You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@rocketmq.apache.org by "vongosling (JIRA)" <ji...@apache.org> on 2017/12/13 11:58:00 UTC
[jira] [Closed] (ROCKETMQ-180) CONSUME_FROM_TIMESTAMP will repeat
the last message though timestamp is new enough
[ https://issues.apache.org/jira/browse/ROCKETMQ-180?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
vongosling closed ROCKETMQ-180.
-------------------------------
Resolution: Later
Fix Version/s: (was: 4.2.0)
> CONSUME_FROM_TIMESTAMP will repeat the last message though timestamp is new enough
> ----------------------------------------------------------------------------------
>
> Key: ROCKETMQ-180
> URL: https://issues.apache.org/jira/browse/ROCKETMQ-180
> Project: Apache RocketMQ
> Issue Type: Bug
> Components: rocketmq-client
> Affects Versions: 4.0.0-incubating
> Reporter: Jaskey Lam
> Assignee: Xiaorui Wang
>
> When using CONSUME_FROM_TIMESTAMP , rocketmq will try to search latest offset and use it for first pull
> However, the search offset function will always return a existing offset, which will cause repeated message though the last message is old enough and has been consumed already.
> This problem has been found in BROADCASTING mode, but the same problem should exist in CLUSTERING mode.
> Problem code snippet
> {code}
> case CONSUME_FROM_TIMESTAMP: {
> long lastOffset = offsetStore.readOffset(mq, ReadOffsetType.READ_FROM_STORE);
> if (lastOffset >= 0) {
> result = lastOffset;
> } else if (-1 == lastOffset) {
> if (mq.getTopic().startsWith(MixAll.RETRY_GROUP_TOPIC_PREFIX)) {
> try {
> result = this.mQClientFactory.getMQAdminImpl().maxOffset(mq);
> } catch (MQClientException e) {
> result = -1;
> }
> } else {
> try {
> long timestamp = UtilAll.parseDate(this.defaultMQPushConsumerImpl.getDefaultMQPushConsumer().getConsumeTimestamp(),
> UtilAll.YYYY_MMDD_HHMMSS).getTime();
> result = this.mQClientFactory.getMQAdminImpl().searchOffset(mq, timestamp);// Here!! This represents a message that has been stored.
> } catch (MQClientException e) {
> result = -1;
> }
> }
> } else {
> result = -1;
> }
> break;
> }
> {code}
> A reason to cause producing this bug when writing code is that the word "offset" does not repesent it's real meaning in RocketMQ, which has been demonstrated in https://issues.apache.org/jira/browse/ROCKETMQ-105?filter=-2 , this should also be noticed and paid attention to, to avoid more similar mistakes.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)