ICEC-tutorial-Processes Modelling

Yany

Description

Formal Methods For Web Service Process ModelingDr. Yuhong YanNRC-IIT-FrederictonInternet LogicWeb Service StackProcess BPEL4WS, WSCI, WS-CDLDiscovery UDDIDescription WSDLXML messaging XML-RPC, SOAP, XMLTransport HTTP, SMTP, FTP, BEEP1ICEC 2006 Tutorial on SOA13-Aug-06Web Service Process Description Languages Orchestration language: BPEL4WS Choreograph languages: WS-CDL, WSCI Formal models: Process Algebras, Petri nets, Automata2ICEC 2006 Tutorial on SOA13-Aug-06Modeling and Reasoning about Web Service Processes How to model the control flow and data flow What are the reasoning tasks What are the techniques for these tasks3ICEC 2006 Tutorial on SOA13-Aug-06Web Service Process vs. Workflow Management Workflow management– Hybrid system of human and software applications– Collaborative working environment – Workitems-actors– Process descriptions similar to orchestration languages Web services– Automated services– Interoperation and service oriented architecture– request-response– Web service process engine can be similar to workflow management engine (cf. Karagiannis 2006)4ICEC 2006 Tutorial on SOA13-Aug-06Business Process Execution Language for Web Service5ICEC 2006 Tutorial on SOA13-Aug-06Business Process Execution Language for Web Service (BPEL4WS)The information described by BPEL4WS: The execution ...

Informations

• Publié par: Licod
• Nombre de lectures: 40
• Langue: English

Extrait

Formal Methods For Web Service Process Modeling

Dr. Yuhong Yan

NRC-IIT-Fredericton

Internet Logic

1

Web Service Stack

Process BPEL4WS, WSCI, WS-CDL

Discovery UDDI

Description WSDL

XML messaging XML-RPC, SOAP, XML

Transport HTTP, SMTP, FTP, BEEP

ICEC 2006 Tutorial on SOA

13-Aug-06

2

Web Service Process Description Languages

  

Orchestration language: BPEL4WS Choreograph languages: WS-CDL, WSCI Formal models: Process Algebras, Petri nets, Automata

ICEC 2006 Tutorial on SOA

13-Aug-06

3

Modeling and Reasoning about Web Service Processes

  

How to model the control flow and data flow What are the reasoning tasks What are the techniques for these tasks

ICEC 2006 Tutorial on SOA

13-Aug-06

4

Web Service Process vs. Workflow Management

 Workflow management – Hybrid system of human and software applications – Collaborative working environment – Workitems-actors – Process descriptions similar to orchestration languages  Web services – Automated services – Interoperation and service oriented architecture – request-response – Web service process engine can be similar to workflow management engine (cf. Karagiannis 2006)

ICEC 2006 Tutorial on SOA

13-Aug-06

5

Business Process Execution Language for Web Service

ICEC 2006

Tutorial

on SOA

13-Aug-06

6

Business Process Execution Language for Web Service (BPEL4WS)

The information described by BPEL4WS:

 Theexecution orderof theactivities  Thetriggering conditionsof theacvitiesti  Thepartnersfor the external activities  Thecompositionof Web Services  Thebindingto WSDL (activities <-> operations)

ICEC 2006 Tutorial on SOA

13-Aug-06

Business Process (what) versus WSDL (how)

WSDL portType

Business Process:whatto do • Modeled as a sequence of activities • Tools aid to define, monitor, and manage business processes

1

2 3

WSDL:howto execute activities • An activity can be an internal or   external Web service (SOAP/WSDL) • A business process can be exposed for consumption by another business process 7 process or a client app ICEC 2006 Tutorial on SOA

uBisness 

A

C E

Dynamic Partner/ Service Selection

B

D

Etxenrla 

Service 13-Aug-06

8

How BPEL looks like?

<processname="echoString" targetNamespace="urn:echo:echoService" xmlns:tns="urn:echo:echoService" xmlns="http://schemas.xmlsoap.org/ws/2003/03/business-process/">

<partnerLinks> <partnerLinkname="caller" partnerLinkType="tns:echoPLT"   myRole="service"/> </partnerLinks>

<variables> <variable name="request" messageType="tns:StringMessageType"/> </variables>

<sequencename="EchoSequence"> <receivepartnerLink="caller" portType="tns:echoPT" operation="echo"variable="request" createInstance="yes"name="EchoReceive"/> <replypartnerLink="caller" portType="tns:echoPT" operation="echo"variable="request"name="EchoReply"/> </sequence>

</process>

ICEC 2006 Tutorial on SOA

13-Aug-06

9

BPEL activities



Basic Activities: atomic actions – <receive> – <reply> – <invoke> – <assign>   – <throw> – <terminate> – <wait> – <empty>

ICEC 2006 Tutorial on SOA

13-Aug-06

10

BPEL Structured Activities

 <sequence>: an ordered sequence of activties  <flow>: parallel activities  <switch>: “case-statement” approach  <while>: loop  <pick>: execute one of several alternative paths

ICEC 2006 Tutorial on SOA

13-Aug-06