camel-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jeff Bischoff <jbisch...@wdtablesystems.com>
Subject Re: Why do I get so many "external redeliveries" when using Camel with JMS topics?
Date Tue, 17 Jun 2014 15:59:51 GMT
Not using a queue, just an AMQ topic. Was working fine before I introduced
Camel, so I think I must be misconfiguring something in Camel.

If I do <rollback/> everything works, but if I do <stop/>, then my
non-Camel subscriber never gets the message. It's almost as if my Camel
consumer is not actually creating a subscription on the topic, but is
instead stealing the message intended for my non-camel subscriber.

Does it make sense that rollback would even work on this route? It isn't
marked <transacted/> and the AMQConnector has no transaction manager
defined! Yet rollback seems to work.

        <route id="configuration.topic-out">
                        <from uri="table-jms:topic:configuration.topic"/>
                        <log message="Picked up message with id: ${id},
destinationType: ${header.DestinationEntityType}" loggingLevel="INFO"/>
loggingLevel="INFO"/>
                        <choice>
                                <when>

<simple>${header.DestinationEntityType} not in 'FOO,BAR'</simple>
                                        <log message="Detected new
${header.Name} configuration.topic message on ${header.JMSDestination} for
destination ${header.DestinationEntityType} with id: ${id}"
loggingLevel="INFO"/>
                                        <to
uri="lc-jms:topic:configuration.topic?requestTimeout=0"/>
                                        <log message="Successfully
processed message with id: ${id}, destinationType:
${header.DestinationEntityType}" loggingLevel="INFO"/>
                                </when>
                                <otherwise>
                                        <log message="(otherwise) ignoring
message with id: ${id}, destinationType: ${header.DestinationEntityType}"
loggingLevel="INFO"/>
                                        <rollback markRollbackOnly="true"
/>
                                </otherwise>
                        </choice>
                </route>


Results in:

[topic-out] (Camel (camelContext) thread #9 -
JmsConsumer[configuration.topic]) Picked up message with id:
ID:TS-0007-jbischoff-2.local-50312-1403019963746-1:2:3:1:1,
destinationType: TABLE

[topic-out] (Camel (camelContext) thread #9 -
JmsConsumer[configuration.topic]) (otherwise) ignoring message with id:
ID:TS-0007-jbischoff-2.local-50312-1403019963746-1:2:3:1:1,
destinationType: TABLE

[EndpointMessageListener] (Camel (camelContext) thread #9 -
JmsConsumer[configuration.topic]) Execution of JMS message listener
failed. Caused by: [org.apache.camel.RuntimeCamelException -
org.apache.camel.RollbackExchangeException: Intended rollback.
Exchange[JmsMessage[JmsMessageID:
ID:TS-0007-jbischoff-2.local-50312-1403019963746-1:2:3:1:1]]]



Best,

Jeff



On 6/17/14 10:59 AM, "kraythe ." <kraythe@gmail.com> wrote:

