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At this point in time, the list of system variables include:
Date and Time
$today - today’s date and time
$tomorrow - tomorrow’s date and time
$time - current time
$datetime - current date
$nextWeek
Current User
$username - the user that applying the hierarchy
$userEmail - email of the user that applying the hierarchy
Current Issue Details
$projectKey - the key of the project where the issue will create
$projectName - the name of the project where the issue will create
$projectLeadName - the leader of the project where the issue will create
$issueKey - the key issue that will create
Parent Issue Details
$parentKey - the key of the parent issue
$parentSummary - the summary of the parent issue
$parentDescription - the key of the parent issue
$parentIssueType - the issue typo of parent issue
$parentStatus - the status of the parent issue
$parentPriority - the priority of the parent issue
$parentDueDate - the due date of the parent issue
As it was already mentioned before, variables - are placeholders that are automatically filled with data that is available at the moment of the Issue creation.
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