ServiceMix OSWorkflow

The ServiceMix OSWorkflow component provides workflow functionality to the ESB. You can specify one or more workflows and it's processing will start when a valid message is received.

If you have no experience with the OSWorkflow itself, then it would be a good idea to have a look at the website http://www.opensymphony.com/osworkflow/ and reading the documentation and tutorials there.

Maven Archetype

You can use Maven servicemix-osworkflow-service-unit archetype to create a service unit:

mvn archetype:create \
    -DarchetypeGroupId=org.apache.servicemix.tooling \
    -DarchetypeArtifactId=servicemix-osworkflow-service-unit \
    -DarchetypeVersion=2010.01 \
    -DgroupId=your.group.id \
    -DartifactId=your.artifact.id \
    -Dversion=your-version

This will give you a simple workflow example to start with.

<dir>
|--- src
     |--- main
          |--- java
          |    |--- ExampleFunction.java
          |    |--- ExampleCondition.java
          |--- resources
               |--- exampleflow.xml
               |--- osworkflow.xml
               |--- workflows.xml
               |--- xbean.xml

Endpoint Configuration

The endpoint will receive messages from the NMR and will start then the processing of the workflow. You
can send both, InOnly and InOut messages to this endpoint. Sending an InOnly message will start the workflow in
a separate thread, while sending an InOut will result in sychronous processing of the workflow.

<osworkflow:endpoint service="test:workflow"
                       endpoint="workflowEndpoint"
                       action="1"
                       caller="callerName"
                       workflowName="testflow" />

Name	Type	Description	Required
service	QName	the service name of the exposed jbi endpoint	yes
endpoint	String	the endpoint name of the exposed jbi endpoint	yes
action	String	the initial action called in workflow (must be a int value)	yes
caller	String	if set, this will be set as the caller user name of the workflow	no
workflowName	String	the name of the workflow to start. This name must be specified in workflows.xml	yes

For all xbean file endpoint configuration take a look at Xml schemas

TransientVars

To help you working with this component, there are several variables predefined in the transientVars.

Key-Constant	Value-Type	Value-Description
OSWorkflow.KEY_EXCHANGE	MessageExchange	the message exchange which was received before this workflow was started
OSWorkflow.KEY_IN_MESSAGE	NormalizedMessage	the "in" message which was received before this workflow was started
OSWorkflow.KEY_ENDPOINT	OSWorkflowEndpoint	the endpoint managing this workflow (provides useful helper methods)
OSWorkflow.KEY_CALLER	String	The caller user name defined in the endpoints configuration (caller in xbean)
OSWorkflow.KEY_ASYNC_PROCESSING	Boolean	if true, the workflow is running in a separate thread

You are completly responsible for doing the message handling. If you received a InOnly exchange for example, you have to set it's state to DONE yourself. Also when working with InOut exchanges you have to send the answer yourself in the workflow. For the error handling it's the same.