>A JMS topic will send a copy of each message to every topic. If not then
>the system violates basic JMS spec. If the system is a mainstream system
>like ActiveMQ, then that is not your problem. If you are trying to use a
>queue as a topic it doesn't work that way.
>
>A queue is like throwing candy into the middle of a class of elementary
>kids. Each piece of candy will get consumed by only one kid but they will
>scramble for the pieces of candy as fast as they can. However, if a kid
>eats a piece of candy they can't regurgitate it and put it back into the
>pile.
>
>In your case if a route consumes a message on the queue, then it can't put
>it back on the queue, the only way it gets back there is if the route
>fails
>and rolls back.
>
>Try adding a log line or a DLQ to the otherwise and see what happens. And
>don't rollback in the otherwise. If you are using a queue, create a route
>to sort the queue into 2 other queues based on the criteria and then
>another route to process the queue where the relevant messages end up.
>i.e.
>from(my
>queue).choice().when(predicate).to("jms:queue:camel-processed-queue).other
>wise().to("jms:queue:queue-processed-externally")
>
>
>*Robert Simmons Jr. MSc. - Lead Java Architect @ EA*
>*Author of: Maintainable Java (Kindle
><http://www.amazon.com/Maintainable-Java-Robert-Simmons-Jr-ebook/dp/B00AKH
>I69K>)(iTunes
><https://itunes.apple.com/us/book/maintainable-java/id585666097?mt=11>)*
>*LinkedIn: **http://www.linkedin.com/pub/robert-simmons/40/852/a39
><http://www.linkedin.com/pub/robert-simmons/40/852/a39>*
>
>
>On Tue, Jun 17, 2014 at 9:27 AM, Jeff Bischoff
><jbischoff@wdtablesystems.com
>> wrote:
>
>> Robert, thanks so much for replying.
>>
>> > Without that ack, the external system thinks it is not consumed and in
>> >good faith tries to redeliver.
>>
>> Okay, that seems like a good explanation for why I am getting external
>> redeliveries!
>>
>> I guess the root of my problem is that it seems like my Camel consumer
>>is
>> competing with my non-Camel topic subscribers. To your question:
>>
>> > So the question you have to decide to solve your problem is, "What is
>>the
>> > route I want my messages to take if they are not in the when
>>condition.
>> >Do
>> > they end up in a dead letter queue? Routed elsewhere? Logged to a
>>file?
>> >But
>> > they have to end up somewhere.
>>
>> I have non-Camel endpoints that will pick up the messages that don't
>>meet
>> the filter requirements. Ideally, I would have an "otherwise" that does
>> nothing with the message (but does send the ack that it has been
>> processed). These particular messages do not need to be routed by Camel
>>in
>> my system.
>>
>> However, it seems like Camel is competing with my non-Camel endpoints to
>> consumer topic messages. I would have thought each subscriber (Camel and
>> the other subscriber) would get their own copy of the topic message, and
>> that they would not compete with each other. It seems like the non-Camel
>> consumer can only process the message if I do a "rollback" in Camel.
>>
>> I'm building JUnit tests to try to figure out what I'm doing wrong, but
>> any further insight would be greatly appreciated.
>>
>>
>> Best,
>>
>> Jeff
>>
>>
>>
>> On 6/17/14 9:16 AM, "kraythe ." <kraythe@gmail.com> wrote:
>>
>> >Good suggestions but you will need to check the JMS server config if
>>you
>> >are getting external redeliveries. Those happen when an external
>>system to
>> >the camel route performs a redelivery.
>> >
>> >As for your original route, there must always be a place for an
>>exchange
>> >to
>> >go or it will stop routing. In the case of your when without otherwise,
>> >what would be the path of the exchange that fails the when condition?
>>It
>> >is
>> >probably returned to the external system in some manner and not acked
>>as
>> >being delivered so it is sent again. Without that ack, the external
>>system
>> >thinks it is not consumed and in good faith tries to redeliver.
>> >
>> >Furthermore when you rollback, you are telling the host JMS system that
