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  1. OMG Issue

CR — Sentry behavior for OnParts referring to Repeating PlanItems is unclear

  • Key: CR-11
  • Legacy Issue Number: 19481
  • Status: closed  
  • Source: ( Thijs Petter)
  • Summary:

    Suppose we have a plan item A that has an entry criterion and the onPart refers to a Complete transition of a plan item B that is repeatable.
    This referenced plan item B obviously has it's own lifecycle.

    The plan item A remains Available until the entry criterion is satisfied.

    But when is the entry criterion satisfied if multiple instances of B get added to the plan? Is it upon the first plan item A that is completed, or should all instance of A be completed?

    This is especially intriguing if the referenced planitem is a milestone.
    Evaluation of the RepetitionRule is clear, it should happen on create. Repeating the plan item is clear for Task and Stage, see 7.6.4: Whenever a Task or Stage becomes Active, a new instance of the plan item is added to the plan in state Available, triggering same cycle of evaluation of the repetition rule and potentially adding a new plan item if the plan item becomes Active.
    However, for Milestones this behavior of adding the repeated plan item is not specified in 7.6.4. But it seems rather intuitive to do this when the milestone Occurs.
    However, now comes the problem with sentries listening to this repeating milestone: when the sentry listens to the "Occur" of the milestone, then the entry criterion get's satisfied, and the listening plan item can go to Active ... However, at the time of the Occur transition of the milestone to Complete, a new plan item for the milestone is added to the plan, making immediately the transition Create (to have it go from Null to Available state) ... the listening sentry now immediately gets dissatisfied because of the new plan item's transition ...

    I guess this is a place to reconsider or make more explicit what the intended execution semantics should be.

  • Reported: CMMN 1.0 — Tue, 17 Jun 2014 04:00 GMT
  • Disposition: Resolved — CMMN 1.1
  • Disposition Summary:

    Clarify sentry behaviour under repetition rule

    The question in here is what happens (what is the execution semantics) when a sentry is waiting in a plan item that has a repetition rule true.
    This clarification should be added in page 79, section 7.6.4 RepetitionRule

  • Updated: Tue, 29 Mar 2016 15:06 GMT
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