Validators are used to guarantee accuracy of existing issue data or data entered on a transition screen before a transition is performed.
JWT for Jira Cloud currently offers a single, but yet very powerful validator to let you control under what circumstances users can execute a transition - the Jira expression validator.
As the name states, the validator uses the built-in Cloud functionality of Jira expressions - a unique feature of Jira Cloud which is developed by Atlassian.
Use cases and examples
|Use case||Function||Use case description||Complexity|
|Block a transition based on issue links|
Evaluate issue links and hide transitions based on the outcome.
|Block a transition based on sprint information|
Make sure that an issue is not in an active sprint.
|Check current issue status|
Check whether the current issue is in a particular status.
|Check for unresolved sub-tasks|
Check whether the current issue has any unresolved sub-tasks.
This is particularly important if you want to block a parent issue as long as work is still being done on related sub-tasks.
|Check parent issue type|
Check whether the parent of the current issue is of a certain issue type.
This is particularly important if you want to reuse a workflow for multiple sub-task issue types but only want a transition to be available if the sub-task belongs to a certain user story or a bug.
|Make a field required|
Make individual fields required or make sure that they have an existing value.