How do you restrict users from changing the Priority of a ticket?

Question

Created a Behaviour :

* Use Validator Plugin     = Enabled
* Guide Workflow           = Helpdesk Workflow
* Fields: Priority             Optional, Read Only, Shown
* Conditions:                  Except  Project role (HelpDesk)

The Priority apparently is only restricted when creating the issue, it can still be changed in View and Edit. What am I missing.

Thank you for any help you can offer

Marcel Vlems · Answer

I have the same problem where I want to set permissions to the Priority-field but cannot find the Behaviour-app for Jira Software. Anyone knows what happened with it or if there's another solution?

Nadine Titus · Answer

Thank you for your reply Harry Ha. I am using the Behaviours Plugin as I indicated above, and the Priority field is restricted when the issue is being Created, so that works. But once you submit the ticket, it can still be modified. I am looking for a fix with the Behaviours Plugin. Wondering if this is a bug. 
Can you walk me thru the doing this in the Behaviours Plugin or can you give me an example code?

HarryH · Answer

You can set the priority as readonly and make it readable to certain users, https://jamieechlin.atlassian.net/wiki/display/JBHV/JIRA+Behaviours+Plugin

The second solution is, you can add workflow to change the priority, and add validator to limit the user who is changing the propriety.