Notifying Workflow Initiatior

[cancan101]

I am looking to notify the workflow initiator (ie the user that created the Object) on one of the transition steps.

Is there anyway to either:

• Notify based on the concept of "object creator" (owner?)
• Create an expression that matches the object creator (owner?), ideally using the username and not the userId

From the docs:

A symfony expression can be configured here. All sets of notification which are matching the condition will be used.
condition: "" # optional some condition that should apply for this notification setting to be executed

Something like: subject.getOwner().getUsername() == 'Joe'.

or if I added a field to the object, is there anyway to use a symfony expression for notifyUsers to notify based on the value of that field?