Tutorial 5: Deadlines#
The requirement: a request nobody decides on is not forgotten. While Approve waits, the managers are reminded.
A timer on the task#
Every 2 days is a timer boundary event on Approve:
- Cycle
R3/P2D: every 2 days (P2D), 3 times at most (R3), in ISO 8601. A Duration (P7D) fires once, after that long; a Date at that time. - Non-interrupting (the dashed circle): Approve goes on waiting, and the timer starts a path of its own, Remind the managers, which ends at Reminder sent. An interrupting timer would cancel Approve instead.
- When Approve is completed, its timer stops: nobody is reminded of a request already decided.
Timers are kept in the database: a server that restarts picks them up where they were.
Escalation#
To take a request away from managers who don't answer, add an interrupting timer to Approve, P7D, leading to a
task in the HR lane with the same form, and join it into the Outcome? gateway. Tutorial 7's tests show how to
test it without waiting a week.
Design choices#
- Every waiting task asks: what if nobody acts? A reminder, an escalation, or a deadline that decides by itself.
- Reminders don't interrupt; escalations do.
- Put the period in the model (
P2D), where it is documented and tested; or compute it from the data with an expression, when it varies.
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