DDD

What is domain logic?

When working on a project, you can point out two distinct areas: problem space and solution space.

프로젝트를 진행할때 문제영역과 해결영역으로 나눌수있다.
problem space : 소프트웨어가 해결해야할 실제 문제
solution space : 문제 영역에 대한 솔루션

To do that, you need to look at whether or not the code makes decisions that have a business meaning. That is what differentiates domain logic. Your domain model is responsible for generating business-critical decisions while all other parts of your code base just interpret those decisions or provide input needed to make them.

비즈니스 의미를 가지는 로직은 도메인로직으로 볼수있다.

None of the two code samples make the decision by themselves, they both delegate it to the domain model. That’s essentially how a proper separation of concerns often looks like. While the application services layer can contain quite a lot of code, none of it should be about making any business-critical decisions. The only place for taking them is the domain model.

비즈니스 의사결정은 오직 도메인로직에 있어야 한다.

Summary

Domain logic (aka business logic, business rules, and domain knowledge)

All other types of logic orchestrate the decisions made by the domain model and transform them into side-effects: save them to the data store, show to the user, or pass to 3rd-party services.

도메인외 다른로직들은 도메인이 결정내린 사항을 저장하거나 전송하거나 다른 서비스로 요청을 보내는 것

It’s important to separate domain logic from other types of logic as it helps keep the overall code base simpler.

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Domain-Driven Design – What is it and how do you use it?

Factories: As we’ve discussed through a number of design patterns articles already, DDD suggests the use of a factory, which encapsulates the logic of creating complex objects and aggregates, ensuring that the client has no knowledge of the inner-workings of object manipulation.

factory 패턴으로 DDD root를 만들어 낸다는거 같은데 어떤케이스에서 쓰느거지... 예제가 필요해..

Domain Event: An object that is used to record a discrete event related to model activity within the system. While all events within the system could be tracked, a domain event is only created for event types which the domain experts care about.

모델상태변화에 따른 시스템에 발생시키는 이벤트 같은데 아직 잘..

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DDD Factories use case
DDD Domain Event use case