Overview

Disclaimer:
Throughout this document - even we have a single process engine with version 7.5 - we use the former product names, features, or capabilities when we talk about the interaction of both engines for better differentiation understanding for people having worked with the one or other system.

The integration of a WPS BPEL - and WLE processes can be achieved via existing Web Service technology. However, the new integration capability offered with version 7.5 is the support of the Service Component Architecture (SCA) standard by WLE. The SCA integration between WPS and WLE is explained, demonstrated and executed with the sample documented in the exercise. You should notice, that there is a similar document available for a so called human-centric scenario, where a WLE process calls a BPEL process to provide some kind of automated / integration service. Refer to the advanced hiring sample which demonstrates the use of an Advanced Integration Service (AIS) in a BPD to invoke a SCA service component.

The development of a solution demonstrating the interaction of two process engines involves the development of processes by two user roles (personas). First, the Business Author or Process Designer named Bob, who uses the IBM Process Designer (IPD), former known as Lombardi Authoring Environment (AE). Second, the IT Developer or Integration Specialist named Igor, who uses the IBM Integration Designer (IID), former known as WebSphere Integration Designer (WID). IID was enhanced in such a way that it provides a new perspective named Process Center perspective. This allows to interact with, synchronize with, and retrieve artifacts from the Process Center by several developers for a given project rather having the project stored locally in a developers WID workspace. The Process Center is the central repository to store, access, and manage process artifacts hold together in a single project called a process application.

The STP scenario, same for the human-centric one, can be build in three ways:

A. Bob starts with the development of the BPD and Igor assist in providing the BPEL process from scratch. This is known as STP top-down scenario.

B. Igor starts with the development in IID and Bob develops his part of the solution in IPD. This is known as STP bottom-up scenario.

C. A process application with a BPD and a WPS module with a BPEL process exist already and work on their own. This is called a meet-in-the-middle scenario.

In B. or C. you need to re-factor business objects or use mediation flow components (MFC) with interface and BO maps. The top-down approach is somehow easier and briefly mentioned in the document, whereas the focus is with the bottom-up approach B.

Even this document describes the development and integration steps in much detail it is assumed that the reader is somehow familiar with the modeling concepts developing BPEL processes and BPDs. So this scenario will start with an initial BPEL process provided and demonstrate in detail the SCA integration with a BPD. For samples on how to develop BPEL processes refer to http://publib.boulder.ibm.com/bpcsamp/index.html. On material on how to build Lombardi process refer to http://publib.boulder.ibm.com/infocenter/wle/v7r1/index.jsp?topic=/wle/common/topic/starting_ae.html .

The document on hand will also introduce some settings not necessarily required for the SCA integration but for the execution and user interaction using Business Space, e.g. the federated client.

The document will not cover

• best practices for the integration of a WLE human-centric flow or service into a BPEL process
• using comprehensive staff assignments for the WLE human tasks.

Exception Handling in Straight Through Processing

From a positioning point of view WPS is used for automated processes and comprehensive human workflow processing is dedicated to WLE. In this scenario the WLE process with a human task in it is used for some kind of exception handling. The major steps to build this scenario are shown in the diagram below.

Development Approach

The development of a solution that consists of an integration-oriented, automated STP process with a human interaction implemented as a BPD in the Process Designer involves several steps and development artifacts that are centrally stored and shared in the Process Center.

On high level we have two user roles which interact in the development, testing, and the deployment of the process application.

Business Scenario

The development steps to build, deploy, test and run the procurement sample is performed for a business scenario of an internal replenishment order process. The process applies to the manufacturing or retail industry. When the stock for any goods falls beneath a given limit an internal order is automatically triggered. The corresponding BPEL process and its activities are shown and explained in the diagram below. As part of the activity Approve Replenishment Order the BPEL process calls a WLE BPD with a human task and coaches to request approval by an authorized user. The approval task needs to be performed in a given time. Otherwise the activity expires, the approval status is set to true, and processing completes.