>> >you
>> >did not consume the message, and it will try again of course.
>> >
>> >So the question you have to decide to solve your problem is, "What is
>>the
>> >route I want my messages to take if they are not in the when
>>condition. Do
>> >they end up in a dead letter queue? Routed elsewhere? Logged to a file?
>> >But
>> >they have to end up somewhere.
>> >
>> >*Robert Simmons Jr. MSc. - Lead Java Architect @ EA*
>> >*Author of: Hardcore Java (2003) and Maintainable Java (2012)*
>> >*LinkedIn: **http://www.linkedin.com/pub/robert-simmons/40/852/a39
>> ><http://www.linkedin.com/pub/robert-simmons/40/852/a39>*
>> >
>> >
>> >On Mon, Jun 16, 2014 at 5:56 PM, Minh Tran <darth.minhster@gmail.com>
>> >wrote:
>> >
>> >> I have used topics in camel and they generally work the way I expect
>>it.
>> >>
>> >> I would start by leaving the cache levels at the default and
>>simplifying
>> >> your route further. eg take out the choice and send it direct from
>> >>topic to
>> >> queue. Then add the choice but send it directly to the queue without
>>the
>> >> recipient list. Also enable tracing on the camel context so you can
>>see
>> >> what is happening to your message each step of the way.
>> >>
>> >> On 17/06/2014, at 6:28 AM, Jeff Bischoff
>><jbischoff@wdtablesystems.com>
>> >> wrote:
>> >>
>> >> > Does nobody use Topics with Camel? They don't seem to work as
>> >>expected.
>> >> >
>> >> > JB
>> >> >
>> >> > On 5/30/14 10:48 AM, "Jeff Bischoff" <jbischoff@wdtablesystems.com>
>> >> wrote:
>> >> >
>> >> >> Correction:
>> >> >>
>> >> >> 1) Why would *CACHE_CONSUMER* on the ActiveMQComponent cause
>>endless
>> >> >> external
>> >> >> redeliveries of a (filtered out) topic message, when with other
>>cache
>> >> >> settings (like CACHE_SESSION) this does not occur?
>> >> >>
>> >> >>
>> >> >>
>> >> >>
>> >> >> On 5/30/14 10:39 AM, "Jeff Bischoff"
>><jbischoff@wdtablesystems.com>
>> >> wrote:
>> >> >>
>> >> >>> Maybe I need to narrow my questions:
>> >> >>>
>> >> >>> 1) Why would CACHE_SESSION on the ActiveMQComponent cause endless
>> >> >>> external
>> >> >>> redeliveries of a (filtered out) topic message, when with other
>> >>cache
>> >> >>> settings this does not occur?
>> >> >>>
>> >> >>> 2) Why would <rollback/> prevent the external redeliveries,
but
>> >><stop/>
>> >> >>> does not prevent them?
>> >> >>>
>> >> >>>
>> >> >>> Did I provide enough info below to answer these questions?
Topics
>> >>just
>> >> >>> aren't working in Camel the way that I would expect!
>> >> >>>
>> >> >>> Thanks,
>> >> >>>
>> >> >>> Jeff Bischoff
>> >> >>> WDTS
>> >> >>>
>> >> >>> On 5/29/14 4:25 PM, "Jeff Bischoff"
>><jbischoff@wdtablesystems.com>
>> >> wrote:
>> >> >>>
>> >> >>>> Hi all,
>> >> >>>>
>> >> >>>> Please forgive me if this is a basic question.
>> >> >>>>
>> >> >>>> Working with Camel and JMS Topics has seemed very finicky
for
>>me so
>> >> far.
>> >> >>>> If I make slight configuration changes, I see the same
message
>> >> repeated
>> >> >>>> endlessly. Using jconsole, I now know these messages are
>>"external
>> >> >>>> redeliveries", i.e. the same message is being sent from
JMS to
>> >>Camel
>> >> >>>> repeatedly without ever getting through. It happens in
the case
>>of
>> >> >>>> messages that I am intentionally not processing due to
some
>> >>criteria.
>> >> >>>> What I don't understand is why these external redeliveries
keep
>> >> >>>> occurring, when I simply want this message to be dropped.
>> >> >>>>
>> >> >>>> For example, if I use CACHE_SESSION or lower cache level,
the
>> >> following
>> >> >>>> route works just fine for me:
>> >> >>>>
>> >> >>>>
>> >> >>>>       <route id="topics-out">
>> >> >>>>           <from uri="topic-jms:topic:projectx.>"/>
>> >> >>>>           <log message="Picked up message with id: ${id},
>> >> >>>> destinationType: ${header.DestinationEntityType}"
>> >> loggingLevel="INFO"/>
>> >> >>>>           <choice>
>> >> >>>>               <when>
>> >> >>>>                   <simple>${header.DestinationEntityType}
not in
