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本文主要研究一下rocketmq的ConsumeMode.CONCURRENTLY
ConsumeMode.CONCURRENTLY
rocketmq-spring-boot-2.0.4-sources.jar!/org/apache/rocketmq/spring/annotation/ConsumeMode.java
public enum ConsumeMode {
/**
* Receive asynchronously delivered messages concurrently
*/
CONCURRENTLY,
/**
* Receive asynchronously delivered messages orderly. one queue, one thread
*/
ORDERLY
}
- ConsumeMode定义了CONCURRENTLY、ORDERLY两个枚举值
DefaultRocketMQListenerContainer
rocketmq-spring-boot-2.0.4-sources.jar!/org/apache/rocketmq/spring/support/DefaultRocketMQListenerContainer.java
public class DefaultRocketMQListenerContainer implements InitializingBean,
RocketMQListenerContainer, SmartLifecycle, ApplicationContextAware {
//......
private void initRocketMQPushConsumer() throws MQClientException {
Assert.notNull(rocketMQListener, "Property 'rocketMQListener' is required");
Assert.notNull(consumerGroup, "Property 'consumerGroup' is required");
Assert.notNull(nameServer, "Property 'nameServer' is required");
Assert.notNull(topic, "Property 'topic' is required");
RPCHook rpcHook = RocketMQUtil.getRPCHookByAkSk(applicationContext.getEnvironment(),
this.rocketMQMessageListener.accessKey(), this.rocketMQMessageListener.secretKey());
boolean enableMsgTrace = rocketMQMessageListener.enableMsgTrace();
if (Objects.nonNull(rpcHook)) {
consumer = new DefaultMQPushConsumer(consumerGroup, rpcHook, new AllocateMessageQueueAveragely(),
enableMsgTrace, this.applicationContext.getEnvironment().
resolveRequiredPlaceholders(this.rocketMQMessageListener.customizedTraceTopic()));
consumer.setVipChannelEnabled(false);
consumer.setInstanceName(RocketMQUtil.getInstanceName(rpcHook, consumerGroup));
} else {
log.debug("Access-key or secret-key not configure in " + this + ".");
consumer = new DefaultMQPushConsumer(consumerGroup, enableMsgTrace,
this.applicationContext.getEnvironment().
resolveRequiredPlaceholders(this.rocketMQMessageListener.customizedTraceTopic()));
}
String customizedNameServer = this.applicationContext.getEnvironment().resolveRequiredPlaceholders(this.rocketMQMessageListener.nameServer());
if (customizedNameServer != null) {
consumer.setNamesrvAddr(customizedNameServer);
} else {
consumer.setNamesrvAddr(nameServer);
}
if (accessChannel != null) {
consumer.setAccessChannel(accessChannel);
}
consumer.setConsumeThreadMax(consumeThreadMax);
if (consumeThreadMax < consumer.getConsumeThreadMin()) {
consumer.setConsumeThreadMin(consumeThreadMax);
}
consumer.setConsumeTimeout(consumeTimeout);
switch (messageModel) {
case BROADCASTING:
consumer.setMessageModel(org.apache.rocketmq.common.protocol.heartbeat.MessageModel.BROADCASTING);
break;
case CLUSTERING:
consumer.setMessageModel(org.apache.rocketmq.common.protocol.heartbeat.MessageModel.CLUSTERING);
break;
default:
throw new IllegalArgumentException("Property 'messageModel' was wrong.");
}
switch (selectorType) {
case TAG:
consumer.subscribe(topic, selectorExpression);
break;
case SQL92:
consumer.subscribe(topic, MessageSelector.bySql(selectorExpression));
break;
default:
throw new IllegalArgumentException("Property 'selectorType' was wrong.");
}
switch (consumeMode) {
case ORDERLY:
