2017-12-15 December learning session

Date

15 Dec 2017

Attendees

• Sebastian Brudziński

• Nikodem Graczewski (Unlicensed)

• Mateusz Kwiatkowski
• Łukasz Lewczyński (Deactivated)
• Paweł Albecki (Deactivated)

Goals

• Watch learning material Domain-Driven Design in Practice
   (https://www.pluralsight.com/courses/domain-driven-design-in-practice) - Extending the Bounded Context with Aggregates, Introducing the Second Bounded Context
• Discuss watched materials and compare to how things are handled in OpenLMIS - are there any ideas/approaches/workflows we can adopt in OpenLMIS?

Discussion

• Aggregates:
  • Requisition - root entity
    • line item - entity
      • Line items should not be available outside of Aggregate.
      • Getter should return immutable list of immutable objects or no getter, line items should be updatable through Requisition Aggregate.
      • Setter should be removed.
      • Line item should not have id in DTO.
    • Value Objects - worth having (discussion already on Dev Group)
  • Order
    • POD has Order, Order has line item, POD line item has order line item.
    • Order line item should not be referenced from outer context.
  • Proof of Delivery
    • for every line item values of quantity shipped, quantity received, quantity returned, replaced product code.
    • How to get order line item details on ui? e.g. by orderable code.
• Bounded Context - follow up from previous learning meeting discussion, solution space
• Sub-domains - problem space

Wrap up

We have asked every participant to give a score on how useful this meeting was and how helpful this specific material was. The voting was anonymous and each participant could give a score from 1 (useless) to 10 (very useful).
The averages were:

How useful are those meetings:  8/10
How useful was this specific material?

• Extending the Bounded Context with Aggregates:  8.2/10
• Introducing the Second Bounded Context:  6.8/10
  

Final thoughts

• It's worth to consider using AggregateRoot, ValueObject superclass/interface.
• Getters should return immutable list of immutable objects or should be not implemented.

Action items

• Mateusz Kwiatkowski to start discussion about separate resource for requisition for approval.
• Łukasz Lewczyński (Deactivated) to create ticket for order line item should not be referenced from outer context (POD). →  OLMIS-3827 - Getting issue details... STATUS
• Paweł Albecki (Deactivated) to follow up with requisition line items should not be available outside of Requisition Aggregate.