script help to add user to watch list

[taddparris]

I have a script which is working currently to add the user in the assigned_to field on a Change Task to the watch list on the parent Change Request.   This script does not duplicate entries, and successfully adds the user when it changes.   The one thing missing which I cannot figure out, if the user in the assigned_to field changes, how to remove the existing user from the watch list.   Example if Employee A is assigned a CTASK, and then switches to Employee B, both will appear on the watch list.   I only want the current user "Employee B" assigned.

Thinking I may need to go a different route and use a glide record?

function onBefore(current, previous)
{   
var RFC = current.change_request.getRefRecord(); 
var wlArr = RFC.watch_list.toString().split(','); 
var user = current.assigned_to.toString();
var arrUtil = new ArrayUtil();       
if (!arrUtil.contains(wlArr, user))
       wlArr.push(user);
RFC.watch_list = wlArr.join(','); 
RFC.update();   
}

Any help would be much appreciated.

[Chuck Tomasi]

Hi Tadd,

I have a script include that can help with that. You can use methods to check if someone is in the list, add them, remove them, get the entire list, etc. It was specifically made around the watch list, but works with any other list field.

Managing Glide Lists

[taddparris]

Would I just add your script in the link to a Business Rule, or just parts of it?   Would it require customization on certain lines to match tables and such?

[Chuck Tomasi]

Hi Tadd,

The idea is that the script in my article goes in a new Script Include. These can be thought of as libraries of reusable code that are called as needed. Once in place, you can call it from your business rule (or any other server side script) something like this (untested)

var lu = new ListUtil(current.watch_list);

// If the current assigned to person is not in the list, add them

if (!lu.isInList(current.assigned_to))

        lu.addToList(current.assigned_to);

// If the assigned to field changed, check if the old person was in the list and remove them

if (current.assignedTo.changes()) {

        if (lu.isInList(previous.assigned_to))

                  lu.removeFromList(previous.assigned_to))

These may help with script includes.

Script Includes - ServiceNow Wiki

TechNow Episode 6 | Script Includes - YouTube