Mule Routing Choice based on Flow Variable Value

Question

I have a Mule sub flow with a possibly two outbound JMS queues. When I use MEL to make a choice based on header values, my messages end up in one queue as if MEL is not even executed:

<sub-flow name="enqueueFlow">
    <!--logger message="Message inbound #[message.inboundProperties['myheader']]" doc:name="Test Flow logging" level="INFO"/--> 
    <choice doc:name="QueueChoice">
        <when expression="#[message.inboundProperties['myheader'] != null and message.inboundProperties['myheader'] == 'urgent']">
            <set-variable variableName="queueName" value="${urgentQueueName}" doc:name="queueName"/>
        </when>
        <otherwise>
            <set-variable variableName="queueName" value="${lowPriorityQueueName}" doc:name="queueName"/>
        </otherwise>
    </choice>
    <!--logger message="Deposit message into queue named #[variable:queueName]" doc:name="Test Flow logging" level="INFO"/-->       
    <jms:outbound-endpoint queue="#[variable:queueName]"
                        connector-ref="EnqueueJmsConnector"> 
    </jms:outbound-endpoint>
</sub-flow>

Answer 1

In the jms:outbound-endpoint, use #[queueName] instead of #[variable:queueName]

Also no need to use a choice router to emulate a ternary expression, just use:

<set-variable variableName="queueName"
    value="#[h = message.inboundProperties['myheader']; h == empty || h != 'urgent' ? '${lowPriorityQueueName}' : '${urgentQueueName}']"/>