Book Image

Business Process Execution Language for Web Services 2nd Edition

Book Image

Business Process Execution Language for Web Services 2nd Edition

Overview of this book

Web services provide the basic technical platform required for application interoperability. They do not, however, provide higher level control, such as which web services need to be invoked, which operations should be called and in what sequence. Nor do they provide ways to describe the semantics of interfaces, the workflows, or e-business processes. BPEL is the missing link to assemble and integrate web services into a real business process BPEL4WS standardizes process automation between web services. This applies both within the enterprise, where BPEL4WS is used to integrate previously isolated systems, and between enterprises, where BPEL4WS enables easier and more effective integration with business partners. In providing a standard descriptive structure BPEL4WS enables enterprises to define their business processes during the design phase. Wider business benefits can flow from this through business process optimization, reengineering, and the selection of most appropriate processes . Supported by major vendorsó including BEA, Hewlett-Packard, IBM, Microsoft, Novell, Oracle, SAP, Sun, and othersó BPEL4WS is becoming the accepted standard for business process management. This book provides detailed coverage of BPEL4WS, its syntax, and where, and how, it is used. It begins with an overview of web services, showing both the foundation of, and need for, BPEL. The web services orchestration stack is explained, including standards such as WS-Security, WS-Coordination, WS-Transaction, WS-Addressing, and others. The BPEL language itself is explained in detail, with Code snippets and complete examples illustrating both its syntax and typical construction. Having covered BPEL itself, the book then goes on to show BPEL is used in context. by providing an overview of major BPEL4WS servers. It covers the Oracle BPEL Process Manager and Microsoft BizTalk Server 2004 in detail, and shows how to write BPEL4WS solutions using these servers.
Table of Contents (14 chapters)
Business Process Execution Language for Web Services
Credits
About the Authors
About the Reviewers
Preface
Index

Advanced BPEL Functions using BizTalk


Listen Shape (<pick>, <onMessage>, <onAlarm>)

A Listen shape is used when you have to receive a message before proceeding further and also need to specify a timeout period until which BizTalk waits for the message. The Listen shape can have any number of branches each starting with a Receive shape or a Delay shape. Note that you can have all branches starting with a Receive shape in which case there is no timeout period. Alternatively you can have only one branch starting with a Delay shape and the rest must start with a Receive shape. The Listen shape is equivalent to the <pick>, <onMessage>, and <onAlarm> activities of BPEL.

Scope Shape (<scope>)

A Scope shape in BizTalk is used to do the following:

  • Transaction handling

  • Synchronized access to shared data

  • Exception handling

A Scope shape has a Boolean Synchronized property, which indicates to BizTalk that all read and write operations on shared data from within the...