>> >> >>>> 'FOO,BAR'</simple>
>> >> >>>>                   <log message="Detected new ${header.Name}
>>topic
>> >> >>>> message on ${header.JMSDestination} with id: ${id},
>> >>destinationType:
>> >> >>>> ${header.DestinationEntityType}" loggingLevel="INFO"/>
>> >> >>>>                   <recipientList ignoreInvalidEndpoints="false">
>> >> >>>>
>> >><simple>lc-jms:${header.JMSDestination}</simple>
>> >> >>>>                   </recipientList>
>> >> >>>>               </when>
>> >> >>>>           </choice>
>> >> >>>>       </route>
>> >> >>>>
>> >> >>>>
>> >> >>>> However, if I switch to CACHE_CONSUMER and I have even
one
>>message
>> >> >>>> addressed to 'FOO' or 'BAR', I will see the endless external
>> >> >>>> redeliveries. Note that I am using a SingleConnectionFactory
>> >> >>>> specifically
>> >> >>>> for this route.
>> >> >>>>
>> >> >>>>       <route id="topics-out">
>> >> >>>>           <from uri="topic-jms:topic:projectx.>"/>
>> >> >>>>           <log message="Picked up message with id: ${id},
>> >> >>>> destinationType: ${header.DestinationEntityType}"
>> >> loggingLevel="INFO"/>
>> >> >>>>           <choice>
>> >> >>>>               <when>
>> >> >>>>                   <simple>${header.DestinationEntityType}
not in
>> >> >>>> 'FOO,BAR'</simple>
>> >> >>>>                   <log message="Detected new ${header.Name}
>>topic
>> >> >>>> message on ${header.JMSDestination} with id: ${id},
>> >>destinationType:
>> >> >>>> ${header.DestinationEntityType}" loggingLevel="INFO"/>
>> >> >>>>                   <recipientList ignoreInvalidEndpoints="false">
>> >> >>>>
>> >><simple>lc-jms:${header.JMSDestination}</simple>
>> >> >>>>                   </recipientList>
>> >> >>>>               </when>
>> >> >>>>           </choice>
>> >> >>>>       </route>
>> >> >>>>
>> >> >>>> Now, if I add an Otherwise clause with a Rollback, everything
>>works
>> >> fine
>> >> >>>> again (albeit with a handful of log messages due to the
>>rollbacks):
>> >> >>>>
>> >> >>>>       <route id="topics-out">
>> >> >>>>           <from uri="topic-jms:topic:projectx.>"/>
>> >> >>>>           <log message="Picked up message with id: ${id},
>> >> >>>> destinationType: ${header.DestinationEntityType}"
>> >> loggingLevel="INFO"/>
>> >> >>>>           <choice>
>> >> >>>>               <when>
>> >> >>>>                   <simple>${header.DestinationEntityType}
not in
>> >> >>>> 'FOO,BAR'</simple>
>> >> >>>>                   <log message="Detected new ${header.Name}
>>topic
>> >> >>>> message on ${header.JMSDestination} with id: ${id},
>> >>destinationType:
>> >> >>>> ${header.DestinationEntityType}" loggingLevel="INFO"/>
>> >> >>>>                   <recipientList ignoreInvalidEndpoints="false">
>> >> >>>>
>> >><simple>lc-jms:${header.JMSDestination}</simple>
>> >> >>>>                   </recipientList>
>> >> >>>>               </when>
>> >> >>>>               <otherwise>
>> >> >>>>               <rollback markRollbackOnly="true" />
>> >> >>>>               </otherwise>
>> >> >>>>           </choice>
>> >> >>>>       </route>
>> >> >>>>
>> >> >>>> But if I change that Rollback to a Stop instead, I get
the
>>endless
>> >> >>>> external redeliveries again:
>> >> >>>>
>> >> >>>>       <route id="topics-out">
>> >> >>>>           <from uri="topic-jms:topic:projectx.>"/>
>> >> >>>>           <log message="Picked up message with id: ${id},
>> >> >>>> destinationType: ${header.DestinationEntityType}"
>> >> loggingLevel="INFO"/>
>> >> >>>>           <choice>
>> >> >>>>               <when>
>> >> >>>>                   <simple>${header.DestinationEntityType}
not in
>> >> >>>> 'FOO,BAR'</simple>
>> >> >>>>                   <log message="Detected new ${header.Name}
>>topic
>> >> >>>> message on ${header.JMSDestination} with id: ${id},
>> >>destinationType:
>> >> >>>> ${header.DestinationEntityType}" loggingLevel="INFO"/>
>> >> >>>>                   <recipientList ignoreInvalidEndpoints="false">
>> >> >>>>
>> >><simple>lc-jms:${header.JMSDestination}</simple>
>> >> >>>>                   </recipientList>
