Why does my script include return "empty"?

[JCavin]

Here's the situation: I get an XML object back. The problem is that it only ever has the elements and attributes that were added during the request. I can't get an answer/value back from the server.

I have a UI Action calling a Script Include. The Script Include is in the Global app and the client-side UI Script is in Audit.

Here's how the Script Include is setup:

Here's the Script Include code:

var prettydiffSN = Class.create();
prettydiffSN.prototype = Object.extendsObject(AbstractAjaxProcessor, {
	initialize: function (){
		var result = this.newItem("result");
		result.setAttribute("message", "The great payload");
	},
    type: 'prettydiffSN'
});

Here's the client-side code (in a UI Action, with the Client box checked):

function runPrettyDiffPrev() {
	jslog('prev Version ui action');
	
	var ajax = new GlideAjax('global.prettydiffSN');
	ajax.addParam('sysparm_name', "initialize");
	ajax.getXML(getDiffCode);
	
}


function getDiffCode(response) {
	var doc = response.responseXML.getElementsByTagName("result");
	var message = doc[0].getAttribute("message");
	jslog(message);
	
}

Here's the result:

<?xml version="1.0" encoding="UTF-8"?><xml sysparm_max="15" sysparm_name="initialize" sysparm_processor="global.prettydiffSN"/>

Actually, this version throws an error "Cannot read property 'getAttribute' of undefined". But, I can't find where it deviates from the documentation:

https://docs.servicenow.com/bundle/kingston-application-development/page/script/ajax/topic/p_AJAX.ht...

[Rogers Cadenhe1]

When you want to call a script include function asynchronously from a client script or other client-side code, the function needs to return a value:

initialize: function() {
  var result = this.newItem("result");
  result.setAttribute("message", "The great payload");
  return result;
},

In the client code the value returned can be retrieved by calling the responseXml.documentElement.getAttribute("answer") method:

var ajax = new GlideAjax('global.prettydiffSN');
ajax.addParam('sysparm_name', "initialize");
ajax.getXML(getDiffCode);

function getDiffCode(response) {
 var doc = response.responseXML.documentElement.getAttribute("answer");
}

[JCavin]

It turns out, your approach is the simplest (most proper?) way to do this. However, I was shadowing the "initialize" function. After I fixed that, the tag/attribute, "result"/"message", were present along with the returned value you suggested.

[Akshat Rastogi · Accepted solution]

Hi,

Instead of calling initialize function call say XYZ, for example:

Script include:

var prettydiffSN = Class.create();
prettydiffSN.prototype = Object.extendsObject(AbstractAjaxProcessor, {
    XYZ: function (){
        var result = this.newItem("result");
        result.setAttribute("message", "The great payload");
    },
    type: 'prettydiffSN'
});

Client script:

function onLoad() {

    var ajax = new GlideAjax('global.prettydiffSN');
    ajax.addParam('sysparm_name', "XYZ");
    ajax.getXML(getDiffCode);
    

function getDiffCode(response) {
    var doc = response.responseXML.getElementsByTagName("result");
    var message = doc[0].getAttribute("message");
    jslog(message);
    alert(message);
    
}
}