activemq-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jesse Fugitt (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (AMQ-5347) persistJMSRedelivered flag doesn't work correctly when exceptions occur
Date Fri, 31 Oct 2014 19:33:34 GMT

    [ https://issues.apache.org/jira/browse/AMQ-5347?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14192307#comment-14192307
] 

Jesse Fugitt commented on AMQ-5347:
-----------------------------------

Great thanks.  Killing the connection was the important thing and the runtime exception looks
like it accomplishes that.  Originally, I looked at a way to sneak the exception through the
interface since changing would impact so many files/plugins but ended up just submitting the
patch so that the intent was clear.  Glad you were able to get this in.

> persistJMSRedelivered flag doesn't work correctly when exceptions occur
> -----------------------------------------------------------------------
>
>                 Key: AMQ-5347
>                 URL: https://issues.apache.org/jira/browse/AMQ-5347
>             Project: ActiveMQ
>          Issue Type: Bug
>          Components: Broker
>    Affects Versions: 5.10.0
>            Reporter: Jesse Fugitt
>            Assignee: Gary Tully
>             Fix For: 5.11.0
>
>         Attachments: AMQ5347.patch, RedeliveryRestartWithExceptionTest.java
>
>
> The new flag in 5.10 that ensures the JMSRedelivered flag persists across broker restarts
does not work correctly when an exception occurs when attempting to write the "message update"
to disk before the restart.  In that case, messages can be assigned to receivers, the broker
can be restarted, and then the messages are re-assigned to receivers and do not include the
JMSRedelivered flag as expected.  I will attach a unit test and proposed fix to illustrate
the problem.
> Also, here is additional information I had sent to the mailing list:
> When using the new option persisteJMSRedelivered (to ensure the redelivered flag is set
correctly on potentially duplicate messages that are re-dispatched by the broker even after
a restart): <policyEntry queue=">" persistJMSRedelivered="true"></policyEntry>
> there is still a case where a message can be re-sent and will not be marked as redelivered.
 I can open a JIRA and probably create a unit test but it is pretty clear from the pasted
code below where the exception is getting swallowed.  Would the preferred fix be to update
the broker interface and make preProcessDispatch throw an IOException or would it be better
to add a new field to the MessageDispatch class to indicate an exception occurred and leave
the interface alone?
> The specific case when this can happen is when a MessageStore returns an exception during
the updateMessage call, which then gets swallowed (and an ERROR logged) and still allows the
message to be dispatched to the consumer.  The exception seems like it should actually propagate
out of the preProcessDispatch function in RegionBroker as shown below, but this would require
changing the Broker interface and making the void preProcessDispatch function throw an IOException.
> //RegionBroker.java
>     @Override
>     public void preProcessDispatch(MessageDispatch messageDispatch) {
>         Message message = messageDispatch.getMessage();
>         if (message != null) {
>             long endTime = System.currentTimeMillis();
>             message.setBrokerOutTime(endTime);
>             if (getBrokerService().isEnableStatistics()) {
>                 long totalTime = endTime - message.getBrokerInTime();
>                 ((Destination) message.getRegionDestination()).getDestinationStatistics().getProcessTime().addTime(totalTime);
>             }
>             if (((BaseDestination) message.getRegionDestination()).isPersistJMSRedelivered()
&& !message.isRedelivered() && message.isPersistent()) {
>                 final int originalValue = message.getRedeliveryCounter();
>                 message.incrementRedeliveryCounter();
>                 try {
>                     ((BaseDestination) message.getRegionDestination()).getMessageStore().updateMessage(message);
>                 } catch (IOException error) {
>                     LOG.error("Failed to persist JMSRedeliveryFlag on {} in {}", message.getMessageId(),
message.getDestination(), error);
>                 } finally {
>                     message.setRedeliveryCounter(originalValue);
>                 }
>             }
>         }
>     }
> //TransportConnection.java
>     protected void processDispatch(Command command) throws IOException {
>         MessageDispatch messageDispatch = (MessageDispatch) (command.isMessageDispatch()
? command : null);
>         try {
>             if (!stopping.get()) {
>                 if (messageDispatch != null) {
>                     broker.preProcessDispatch(messageDispatch);
>                 }
>                 dispatch(command);  //This code will dispatch the message whether or
not the updateMessage function actually worked
>             }
>         ...



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message