GlideAjax: call the server from a client script

When a form needs data the browser doesn’t have, use GlideAjax. It keeps logic and security on the server, and the asynchronous call keeps the form responsive.

// 1. Script Include "UserInfoAjax", with "Client callable" checked
var UserInfoAjax = Class.create();
UserInfoAjax.prototype = Object.extendsObject(AbstractAjaxProcessor, {
  getManagerName: function () {
    var userId = this.getParameter('sysparm_user');
    var user = new GlideRecord('sys_user');
    if (!userId || !user.get(userId)) return '';
    return user.getDisplayValue('manager');
  },
  type: 'UserInfoAjax',
});

// 2. onChange client script on the caller field
function onChange(control, oldValue, newValue, isLoading) {
  if (isLoading || !newValue) return;
  var ga = new GlideAjax('UserInfoAjax');
  ga.addParam('sysparm_name', 'getManagerName');
  ga.addParam('sysparm_user', newValue);
  ga.getXMLAnswer(function (managerName) {
    g_form.addInfoMessage(managerName ? 'Manager: ' + managerName : 'No manager on record');
  });
}

How it works

• sysparm_name selects the Script Include method; other sysparm_ parameters carry your inputs.
• getXMLAnswer() is asynchronous and hands the return value straight to the callback.

Gotchas

• Avoid getXMLWait(): it freezes the browser and isn’t available in Service Portal.
• Client-callable methods can be invoked by any logged-in user. Check permissions inside the method if the data is sensitive.