Decision Microservices with Spring Framework

OpenRules Release 7.0.1 provides a sampling and detailed tutorial of how to add an OpenRules-based service to the popular Spring framework. The new tutorial "Developing Decision Microservices with Spring Boot and OpenRules" in a step-by-step manner explains how to convert OpenRules-based decision projects into Decision Microservices and to deploy them on any server or a cloud environment supported by Spring. Read it and try to run the demo microservice "GreetingService" by downloading the new workspace called "openrules.spring" now included in the evaluation version.

Additional OpenRules API

Direct Access To Excel Data Tables from Java

In previous releases you needed to manually created an Excel table of the type Method to get an access to the Data table. For example, to get an access from Java to this Data table



you needed to create in Excel  special access method such this one:

 

Then in your Java launcher you needed to write

      Customer[] customers = (Customer[]) decision.execute("getCustomers");

The enhanced Decision's API includes the method "Object getData(String name)" that can directly access arrays described in the Excel's Data tables. So, you don't need anymore to create the Method "getCustomers" in Excel, and may simply write:

      Customer[] customers = (Customer[]) decision.getData("customers");

Similarly, if you have an Excel table of teh type Variable, e.g.



you may get a customer from this table by using the method "getVariable":

      Customer customer = (Customer) decision.getVariable("customer");

Spliting Decision into DecisionData and DecisionModel

You may use the new API "DecisionData" to separate an access to your Excel data from your decision model. For example, in the sample decision project "HelloJava" the Java class MainDecisionData gets an array of customers from the file "Test.xls":

     DecisionData data = new DecisionData("file:rules/Test.xls");
     Customer[] customers = (Customer[]) data.get("customers");
     or
     Customer customer = (Customer) data.get("customer");

Now instead of creating one decision based on the main Excel file, you may create an instance of the new class "DecisionModel" for the same Excel file. Then you may use this decision model to create multiple decisions that share the same rules repository. The same sample decision project "HelloJava" demonstrates this API:

      DecisionModel model = new DecisionModel("file:rules/Goals.xls");
      Decision decision = model.createDecision("DecisionHelloStatement");

When you create an instance of the DecisionModel, on the background an instanse of OpenRulesEngine is created as well: so it could be a relatively expensive operation. But the method "createDecision(String goal) is quick and highly efficent.

We modified some exemples in the workspace "openrules.models" to demonstrate the new API.

Download the latest complete OpenRules release 7.0.1 from here.

If you have any questions, comments or suggestions, please post them at the Google Discussion Group or send them directly to support@openrules.com.