Copy of Greeting Service

This sample demonstrates a simple greeting service which uses business rules.

Note

Before executing this sample, it is recommended that you refer to section Exposing Rules as Services which explains in detail the process of writing and deploying a business rule.

Sample Rule Definition

Rules

Rule 1 : If the time is between 12 and 18, say good afternoon.

Rule 2 : If the time is between 6 and 12, say good morning.

Rule 3 : If the time is between 18 and 24, say good night.

Facts

There is one fact, which is "A user logged-in into the system". Also, "GreetingMessage" is used to present the result of the rule execution.

package samples.greeting;
import java.util.Calendar;

/**
 * User
 */
public class User {
    private String name ;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int now(){
        Calendar cal = Calendar.getInstance();
        return cal.get(Calendar.HOUR_OF_DAY);
    }
}
    
package samples.greeting;
/**
 * greeting message
 */
public class GreetingMessage {
    private String message ;
    public String getMessage() {
        return message;
    }
    public void setMessage(String message) {
        this.message = message;
    }
}

Rule Service Configuration (service.rsl)

An in-line rule set is used within the service.rsl file as follows.

<ruleService
       name="GreetingService"
       xmlns="http://wso2.org/carbon/rules"
       targetNamespace="http://com.test/greeting">
    <ruleSet>
       <rule resourceType="regular" sourceType="inline">
           <![CDATA[
               package greeting

               import samples.greeting.GreetingMessage;
               import samples.greeting.User;

               rule "Is Morning" no-loop true
               when
                   user : User()
                   eval((6 < user.now()) && (user.now()< 12))
               then
                   GreetingMessage msg = new GreetingMessage();
                   msg.setMessage("Good Morning  " + user.getName() + " !!! ");
                   insertLogical(msg);
               end

               rule "Is afternoon" no-loop true
               when
                   user : User()
                   eval((12 <= user.now()) && (user.now() < 18))
               then
                   GreetingMessage msg = new GreetingMessage();
                   msg.setMessage("Good Afternoon  " + user.getName() + " !!! ");
                   insertLogical(msg);
               end

               rule "Is Night" no-loop true
               when
                   user : User()
                   eval( (18 <= user.now()) && (user.now() < 24))
               then
                   GreetingMessage msg = new GreetingMessage();
                   msg.setMessage("Good Night  " + user.getName() + " !!! ");
                   insertLogical(msg);
               end
           ]]>
       </rule>
    </ruleSet>
    <operation name="greetMe">
       <input wrapperElementName="user" namespace="http://com.test/greeting">
           <fact elementName="user" namespace="http://com.test/greeting" type="samples.greeting.User"></fact>
       </input>
       <output wrapperElementName="greetingMessage" namespace="http://com.test/greeting">
           <fact elementName="greetingMessage" namespace="http://com.test/greeting" type="samples.greeting.GreetingMessage"></fact>
       </output>
    </operation>
</ruleService>

Deploying and Testing the Service

1. Deploy the rule service through the BRS management console. You can follow either of the two methods:

Bundle all artifacts in an .aar file and upload it (Rule Service -> Upload menu).
Create using the Rule Service wizard UI (Rule Service -> Create menu).

The above steps are discussed in detail in section Exposing Rules as Services.

2. After deployment, the service will appear in the "Deployed Services" window of the BRS management console. Access the service's dashboard by clicking on it.

3. In the "Client Operations" widget of the dashboard, invoke the Try-it tool to test the service.

4. In the service's TryIt window, issue a request similar to the following.

<name>your name</name>

5. Alternatively, you can use code generation link in the "Client Operations" widget of the dashboard to invoke the service. A client using generated stub codes is shown below where the codes were generated with option "Unpacks the databinding classes".

package org.wso2.carbon.samples;

import java.lang.String;
import org.wso2.carbon.samples.greetingService.greeting.*;
import org.apache.axis2.AxisFault;
import java.rmi.RemoteException;

public class GreetingServiceTestCase {

    public static void main(String[] args) {

        try {
            GreetingServiceStub greetingServiceStub = new GreetingServiceStub("http://localhost:9763/services/GreetingService");

            UserE userRequest = new UserE();
            User user = new User();
            user.setName("your name");
            User[] users = new User[1];
            users[0] = user;
            userRequest.setUser(users);

            GreetingMessage[] greetingMessages = greetingServiceStub.greetMe(users);
            String result = greetingMessages[0].getMessage();
            System.out.println(result);

        } catch (AxisFault axisFault) {
            axisFault.printStackTrace();
        } catch (RemoteException e) {
            e.printStackTrace();
        }
    }
}