Apache Camel/ActiveMQ priority route

Question

I have two AMQ queues that have the same consumers. The first queue (Q1) handles 97% of the messages and the other (Q2) only 3%. Problem is that messages in Q2 need to process messages as soon as they are queued. So my problem is that when a message is available in Q2 I need somehow to suspend the first route to take it's consumers. The apache camel routing looks like this:

<route id="q1">
    <from uri="jms:recordAnalysisRequests" />
    <to uri="bean:analysisService" />
</route>
<route id="q2">
    <from uri="jms:recordAnalysisRequestsFastTrack" />
    <to uri="bean:analysisService" />
</route>

What strategy should use? I don't think I can use resequencer because Q1 could have thousands of messages queued up and I cannot fit all in a resequencer batch. I was looking at the route throttling but I cannot figure out how to do it. Also I was wondering if I can synchronize through a zookeeper node. Again I will need some guidance here if this solution is viable.

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G Quintana G Quintana · Accepted Answer · 2014-04-10T10:15:12

You could place all messages in a single queue and use message priority http://activemq.apache.org/how-can-i-support-priority-queues.html

Second option, use a Camel Resequencer

<route id="q1">
    <from uri="jms:recordAnalysisRequests" />
    <setHeader headerName="CustomPriority">
       <constant>2</constant>       
    </setHeader>
    <to uri="direct:analysisDirect" />
</route>
<route id="q2">
    <from uri="jms:recordAnalysisRequestsFastTrack" />
    <setHeader headerName="CustomPriority">
       <constant>1</constant>       
    </setHeader>
    <to uri="direct:analysisDirect" />
</route>
<route id="q3">
    <from uri="direct:analysisDirect">
    <resequence>
        <header>CustomPriority</header>
        <to uri="bean:analysisService" />
    </resequence>
</route>

Third option (Camel 2.12), insteads of using a resequencer, use a SEDA endpoint with a PriorityBlockingQueue https://camel.apache.org/seda.html#SEDA-ChoosingBlockingQueueimplementation

Apache Camel/ActiveMQ priority route

1 Answers