CODEWITHSUNDEEP
wso2wso2-esbwso2-enterprise-integratorwso2-integration-studio
Ruby
Ruby

Reputation: 378

Nested Iterate Mediator is not working in WSO2 esb

{"methods":[[{"p_id":"v1","offline":false,}],[{"p_id":"v2","offline":true,}]]}

The above is my JSON payload. I am making use of nested Iterate mediators to fetch the values of p_id and v1. I am able to fetch the values successfully, but the logs outside the first iterate mediator are not getting printed.

Following is my code:

<iterate expression="json-eval($.methods)" id="iterate-over-Methods">
    <target>
        <sequence>
            <iterate expression="json-eval($)" id="2nd-iteration">
                <target>
                    <sequence>
                        <filter regex="false" source="json-eval($.offline)">
                            <then>
                                <property expression="json-eval($.p_id)" name="p-id" scope="default" type="STRING"/>
                                <log>
                                    <property expression="$ctx:p-id" name="p-id-set"/>
                                </log>
                            </then>
                            <else>
                                <log>
                                    <property name="p-id-set" value="Provider ID already set"/>
                                </log>
                            </else>
                        </filter>

                        <log>
                            <property name="status-1" value="Inside 1st iteration" />
                        </log>
                    </sequence>
                </target>
            </iterate>
            <log>
                <property name="status-2" value="Inside 2nd iteration" />
            </log>
        </sequence>
    </target>
</iterate>

Is the code going into some infinite loop that it is not coming out? How can I handle this? Thanks in advance..

Upvotes: 2

Views: 440

Answers (1)

ycr
ycr

Reputation: 14574

From the information you provided I think you can use a single Iterator here.(But this really depends on your full usecase). Here is a sample with a single Iterate Mediator.

<iterate expression="json-eval($.methods)" id="pl-iterator">
    <target>
        <sequence>
            <property expression="json-eval($[0].p_id)" name="p-id" scope="default" type="STRING"/>
            <log level="full">
               <property expression="$ctx:p-id" name="p-id-set"/>
            </log>
        </sequence>
    </target>
</iterate>

Also, an Iterate Mediator should be coupled with an Aggregate Mediator. So make sure you add appropriate aggregation logic as well.

Iterate mediator should not be considered as a for-loop in programming languages. When you Iterate over a payload, the Payload will be split and each segment will concurrently execute on its own thread. So having nested Iterate Mediators is not a good idea unless it's really necessary.

Upvotes: 3

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