Facing error in Batch Processing mule esb

Question

I am facing problem in batch processing mule esb. If I set any payload in process record face and try to get that payload in oncomplete face then not getting that payload. same problem with variable and property. If I set any property in process record phase and try to get in on complete phase then always get null value. how to get those value in oncomplete phase? below is flow..

<batch:job name="TestBatch" max-failed-records="-1">
        <batch:input>

            <component class="com.test.RecordTest"
            doc:name="Java" />
        <json:object-to-json-transformer
            doc:name="Object to JSON" />
        <custom-transformer class="com.test.CustomTr"
            doc:name="Java" />
        </batch:input>
        <batch:process-records>
            <batch:step name="Batch_Step1" accept-policy="ALL">
                <batch:commit size="5" doc:name="Batch Commit">
                <!-- Insert record in Salesforce  -->
                </batch:commit>
            </batch:step>
            <batch:step name="Batch_Step2" accept-policy="ONLY_FAILURES">
                <logger message="STEPP #[getStepExceptions()]" level="INFO" doc:name="Logger"/>
                <set-property propertyName="error" value="STEPP #[getStepExceptions()]" doc:name="Property"/>
                <set-payload value="#[getStepExceptions()]" doc:name="Set Payload"/>

            </batch:step>

        </batch:process-records>
        <batch:on-complete>
            <logger level="INFO" doc:name="Logger" message="--&gt;  #[payload.failedRecords] --&gt;  #[message.payload] "/>
            <logger message="error--- #[message.outboundProperties['error']] " level="INFO" doc:name="Logger"/>

        </batch:on-complete>
    </batch:job>

I got null in property logger

How can I solve this?

Answer 1

I got some bad news from you :-). Batch processing by design will not old any of the value you may try to set in steps, especially payload.

When I started working with it I was also expecting to have session variable on complete phase in a correct status but this is not the case, they are completely wiped at each step.

Now I don't think this is a bug, but it is really a design feature that I can understend even if I don't really love it. I solved the same problem by using the object store connector.

It will allow you to access the mule Object Store API via nice XML configuration block, in this way you can store in memory variables that you can recover after in your on-complete without them being affected by flow logic.

Hope this helps