Question

Is there a way to propagate MULE_CORRELATION_ID in a message that goes through different JMS queues. I tried OUTBOUND, SESSION scopes in <message-properties-transformer> element but doesn’t work. Same holds true for other custom properties as well.

As a workaround, I’m forced to add message property in intermediary flows.

It looks like outbound properties end up in the inbound scope for the receiving endpoint. Can we configure this behavior

Sample Mule flow:

<flow name="proxyService">
    <http:inbound-endpoint address="${xxx.service.address}"
        exchange-pattern="request-response">
        <cxf:proxy-service wsdlLocation="classpath:xxx.wsdl"
            namespace="http://xxxx.com/services/abc" service="ABCService" />
    </http:inbound-endpoint>

    <component class="com.xxxx.services.xxx.ABCServiceProxy" />
    <choice>
        <when evaluator="xpath" expression="fn:local-name(/*/*[1])='blah'">             
            <choice>                    
                <when evaluator="xpath"
                    expression="//acord:TXLifeRequest/acord:TransType/@tc='121'">                       
                    <!-- this is asynchronous communication using correlation id -->
                    <message-properties-transformer scope="outbound">
                        <add-message-property key="MULE_CORRELATION_ID"
                    value="#[xpath://abc:XYZRequest/some ID]" />
                    </message-properties-transformer> 
                     <request-reply > 
                        <jms:outbound-endpoint queue="order.queue">
                            <message-properties-transformer scope="outbound">                                   <delete-message-property key="MULE_REPLYTO" />                                  
                            </message-properties-transformer>
                        </jms:outbound-endpoint>
                         <jms:inbound-endpoint queue="status.queue" />
                    </request-reply>                        
                </when>
                <when evaluator="xpath"
                    <!-- other cases -->
                </when>
                <otherwise>
                    <!-- create failure response -->                        
                    <jms:outbound-endpoint queue="mviq.error.queue" />
                </otherwise>
            </choice>
        </when>
        <otherwise>
            <!-- log -->
        </otherwise>
    </choice>
</flow>

<flow name="ProcessOrder">
    <jms:inbound-endpoint queue="order.queue"
        exchange-pattern="one-way" />
    <!-- Storing the payload in another variable because xslt transformer will overwrite it -->
    <set-variable variableName="xxxPayload" value="#[message.payload]" />
    <xm:xslt-transformer xsl-file="xsl/something.xslt" />
    <choice>
        <when expression="'some string'">
            <!-- Overwriting the current payload to original payload -->                <set-payload value="#[xxxPayload]" />
            <logger level="INFO"
                message="payload before pushing to EMSI queue: #[payload]" />
            <jms:outbound-endpoint queue="order.special.queue" />
        </when>
        <when expression="string 2">
            <!-- other case -->
        </when>
        <when expression="'blah">

        </when>
        <otherwise>

            <jms:outbound-endpoint queue="error.queue" />
        </otherwise>
    </choice>
</flow>


<flow name="ProcessingSpecialQueue">
    <jms:inbound-endpoint queue="order.special.queue" />

    <message-properties-transformer doc:name="Message Properties">

        <add-message-property key="MULE_CORRELATION_ID" value="#some value" />
    </message-properties-transformer>

    .... more logic


</flow>

MULE_CORRELATION_ID was set before pusing message to order.queue. Now I again need to set it in order.special.queue. Now, if I needto push message into 3rd jms queue, again need to set it.

Is there a way that set correlation id just once and expect it to be not lost in subsequent queues.

I’m using Mule 3.3.0

Answer 1

Is there a way to propagate MULE_CORRELATION_ID in a message that goes through different JMS queues.

This should be done automatically for you: if it doesn’t happen, you may well be hitting a bug. Mule version? Sample configuration that allows reproducing the issue?

It looks like outbound properties end up in the inbound scope for the receiving endpoint.

This is a feature not a bug: no way to turn this off.

EDIT I have been able to reproduce the problem with a trimmed down version of your configuration:

<jms:activemq-connector name="jmsConnector"
    specification="1.1" />

<flow name="proxyService">
    <http:inbound-endpoint address="http://localhost:8080/test" />
    <set-property propertyName="MULE_CORRELATION_ID" value="custom_cid" />
    <jms:outbound-endpoint queue="order.queue" />
</flow>

<flow name="ProcessOrder">
    <jms:inbound-endpoint queue="order.queue" />
    <logger message="--> ProcessOrder CID: #[message.correlationId]"
        level="INFO" />
    <jms:outbound-endpoint queue="order.special.queue" />
</flow>


<flow name="ProcessingSpecialQueue">
    <jms:inbound-endpoint queue="order.special.queue" />
    <logger message="--> ProcessingSpecialQueue CID: #[message.correlationId]"
        level="INFO" />
</flow>

IMO Mule is not doing the right thing here so I’ve reported the issue as a bug: http://www.mulesoft.org/jira/browse/MULE-6577