Camunda is an open source BPM tool which has been forked from Activiti. Some of the differences between Activiti and Camunda, as well as advantages of using Camunda, may be found here and here.

After spending some time testing out Camunda, I decided to include a Mule call from within a Camunda process. This would be useful when designing processes which require information from external components, so as to be able to leverage Mule’s connectivity.

I decided to start with Camunda’s very good quick start guide, where you will be able to get a simple BPM process running in no time.

The following depicts the BPMN process for this example where a customer applies for a loan and this is to be approved. The service task points to the class “ProcessRequestDelegate” which is executed when processing the request:

Below is the processRequestdelegate class which makes an HTTP call to Mule via the Mule Client:

public class ProcessRequestDelegate implements JavaDelegate {

	private final static Logger LOGGER = Logger.getLogger("LOAN-REQUESTS");

	public void execute(DelegateExecution execution) throws Exception {
		LOGGER.info("Processing request by '"
				+ execution.getVariable("customerId"));

		// make rest call to mule	
		MuleClient client = new MuleClient(true);
		MuleMessage result = client.send("http://localhost:8082/mule/", "Message Payload", null);
		LOGGER.info("Result from mule is: " + result.getPayloadAsString());
	}
}

The following are two dependencies required in the Camunda application pom.xml file in order to make an HTTP Mule client call to Mule:

In Mule, a simple flow with an inbound HTTP endpoint has been created. This flow may be used to request any required information from external components.