Invoke

ActiveVOS Designer User’s Guide

Invoke

The invoke activity directs a Web service to perform a one-way or request-response operation. It specifies the participant that provides the service and the operation to invoke. The invoke activity must specify the data for the message transmitted and may specify an output variable or variable part in the case of a synchronous request-response Web service invocation. See Participants for descriptions of concepts important to this activity.

An invoke activity can be compensated, or reversed, by including it in a scope structure. For more information, see Compensation.

An invoke activity can also include fault handling when the invoke is added to a scope. Alternately, any faults associated with the invoked service can be handled at the process level, if desired. For more information, see Fault Handling.

Required and optional properties for invoke
Required Properties	Optional Properties
Participant (Partner Link)	Name. See Selecting Activity Labels
Operation	Port Type
Input Variable See Input Variable. or toPart fromVariable See From Variable to Part.	Correlations. See Correlation.
	Output Variable See Output Variable. fromPart toVariable. See From Part to Variable.
	Input and Output assignments
	Suppress Join Failure. See Process Properties
	Join Condition. See Creating a Join Condition for an Incoming Link
	Comment. See Adding Comments to a Process
	Documentation. See Adding Documentation to a Process
	Setting Visual Properties and Using Your Own Library of Images
	Execution State. See Viewing the Execution State of an Activity or Link
	Extension Attributes and Extension Elements. See Declaring Extension Elements and Attributes.

To add an invoke activity to the process manually:

From the Activity palette, drag an invoke activity to the Process Editor canvas.
In the Properties view, select the following values:

Optionally type in a Name.
In the Participant drop-down, select New Partner Service Provider. See Creating a New Partner Service Interface.
Select a participant’s Operation from the drop-down list.

In the Input tab, do one of the following:

Select Single Variable from the Assignment Type and select a variable.
Select a XPaths or XQuery. For details, see Input Variable and From Part to Variable.

Optionally, select an output variable or a to part. For details, see Output Variable and From Variable to Part.
Select other optional properties as desired.

A simple example of using an invoke activity in a process is shown in the following illustration.

Invoke activity in a process

Note: For another shortcut for creating an invoke activity, see Creating an Activity by Starting with a WSDL Interface.

XML Syntax

<invoke partnerLink="NCName" portType="QName"?

     operation="NCName"

    inputVariable="NCName"? outputVariable="NCName"?

    standard-attributes>

  standard-elements

  <correlations>?

    <correlation set="NCName" initiate="yes|join|no"?

     pattern="request|response|request-response"/>+

  </correlations>

  <catch faultName="QName"? faultVariable="NCName"?

     faultMessageType="QName"? faultElement="QName"?>*

    activity

  </catch>

  <catchAll>?

    activity

  </catchAll>

  <compensationHandler>?

    activity

  </compensationHandler>

  <toParts>?

   <toPart part="NCName" fromVariable="BPELVariableName"/>+

  </toParts>

  <fromParts>?

   <fromPart part="NCName" toVariable="BPELVariableName"/>+

  </fromParts>

</invoke>

Example:

 <invoke name="invokeapprover" partnerLink="approver"

 portType="lns:loanApprovalPT" operation="approve"

 inputVariable="request" outputVariable="approval">