Updating a List field with a Business Rule each time another field changes

[Wayne Richmond]

Hi there. I have the following requirement: On the cmdb_ci_computer table I have added a new List field called u_users which references the sys_user table. When assigned_to (also references sys_user) changes I want to copy the value to the u_users field, however, I don't want to replace the existing value but rather add to it. What I'll eventually have is a list of users who have been recorded to have used a computer. I also don't want duplicates adding but I figure SN might sort this for me automatically. Any thoughts? This is my current effort:

When: before (Insert and Update)

Condition: [Assigned to] [changes]

(function executeRule(current, previous /*null when async*/) {
current.u_users = current.assigned_to;
})(current, previous);

Thanks

[Justin Abbott · Accepted solution]

UPDATED to filter out duplicates.

I would capture what's already in the field, then add the new person.

Something like this...

(function executeRule(current, previous /*null when async*/) { 
   var users = current.u_users.split(',');

   users.push(current.assigned_to.toString());

   users = new ArrayUtil().unique(users);

   current.u_users = users.toString();

})(current, previous);

[Wayne Richmond]

Hey, thanks for the reply! That worked a treat, except, it did create duplicates:

Any idea how I could prevent this?

[Justin Abbott]

When I tried it out in my instance, it worked just fine without duplicates.

Can you paste the code you tried? The use of '.toString()' was incredibly important here.

[Wayne Richmond]

Thanks! I missed your update before I tried the code. Having added the updated code it works perfectly! Thank you so much, that's really really helpful. All the best my friend.