consumer.setMessageListener(new DefaultMessageListenerOrderly());
break;
case CONCURRENTLY:
consumer.setMessageListener(new DefaultMessageListenerConcurrently());
break;
default:
throw new IllegalArgumentException("Property 'consumeMode' was wrong.");
}
if (rocketMQListener instanceof RocketMQPushConsumerLifecycleListener) {
((RocketMQPushConsumerLifecycleListener) rocketMQListener).prepareStart(consumer);
}
}
}
- initRocketMQPushConsumer方法对于consumeMode为CONCURRENTLY则设置的messageListener为DefaultMessageListenerConcurrently
DefaultMessageListenerConcurrently
rocketmq-spring-boot-2.0.4-sources.jar!/org/apache/rocketmq/spring/support/DefaultRocketMQListenerContainer.java
public class DefaultMessageListenerConcurrently implements MessageListenerConcurrently {
@SuppressWarnings("unchecked")
@Override
public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
for (MessageExt messageExt : msgs) {
log.debug("received msg: {}", messageExt);
try {
long now = System.currentTimeMillis();
rocketMQListener.onMessage(doConvertMessage(messageExt));
long costTime = System.currentTimeMillis() - now;
log.debug("consume {} cost: {} ms", messageExt.getMsgId(), costTime);
} catch (Exception e) {
log.warn("consume message failed. messageExt:{}", messageExt, e);
context.setDelayLevelWhenNextConsume(delayLevelWhenNextConsume);
return ConsumeConcurrentlyStatus.RECONSUME_LATER;
}
}
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
}
}
- DefaultMessageListenerConcurrently实现了MessageListenerConcurrently接口，其consumeMessage方法遍历msgs，然后挨个调用rocketMQListener.onMessage(doConvertMessage(messageExt))，若循环中出现异常被捕获住了会执行context.setDelayLevelWhenNextConsume(delayLevelWhenNextConsume)，然后返回ConsumeConcurrentlyStatus.RECONSUME_LATER
ConsumeMessageConcurrentlyService
rocketmq-client-4.6.0-sources.jar!/org/apache/rocketmq/client/impl/consumer/ConsumeMessageConcurrentlyService.java
class ConsumeRequest implements Runnable {
private final List<MessageExt> msgs;
private final ProcessQueue processQueue;
private final MessageQueue messageQueue;
public ConsumeRequest(List<MessageExt> msgs, ProcessQueue processQueue, MessageQueue messageQueue) {
this.msgs = msgs;
this.processQueue = processQueue;
this.messageQueue = messageQueue;
}
public List<MessageExt> getMsgs() {
return msgs;
}
public ProcessQueue getProcessQueue() {
return processQueue;
}
@Override
public void run() {
if (this.processQueue.isDropped()) {
log.info("the message queue not be able to consume, because it's dropped. group={} {}", ConsumeMessageConcurrentlyService.this.consumerGroup, this.messageQueue);
return;
}
MessageListenerConcurrently listener = ConsumeMessageConcurrentlyService.this.messageListener;
ConsumeConcurrentlyContext context = new ConsumeConcurrentlyContext(messageQueue);
ConsumeConcurrentlyStatus status = null;
defaultMQPushConsumerImpl.resetRetryAndNamespace(msgs, defaultMQPushConsumer.getConsumerGroup());
ConsumeMessageContext consumeMessageContext = null;
if (ConsumeMessageConcurrentlyService.this.defaultMQPushConsumerImpl.hasHook()) {
consumeMessageContext = new ConsumeMessageContext();
consumeMessageContext.setNamespace(defaultMQPushConsumer.getNamespace());
consumeMessageContext.setConsumerGroup(defaultMQPushConsumer.getConsumerGroup());
