark(
"service not available now, maybe disk full, " + diskUtil() + ", maybe your broker machine memory too small.");
break;
case OS_PAGECACHE_BUSY:
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark("[PC_SYNCHRONIZED]broker busy, start flow control for a while");
break;
case UNKNOWN_ERROR:
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark("UNKNOWN_ERROR");
break;
default:
response.setCode(ResponseCode.SYSTEM_ERROR);
response.setRemark("UNKNOWN_ERROR DEFAULT");
break;
}
@Override
public PutMessageResult putMessage(MessageExtBrokerInner msg) {
if (this.shutdown) {
log.warn("message store has shutdown, so putMessage is forbidden");
return new PutMessageResult(PutMessageStatus.SERVICE_NOT_AVAILABLE, null);
}
// 从节点不允许写入
if (BrokerRole.SLAVE == this.messageStoreConfig.getBrokerRole()) {
long value = this.printTimes.getAndIncrement();
if ((value % 50000) == 0) {
log.warn("message store is slave mode, so putMessage is forbidden ");
}
return new PutMessageResult(PutMessageStatus.SERVICE_NOT_AVAILABLE, null);
}
// store是否允许写入
if (!this.runningFlags.isWriteable()) {
long value = this.printTimes.getAndIncrement();
if ((value % 50000) == 0) {
log.warn("message store is not writeable, so putMessage is forbidden " + this.runningFlags.getFlagBits());
}
return new PutMessageResult(PutMessageStatus.SERVICE_NOT_AVAILABLE, null);
} else {
this.printTimes.set(0);
}
// 消息过长
if (msg.getTopic().length() > Byte.MAX_VALUE) {
log.warn("putMessage message topic length too long " + msg.getTopic().length());
return new PutMessageResult(PutMessageStatus.MESSAGE_ILLEGAL, null);
}
// 消息附加属性过长
if (msg.getPropertiesString() != null && msg.getPropertiesString().length() > Short.MAX_VALUE) {
log.warn("putMessage message properties length too long " + msg.getPropertiesString().length());
return new PutMessageResult(PutMessageStatus.PROPERTIES_SIZE_EXCEEDED, null);
}
if (this.isOSPageCacheBusy()) {
return new PutMessageResult(PutMessageStatus.OS_PAGECACHE_BUSY, null);
}
// 添加消息到commitLog
long beginTime = this.getSystemClock().now();
PutMessageResult result = this.commitLog.putMessage(msg);
long eclipseTime = this.getSystemClock().now() - beginTime;
if (eclipseTime > 500) {
log.warn("putMessage not in lock eclipse time(ms)={}, bodyLength={}", eclipseTime, msg.getBody().length);
}
this.storeStatsService.setPutMessageEntireTimeMax(eclipseTime);
if (null == result || !result.isOk()) {
this.storeStatsService.getPutMessageFailedTimes().incrementAndGet();
}
return result;
}