Working with array in Oracle BPEL

This is an extension usage of array based from my previous post.

In the following example the variable Variable_whileLoopIteration is the iteration counter in the WHILE activity.

Reading from a specific element in an array:

<assign name="Extract_ProductName">
<copy>
<from expression="bpws:getVariableData('Variable_PurchaseOrder',concat('/ns1:purchaseOrder/ns1:items/ns1:item[',bpws:getVariableData('Variable_whileLoopIteration'),']/ns1:productName'))"/>
<to variable="Variable_productName"/>
</copy>
</assign>

Writing to a specific element in an array:

<assign name="Assign_NewProductNameToPO">
<copy>
<from expression="'NewProductName'"/>
<to variable="Variable_PurchaseOrder" query="/ns1:purchaseOrder/ns1:items/ns1:item[position() = bpws:getVariableData('Variable_whileLoopIteration')]/ns1:productName"/>
</copy>
</assign>

My advise is don't rely on JDeveloper Design view alone. Most of the time you have to manually edit the source to get it to do exactly what you want.

Looping over each nodes in Oracle BPEL

This is an example how to use WHILE loop in Oracle BPEL Process Manager 11g.

This example will be based on the JDEPurchaseOrders.xsd schema and the JDEPurchaseOrders.xml sample data.

Step 1, create another XSD to map your temporary data at for each node. Let's call it JDEPurchaseOrder.xsd.

Step 2, create variables based on the message type that contains this collection, and 2 counters, Variable_LoopRunningIndex for the running index, and Variable_LoopCounter for the length of the collection.As shown below:

    <variable name="Variable_LoopRunningIndex" type="xsd:integer"/>
    <variable name="Variable_LoopCounter" type="xsd:integer"/>
    <variable name="Variable_tempJDEPurchaseOrder" element="ns3:HEADER"/>

Step 3, initialise variables for looping.

    <assign name="Initialise_WhileLoop">
      <copy>
        <from expression="number(1)"/>
        <to variable="Variable_LoopRunningIndex"/>
      </copy>
      <copy>
        <from expression="ora:countNodes('Receive_JDEFlatfile_Read_InputVariable','body','/ns3:JDEPurchaseOrder/ns3:HEADER/ns3:ID') + 1"/>
        <to variable="Variable_LoopCounter"/>
      </copy>
    </assign> 

Step 4, implement BPEL while activity to loop over each node

    <while name="For_Each_Header_Record"
           condition="bpws:getVariableData('Variable_LoopRunningIndex') &lt; bpws:getVariableData('Variable_LoopCounter')">
      <bpelx:annotation>
        <bpelx:general>
          <bpelx:property name="userLabel">For_Each_Header_Record</bpelx:property>
        </bpelx:general>
      </bpelx:annotation>
      <sequence name="Split_Purchase_Order">
        <scope name="Scope_1">
        <!-- Declare scope variables -->
          <variables>
            <variable name="Variable_selector" type="xsd:string"/>
            <variable name="Variable_tempJDEPurchaseOrder" element="ns3:HEADER"/>
          </variables>
          <sequence name="Sequence_1">
          <!-- Map current node into temp struct -->
            <assign name="Create_tempJDEPurchaseOrder">
              <copy>
                <from expression="concat(&quot;/ns3:JDEPurchaseOrder/ns3:HEADER[&quot;, string(bpws:getVariableData('Variable_LoopRunningIndex')),&quot;]&quot;)"/>
                <to variable="Variable_selector"/>
              </copy>
              <copy>
                <from expression="bpws:getVariableData('Receive_JDEFlatfile_Read_InputVariable','body', bpws:getVariableData('Variable_selector'))"/>
                <to variable="Variable_tempJDEPurchaseOrder"/>
              </copy>
            </assign>
            <!-- Transform temp struct required output -->
            <assign name="XForm_tempJDEPurchaseOrder_to_EDIFACT">
              <bpelx:annotation>
                <bpelx:pattern>transformation</bpelx:pattern>
              </bpelx:annotation>
              <copy>
                <from expression="ora:processXSLT('xsl/XForm_tmpJDEPurchaseOrder2EDIFACT.xsl',bpws:getVariableData('Variable_tempJDEPurchaseOrder'))"/>
                <to variable="SendPurchaseOrder_send_InputVariable"
                    part="body"/>
              </copy>
            </assign>
            <!-- Send output to B2B to dispatch -->
            <invoke name="SendPurchaseOrder"
                    inputVariable="SendPurchaseOrder_send_InputVariable"
                    partnerLink="DispatchPurchaseOrder"
                    portType="ns2:B2B_send_ptt" operation="send">
              <bpelx:inputProperty name="b2b.documentProtocolVersion"
                                   variable="Variable_documentProtocolVersion"/>
              <bpelx:inputProperty name="b2b.documentTypeName"
                                   variable="Variable_documentTypeName"/>
              <bpelx:inputProperty name="b2b.toTradingPartnerId"
                                   variable="Variable_toTradingPartnerId"/>
            </invoke>
          </sequence>
        </scope>
        <!-- Increment the index and repeat next node -->
        <assign name="Increment_LoopRunningIndex">
          <copy>
            <from expression="bpws:getVariableData('Variable_LoopRunningIndex') + 1"/>
            <to variable="Variable_LoopRunningIndex"/>
          </copy>
        </assign>
      </sequence>
    </while> 

Debugging Oracle BPEL process using Sensors in 11g

Sensor is a great feature if you want customise audit trail or debug BPEL processes. The following use case is logging a custom audit message after a transformation BPEL activity has finished, the steps are as follows:

1. Open the composite application

2. Go into your BPEL process

3. Add a new variable called "AuditMessage"

4. Populate value for AuditMessage, in this case I want to set "ReadMessage process step completed successfully." message to the AuditMessage at ReadMessage process step.

5. Change to Monitor View

6. Create sensor at the ReadMessage process step

7. Label the sensor as "ActivitySensor_ReadMessage"

8. Set evaluation time at Completion

9. Create activity variable sensor

10. Create sensor action

11. Sensor is illustrated with an antena icon

12. Save and deploy your composite application

13. Run your composite application
14. Logon to Oracle Enterprise Manager and navigate to SOA Infra

15. Click on the Instance ID

16. Click on the BPEL component

17. Navigate to Sensor Values tab

Further reading:

• Debug logging in BPEL using sensors for 10g by Peter Ebell
• Using Oracle BPEL Process Manager Sensors by Oracle Fusion Middleware Developer's Guide