Create notifications to group or individuals based on state transition

[jbdfw]

I've looked around, and seen a variety of tickets about notifications, but nothing exactly like this:

I would like to have the ability to create a notification to a group or person(s) for a particular state transition. For instance, when we go to a ready for test state, would like to be able to fire an email to the QA lead(s) letting them know something is new in their queue. Would be even nicer if some text could be specified, so that a notification to QA when something is ready for testing would be different than a notification to the build engineer when something is ready for build (just an example).

[rblank]

This should be done in a plugin implementing the ITicketActionController interface. Alternatively, you might be able to achieve the same effect using ​th:AdvancedTicketWorkflowPlugin and the run_external action.

[cboos]

We should nevertheless think about making it easy for plugins to send mails, when reworking the notification system.

It's fairly common in worklfow in other systems to trigger e-mails upon state transition. For example #6613 could be dealt with a finer-grained configuration of the notification in relation with the workflow (and there might be others).