Book Image

Business Process Execution Language for Web Services

Book Image

Business Process Execution Language for Web Services

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

Importing BPEL Processes into BizTalk


Importing BPEL processes into BizTalk is quite easy. BizTalk provides a separate project template called the BizTalk Server BPEL Import Project, which will bring up a wizard to take you through the BPEL import procedure step by step. However, there are a few things you need to take care of before importing business processes:

  • Ensure that the Name property of the WSDL definition node and that of the BPEL process node are not the same.

  • Do not use any XLANG/s reserved words in your BPEL.

  • Use only simple types predefined in XSD.

Now let us use the asynchronous travel process example we saw in Chapter 3 to import into BizTalk and see how it goes.

But before we do that we need to make a few modifications to the .wsdl files. The .wsdl files (Travel.wsdl, Airline.wsdl, and Employee.wsdl) used in the travel process example in Chapter 3 uses the RPC style, whereas BizTalk currently does not support the RPC style and requires that the .wsdl files be in Document style...