Can one Corticon Decision Service call another decision service?
Yes. Of Course! (a decision service can even call itself!)
But this will require a little java programming.
see attachment for an example
You will have to use either an extended operator or a service call out in order to call one Corticon decision service from another.
The extended operator approach means you can call out to Corticon either as an action or as a condition in a rule sheet.
If you use a service call out then the invocation of the decision service will occur between two rule sheets - in the rule flow diagram.
The attachment contains an example of the java code necessary to make an in-process call to Corticon.
The operator would appear in the Corticon Studio Rule Operator tab.
Then you can use it in a condition or action of a rule sheet.
You would construct the Corticon SOAP payload something like this
<CorticonRequest decisionServiceName="Skydiver"> <WorkDocuments><Applicant> <age>20</age><isSkydiver>true</isSkydiver> </Applicant> </WorkDocuments></CorticonRequest>
The result would come back like this:
<?xml version="1.0" encoding="UTF-8"?>
<text>Applicants who skydive have a High Risk rating.</text>
<entityReference href="#Applicant_id_595945461" />
This approach does however require that you construct the SOAP message somehow (either by hand or using other rules to concatenate the various parts)
And you also have to parse through the returned XML to get the results.
But technically it can be done with just that small amount of java code – and its entirely generic you can call any decision service using this mechanism.
If you want to try it you will have to read the Corticon docs that cover creation of extended operators.
You might also be able to make this a bit simpler by using the REST interface.