Client script to populate choices variable select Box

[Rick27]

Hello, I created an include script making a GET API call and I would like to get the response and populate a select box variable from a service catalog, but I don't know exactly how to assemble this client script, it would be OnChange:

My script Include Ajax

var UpgradePreviewAjax = Class.create();
UpgradePreviewAjax.prototype = Object.extendsObject(AbstractAjaxProcessor, {
populateData: function() {
var patch_instance = this.getParameter('sysparm_patch_instance');
var url = patch_instance;
var request = new sn_ws.RESTMessageV2();
request.setEndpoint('https://' + patch_instance + '.service-now.com/api/now/table/upgrade_preview?sysparm_query=status%3Dcomplete&sysparm_fields=target_version%2Csource_version&sysparm_limit=');
request.setHttpMethod('GET');
var user = 'user';
var password = 'pass';
request.setBasicAuth(user, password);
request.setRequestHeader("Accept", "application/json");
request.setRequestBody(JSON.stringify(requestBody));
return request.execute();
},


type: 'UpgradePreviewAjax'
});

[Prateek kumar]

Check this out:

Solved: fetching data from rest API - ServiceNow Community

[Hitoshi Ozawa]

Something like below. Will add values of field "source_version" to selectbox named "SelectboxName".

function onChange(control, oldValue, newValue, isLoading, isTemplate) {
    if (isLoading || newValue === '') {
        return;
    }

    var ga = new GlideAjax('UpgradePreviewAjax');

    // Add parameters that you want to pass to the Script Include
    ga.addParam('sysparm_name', 'populateData');

    // Make the asynchronous call to the Script Include
    ga.getXMLAnswer(function(response) {
        // Process the response
        var answer = response.responseXML.documentElement.getAttribute('answer');
        var jsonData = JSON.parse(answer);

        // add to selectbox
        jsonData.forEach(function(item) {
            g_form.addOption('SelectboxName', item.source_version);
        });
    });
}