Summary
Keychain introduces a new post-function to your system named Assign to Delegate of.
This post-function assigns the issue to a delegate user, according to its configured delegation source and delegations defined on the Delegation Configuration page.
The post-function assigns the issue only if there is a delegate defined for the configured delegation source. If there is no delegate user, the assignee of the issue is not changed.
Considering this behavior, you can configure the workflow with two consecutive assignment post-functions. First, assign the issue to the user responsible for the issue then assign it to the responsible's delegate. If no delegate is found, the issue will still be assigned to the responsible.
Delegation Sources
The condition function can be configured to get its Delegator from a number of sources.
The Current Issue referenced below is the issue that this condition is running on.
Assignee
If configured for Assignee, the field will take the assignee of the current issue as Delegator and will only allow the Delegates defined for that user to execute the transition.
Reporter
If configured for Reporter, the field will take the reporter of the current issue as Delegator and will only allow the Delegates defined for that user to execute the transition.
Project Lead
If configured for Project Lead, the field will take the project lead of the project (that the current issue is in) as Delegator and will only allow the Delegates defined for that user to execute the transition.
Single User
If configured for a Single User, the field will ask you to pick a user. Then it will use that user as Delegator and will only allow the Delegates defined for that user to execute the transition.
Project Role
If configured for a Project Role, the field will ask you to pick a project role. Then it will collect the users and user groups in the selected role (for the project that the current issue is in), use them as Delegators and will only allow the Delegates defined for those users to execute the transition.
User Group
If configured for a User Group, the field will ask you to pick a user group. Then it will use the selected user groups as Delegators and will only allow the Delegates defined for those users to execute the transition.
User Custom Field
If configured for a User Custom Field, the field will ask you to pick one of the Single User Picker or Multi-User Picker custom fields on your system. Then it will take the users in the selected user picker of the current issue as Delegators and will only allow the Delegates defined for those users to execute the transition.
If there are multiple delegates defined, the issue will be assigned to the first delegate with Assignable User permission on the issue.
If none of the delegates have Assignable User permission, the Assignee will not be changed.
Category
Category selection determines which delegation category the delegate will be based on.
If a specific category is selected, the issue will be assigned to the delegator's delegate in that category or (since the General category implicitly includes all other categories) General category.
If General is selected, the issue will be assigned to the delegator's delegate in the General category.