how to enable field edit - only once

[Efrat Noam]

I'm looking for a way to freeze a field value after the first time its being populated, and this way to preserve it's original value 

[Niranjan]

Hi @Efrat Noam ,

Remove the field from edit screen and have it only on create and view screen. 

[Joe Pitt]

@Niranjan That will only work if the reporter is supposed to fill out the field. If the field is supposed to be filled out further down the workflow it can be put on a transition screen and the view screen provided that transition field is never shown again, even if the issue is reopened. That part may be tricky.

[Efrat Noam]

Thanks, it's actually even trickier...

I have a field in which we hold our expected version number for release candidates. I would like to know when we are moving candidates from one version to another, repeatedly. My Idea was to copy (via automation) the value from this field - to other custom field, that will be locked. So I need somehow to define an automation rule that will only run once - The trigger should be when the version value is updated for the first time. It can be either while creating the ticket or while editing it (even w/o transition)

[Niranjan]

Agreed @Joe Pitt .

@Efrat Noam - Let us consider CF1 and CF2.

You can place the field CF1 on the transition screen and view screen. You can then use a conditional postfunction (with plugin like JSU or script runner) to copy from CF1 to CF2 . The condition can be "copy the field value CF2 only if CF2 is empty)" so that CF2 can be set only once. I have not tried this idea, but I believe it would work. 

CF1 - original field

CF2 - Field that will hold CF1 value

Regards

Niran

[Efrat Noam]

I've managed to resolve it - if you are interested:

the destination field is "read only" and automation trigger will run only if it is empty (= once).

thanks!