1. 1 CSIT600c: Web Services Programming Workflow and BPEL4WS Dickson K.W. Chiu PhD, SMIEEE Thanks to Dr. Patrick C.K. Hung (UOIT)

2. Dickson Chiu 2005CSIT600c 02-2 An Illustrative Example Many airline companies have Web sites with information about their services, e.g., flight schedules Finding flight and fare information is not simple in automatic business-to-business (B2B) applications Ref: SELVIDGE, P. 1999. Student posters: Reservations about the usability of airline web sites Paula Selvidge, CHI '99 extended abstracts on Human factors in computing systems

3. Dickson Chiu 2005CSIT600c 02-3 Proprietary protocol and interface http://www.cathaypacific.com/intl/plan/schedules/result/0, 3845,,00.html?WAtxn=202&fromShortCut=&language=G B&device=web&tripType=2&d_city=HKG&a_city=BOS& d_month=200502&d_day=25&r_month=200503&r_day= 29&cabins=&errorListIndex=&errorList= http://www.itn.net/cgi/air?stamp=NEWCOOKY*itn%2Ford %3DNEWREC,itn/air/united&airline=United&persons=1& air_avail=10&air_class=coach+%28lowest+avail.%29&de part=hkg&dest.0=bos&mon_abbr.0=Feb&date.0=25&hou r_ampm.0=5+am&mon_abbr.1=Mar&date.1=29&hour_a mpm.1=5+am&ecert_num=&rt_ow=Round+Trip&best_iti ns=2&return_to=best_itins&searchby=itins Adapted from: http://www.cathaypacific.com Adapted from: http://www.united.com

4. Dickson Chiu 2005CSIT600c 02-4 Proprietary result format Adapted from: http://www.cathaypacific.comAdapted from: http://www.united.com

5. Dickson Chiu 2005CSIT600c 02-5 Airline C Airline AAirline B Internet Check Flight Schedules Web Service B2B Applications Travel Agency Decision Making Compare Options Check Flight Schedules Check Flight Schedules IBM WebSphere Sun Java Microsoft.Net Business Process Example (Travel Agency)

6. Dickson Chiu 2005CSIT600c 02-6 Roadmap to deploy Web Services Standards (e.g. travel agency)

7. Dickson Chiu 2005CSIT600c 02-7 Roadmap to deploy Web Services Standards (cont.)

8. Dickson Chiu 2005CSIT600c 02-8 Workflow and Business Process Workflow is a computer supported business process A business process contains a set of activities which represent both business tasks and interactions between Web services Can be traced from the earlier imaging solutions space – document workflow Early workflow products enabled the automation of human administrative activities very well. The need for coordinating Web services for different business processes in a loosely coupled business-to-business environment Now we need to manage end-to-end business process encompasses both human and system interactions. Business Process Management (BPM) deals with broader issues of ensuring continuous business process improvements Business process analysis and re-design Business process implementation Business process monitoring

9. Dickson Chiu 2005CSIT600c 02-9 Workflow Management Coalition (WfMC) Non-profit, international organization of workflow vendors, users, analysts and university/research groups that promotes workflow interoperability standards. Workflow Reference Model http://www.wfmc.org

10. Dickson Chiu 2005CSIT600c 02-10 Web Service Business Process Languages Need a language to define a model and a grammar for describing the behavior of a business process based on interactions between the process and its Web service interfaces. Business process definition can be thought of as a template for creating business process instances. All of the proposed XML workflow languages are based on WSDL service descriptions with extension elements such as: Business Process Execution Language for Web Services (BPEL4WS) Web Services Flow Language (WSFL) and Web Services Endpoint Language (WSEL) XLANG Ref: Business Process Execution Language for Web Services, Version 1.1, 05 May 2003. http://www- 106.ibm.com/developerworks/library/ws-bpel/

11. Dickson Chiu 2005CSIT600c 02-11 BPEL4WS Proposed by IBM and Microsoft Reference: http://www.redbooks.ibm.com/redpieces/abstracts/sg246381.html http://www.redbooks.ibm.com/redpieces/abstracts/sg246381.html

12. Dickson Chiu 2005CSIT600c 02-12 Business Process Diagram Receive Customer’s Request Reply to Customer (Results) Invoke Airline B’s Web service Invoke Airline A’s Web service Invoke Airline C’s Web service

13. Dickson Chiu 2005CSIT600c 02-13 BPEL4WS Listing

14. Dickson Chiu 2005CSIT600c 02-14 partnerLinks: It defines the different parties that interact with the business process in the course of processing the order. BPEL4WS – Partner Links

15. Dickson Chiu 2005CSIT600c 02-15 variables: It defines the data variables used by the process, providing their definitions in terms of WSDL message types. BPEL4WS - variables

16. Dickson Chiu 2005CSIT600c 02-16 flow: It specifies one or more activities to be performed concurrently. Links: It can be used within concurrent activities to define arbitrary control structures. BPEL4WS – flow and links

17. Dickson Chiu 2005CSIT600c 02-17 received: It allows the business process to do a blocking wait for a matching message to arrive. BPEL4WS - received

18. Dickson Chiu 2005CSIT600c 02-18 invoke: It allows the business process to invoke a one- way or request-response operation on a portType offered by a partner. BPEL4WS - invoke

19. Dickson Chiu 2005CSIT600c 02-19 assign: It can be used to update the values of variables with new data. An construct can contain any number of elementary assignments. BPEL4WS - assign

20. Dickson Chiu 2005CSIT600c 02-20 BPEL4WS (cont.)

21. Dickson Chiu 2005CSIT600c 02-21 reply: It allows the business process to send a message in reply to a message that was received through a. BPEL4WS - reply

22. Dickson Chiu 2005CSIT600c 02-22 Input Message Output Message Web Service BPEL4WS – scenerio summary Receive Customer’s Request Reply to Customer (Results) Invoke Airline B’s Web service Invoke Airline A’s Web service Invoke Airline C’s Web service The combination of a and a forms a request-response operation on the WSDL portType for the process.