In Xpages. How can I pass values from a serviceBean (called by extlib REST service) back to a notes document

Question

In Xpages (9.0.1FP9). I’m am receiving a webhook from a payment gateway (Braintree) using the extlib. REST service / serviceBean. I get the package from the webhook and I can parse the information. But I can’t get a handle on the Domino Session inside the JAVA so I can create or update a Notes document.
My JAVA skills a limited so I'm stuck. Any help would be appreciated.

Xpage
{
    <xe:restService id="JSONSearch" pathInfo="test1" state="false">
        <xe:this.service>
            <xe:customRestService contentType="application/json"
                serviceBean="com.mydomain.bt_Webhook1">
            </xe:customRestService>
        </xe:this.service>
    </xe:restService>
}

package com.mydomain;

import java.io.IOException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.ibm.domino.services.ServiceException;
import com.ibm.domino.services.rest.RestServiceEngine;
import com.ibm.xsp.extlib.component.rest.CustomService;
import com.ibm.xsp.extlib.component.rest.CustomServiceBean;
import com.braintreegateway.*;
import lotus.domino.*;

public class bt_Webhook1 extends CustomServiceBean{

//=====================================================================
    String btMerchantID = "abcdefgh1i2jk3lm";
    String btPrivateKey = "abcdefghijkl2mnopq3rstuv4wxyz";
    String btPublicKey = "zyxwvutsr1qpo2nm";    

    BraintreeGateway gateway = new BraintreeGateway(
        Environment.SANDBOX,            //Environment.SANDBOX or Environment.PRODUCTION 
        btMerchantID,                   //Merchant ID
        btPublicKey,                    //Public Key
        btPrivateKey                    //Private Key
    );
    //===================================================================== 
    @Override


    //wissel.net; http://dominoherald.blogspot.com/2016/02/rest-via-service-bean.html
    public void renderService(CustomService service, RestServiceEngine engine) throws ServiceException {
        HttpServletRequest request = engine.getHttpRequest();
        HttpServletResponse response = engine.getHttpResponse();

        response.setHeader("Content-Type", "application/json; charset=UTF-8");
        response.setStatus(200);

        try {
            String btsignature = request.getParameter("bt_signature");
            String btpayload = request.getParameter("bt_payload");

            WebhookNotification webhookNotification = gateway.webhookNotification().parse(
                btsignature,
                btpayload
            );

            String tKind = webhookNotification.getKind().toString();            
            String tTimeStamp = webhookNotification.getTimestamp().getTime().toString();
            String tMerchantAcctID = webhookNotification.getMerchantAccount().getId();

            System.out.println("------------------------------------------------");
            System.out.println("tMerchantAcctID: " + tMerchantAcctID);
            System.out.println("tKind: " + tKind);
            System.out.println("tTimeStamp: " + tTimeStamp);
            System.out.println("------------------------------------------------");

/*
            //There is no way to create a new Domino Session in a Java Code element.  
            //The current Domino Session object must be passed as a parameter to the method via the global session object. (TLCC Java courseware)

            Session session = getCurrentSession(); // -- ERROR The method getCurrentSession() is undefined for the type bt_Webhook1
            Database db = session.getCurrentDatabase();
            Document doc = db.createDocument();
            doc.replaceItemValue("Form", "Webhook");
            doc.replaceItemValue("webhook_Timestamp", "Timestamp");
            doc.replaceItemValue("webhook_Kind", "Kind");
            doc.replaceItemValue("webhook_MerchantAccountID", "MerchantAccountID");
            doc.save();

            doc.recycle();
            db.recycle();
*/

            response.getWriter().close();
            System.out.println("done");   
            return;
        } catch (IOException e) {
            // TODO Auto-generated catch block
            System.out.println(e.toString());
            return;
        }
    }   
}

Answer 1

You may be able to get it by resolving the session object from the XPages runtime, e.g. Session s = (Session) ExtLibUtil.resolveVariable("session");

This is extended from Eric McCormick's code in his blog post https://edm00se.io/xpages-servlets/servlets-handling-data-round-house-kick/. ExtLibUtil gives shortcuts over his use of FacesContext.