>> >> >>>>               </when>
>> >> >>>>               <otherwise>
>> >> >>>>                <stop/>
>> >> >>>>               </otherwise>
>> >> >>>>           </choice>
>> >> >>>>       </route>
>> >> >>>>
>> >> >>>> Why does rolling back prevent the unwanted message from
being
>> >> >>>> redelivered, while using "stop" causes the redelivery to
occur?
>> >> >>>> Intuitively, I would have thought it would work the opposite
>>way.
>> >> >>>> Rolling
>> >> >>>> back should put the item back on the "from" endpoint, allowing
>>it
>> >>to
>> >> be
>> >> >>>> processed again. "Stop" should just drop the message, preventing
>> >> further
>> >> >>>> redelivery. What I'm actually seeing is the opposite of
this.
>>Am I
>> >> >>>> misunderstanding?
>> >> >>>>
>> >> >>>> I also get the same exact symptoms if I leave the cache
level at
>> >> >>>> CACHE_SESSION, but I make the subscription durable. In
that case
>> >>the
>> >> >>>> rollbacks prevent the problem, but otherwise I get the
eternal
>> >> external
>> >> >>>> redeliveries.
>> >> >>>>
>> >> >>>> Using a Filter element also produces the same results as
using
>>the
>> >> >>>> Choice
>> >> >>>> element above:
>> >> >>>>
>> >> >>>>       <route id="topics-out">
>> >> >>>>           <from
>> >> >>>>
>> >>uri="topic-jms:topic:projectx.>?durableSubscriptionName=testdurasub"/>
>> >> >>>>           <log message="Picked up message with id: ${id},
>> >> >>>> destinationType: ${header.DestinationEntityType}"
>> >> loggingLevel="INFO"/>
>> >> >>>>           <filter>
>> >> >>>>               <simple>${header.DestinationEntityType}
not in
>> >> >>>> 'FOO,BAR'</simple>
>> >> >>>>               <recipientList ignoreInvalidEndpoints="false">
>> >> >>>>
>><simple>lc-jms:${header.JMSDestination}</simple>
>> >> >>>>               </recipientList>
>> >> >>>>           </filter>
>> >> >>>>       </route>
>> >> >>>>
>> >> >>>> When I look at the topic in JMS, I see the topic "projectx.>"
>> >> appearing
>> >> >>>> and disappearing in the list rapidly. I assume that's caused
by
>>the
>> >> >>>> Camel
>> >> >>>> polling frequency. It seems a little disturbing to me;
is that
>> >>normal?
>> >> >>>>
>> >> >>>> Thanks so much for taking the time to help!
>> >> >>>>
>> >> >>>> Jeff Bischoff
>> >> >>>> WDTS
>> >> >>>
>> >> >>
>> >> >
>> >> > ________________________________
>> >> >
>> >> > Please take note: This email, including attachments, contains
>> >> information which may be confidential or legally privileged and is
>>only
>> >>for
>> >> the use of the individual or entity to whom it is properly addressed.
>> >>Any
>> >> unauthorized review, use, disclosure, copying, or distribution is
>> >> prohibited. If you have reason to believe that you have received this
>> >> communication in error, or that it may be misaddressed or not
>>intended
>> >>for
>> >> you, please destroy it and notify the sender immediately. Thank you.
>> >>
>> >>
>>
>> ________________________________
>>
>> Please take note: This email, including attachments, contains
>>information
>> which may be confidential or legally privileged and is only for the use
>>of
>> the individual or entity to whom it is properly addressed. Any
>>unauthorized
>> review, use, disclosure, copying, or distribution is prohibited. If you
>> have reason to believe that you have received this communication in
>>error,
>> or that it may be misaddressed or not intended for you, please destroy
>>it
>> and notify the sender immediately. Thank you.
>>

________________________________

Please take note: This email, including attachments, contains information which may be confidential
or legally privileged and is only for the use of the individual or entity to whom it is properly
addressed. Any unauthorized review, use, disclosure, copying, or distribution is prohibited.
If you have reason to believe that you have received this communication in error, or that
it may be misaddressed or not intended for you, please destroy it and notify the sender immediately.
Thank you.

Mime
View raw message