consumeMessageContext.setProps(new HashMap<String, String>());
consumeMessageContext.setMq(messageQueue);
consumeMessageContext.setMsgList(msgs);
consumeMessageContext.setSuccess(false);
ConsumeMessageConcurrentlyService.this.defaultMQPushConsumerImpl.executeHookBefore(consumeMessageContext);
}
long beginTimestamp = System.currentTimeMillis();
boolean hasException = false;
ConsumeReturnType returnType = ConsumeReturnType.SUCCESS;
try {
if (msgs != null && !msgs.isEmpty()) {
for (MessageExt msg : msgs) {
MessageAccessor.setConsumeStartTimeStamp(msg, String.valueOf(System.currentTimeMillis()));
}
}
status = listener.consumeMessage(Collections.unmodifiableList(msgs), context);
} catch (Throwable e) {
log.warn("consumeMessage exception: {} Group: {} Msgs: {} MQ: {}",
RemotingHelper.exceptionSimpleDesc(e),
ConsumeMessageConcurrentlyService.this.consumerGroup,
msgs,
messageQueue);
hasException = true;
}
long consumeRT = System.currentTimeMillis() - beginTimestamp;
if (null == status) {
if (hasException) {
returnType = ConsumeReturnType.EXCEPTION;
} else {
returnType = ConsumeReturnType.RETURNNULL;
}
} else if (consumeRT >= defaultMQPushConsumer.getConsumeTimeout() * 60 * 1000) {
returnType = ConsumeReturnType.TIME_OUT;
} else if (ConsumeConcurrentlyStatus.RECONSUME_LATER == status) {
returnType = ConsumeReturnType.FAILED;
} else if (ConsumeConcurrentlyStatus.CONSUME_SUCCESS == status) {
returnType = ConsumeReturnType.SUCCESS;
}
if (ConsumeMessageConcurrentlyService.this.defaultMQPushConsumerImpl.hasHook()) {
consumeMessageContext.getProps().put(MixAll.CONSUME_CONTEXT_TYPE, returnType.name());
}
if (null == status) {
log.warn("consumeMessage return null, Group: {} Msgs: {} MQ: {}",
ConsumeMessageConcurrentlyService.this.consumerGroup,
msgs,
messageQueue);
status = ConsumeConcurrentlyStatus.RECONSUME_LATER;
}
if (ConsumeMessageConcurrentlyService.this.defaultMQPushConsumerImpl.hasHook()) {
consumeMessageContext.setStatus(status.toString());
consumeMessageContext.setSuccess(ConsumeConcurrentlyStatus.CONSUME_SUCCESS == status);
ConsumeMessageConcurrentlyService.this.defaultMQPushConsumerImpl.executeHookAfter(consumeMessageContext);
}
ConsumeMessageConcurrentlyService.this.getConsumerStatsManager()
.incConsumeRT(ConsumeMessageConcurrentlyService.this.consumerGroup, messageQueue.getTopic(), consumeRT);
if (!processQueue.isDropped()) {
ConsumeMessageConcurrentlyService.this.processConsumeResult(status, context, this);
} else {
log.warn("processQueue is dropped without process consume result. messageQueue={}, msgs={}", messageQueue, msgs);
}
}
public MessageQueue getMessageQueue() {
return messageQueue;
}
}
- ConsumeRequest实现了Runnable接口，它的构造器要求传入msgs、processQueue、messageQueue参数；其run方法会执行listener.consumeMessage(Collections.unmodifiableList(msgs), context)以及processConsumeResult(status, context, this)
小结
DefaultMessageListenerConcurrently实现了MessageListenerConcurrently接口，其consumeMessage方法遍历msgs，然后挨个调用rocketMQListener.onMessage(doConvertMessage(messageExt))，若循环中出现异常被捕获住了会执行context.setDelayLevelWhenNextConsume(delayLevelWhenNextConsume)，然后返回ConsumeConcurrentlyStatus.RECONSUME_LATER
ConsumeMessageConcurrentlyService.ConsumeRequest不需要自己去拉取msgs，而ConsumeMessageOrderlyService.ConsumeRequest需要自己先加锁，然后拉取msgs
