How can I add a workflow transition condition to make sure a role has a user assigned, which add on or plugin is required for this?

Raj Vardhan

How can I add a workflow transition condition to make sure a role has a user assigned, which add on or plugin is required for this? 

I need to make Assignee field mandatory but in condition I am not having any option to make the user mandatory. So please tell how to get such option in this.

Nic Brough -Adaptavist-

Those both sound more like validators than conditions, but you can do them both.

Off the shelf, "make sure a role has a user assigned" is easy - you can just use "user is in role x".  That guarantees that role X has at least one user in it.

Making assignee mandatory is definitely better done as a validator (and there's one in the JSU add-on, if not the core, for requiring system fields).  As a condition, I think you'll need to find/write something, as most people do it as a validator.