142 Broker Interactions for Intra- and Inter-enterprise
7.7.1 Flow Definition Language
Flow Definition Language (FDL) is a text based process definition format that
provides an interface between process modeling and development tools, and the
process engine of WebSphere MQ Workflow.
An FDL document describes the make-up of a process flow. Although
theoretically FDL could be written by hand, it is commonly generated using
WebSphere MQ Workflow Buildtime. As FDL became an established standard,
other process modeling and development tools came on the market that were
capable of exporting FDL, thus suitable for use with WebSphere MQ Workflow.
This included third parties such as Holosofx®, who have since been acquired by
IBM. The Holosofx product is now marketed as IBM WebSphere Business
Integration Workbench, and offers facilities to generate FDL.
7.7.2 Flow Definition Markup Language
Despite its name, which sounds similar to FDL, Flow Definition Markup
Language (FDML) is actually based on the Web Services Flow Language
(WSFL) standard introduced by IBM. FDML introduces extensions to the WSFL
standard and is the flow language used to describe a WebSphere Process
Choreographer process.
WebSphere Studio Application Developer Integration Edition uses FDML to
describe WebSphere Process Choreographer business processes.
FDML describes the behavior of the process. It is an XML based format. An
FDML file describes elements of a process such as the flow model, activities,
control links, compensation, messages, and variables.
A sample of an FDML file is shown in Example 7-1.
Example 7-1 Sample FDML file
wf:flowModel autoDelete="true" canRunInterrupted="true"
canRunSynchronous="false" name="EventCompensationProcess"
requiresCompensationSphere="true" validFrom="2003-01-01T12:00:00">
<wf:messageType name="MessageType_11" typeSystem="WSDL2">
<service:messageRef name="processOrderInput"
namespace="http://process.itso.ibm.com/">
<service:import
location="file:com/ibm/itso/process/EventCompensationProcessInterface.wsdl"/>
</service:messageRef>
</wf:messageType>
For more information about FDML, please refer to the IBM Redbook WebSphere
Version 5 Web Services Handbook, SG24-6891.