I think there is no “better way” for converting your domain objects to your DTO objects, it’s a matter of taste. In my projects I convert the domain objects to the DTO in the service layer as part of my “business logic”. So you reduce the accessability of your domain objects only to your service … Read more
Ok I’ve changed my mind. I have been trying to deal with VOs a bunch lately and after watching this http://www.infoq.com/presentations/Value-Objects-Dan-Bergh-Johnsson it clarified a couple of things for me. Commands and Event are messages (and not objects, objects are data + behavior), in some respects much like DTOs, they communicate data about an event and … Read more
Short answer: No. Long answer: repository is responsible for turning persisted data back to entities (models) and vice versa. Model is a business Model representing a business entity. DTO on the other hand – while looks like Model – is concerned with transfer of the object between various environment and in essence is a transient … Read more
Recommendation is that you should just have one DTO class for each entity suffixed with DTO e.g. CustomerEntryDTO for the Customer entity (but you can certainly use inheritance hierarchies as per choice and requirements). Moreover, Add a abstract DTOBase kind of base class or an interface; and do not use such deep inheritance heirarchies for … Read more
It really depends on the complexity of your application. Mixing domain objects into the view layer has two possible implications: You’ll be tempted to modify your domain object to accommodate things you need in the view layer Your View layer will contain extra complexity caused by a mismatch between what your domain objects offer and … Read more
Separate, simple DTOs will make your life infinitely easier. It will require more code, but it will be boring, simple code, that is easily tested, and allows your interfaces to change and evolve independently. Make a DTO for each request endpoint and a separate DTO for each response. Otherwise, you will eventually be sad. If … Read more
Define the DTO to the layer where the source of the values comes from. Relative to OP’s question: place the DTO in the Application Service Layer. DTO is an output of that layer, it makes sense if you define it there. Don’t put your DTO in the Domain Layer. The Domain Layer does not care … Read more
Short answer: Entities may be part of a business domain. Thus, they can implement behavior and be applied to different use cases within the domain. DTOs are used only to transfer data from one process or context to another. As such, they are without behavior – except for very basic and usually standardised storage and … Read more
A benefit of having a mapper that sits between your domain and your DTO is not as appearent when you are only supporting a single mapping, but as the number of mappings increases, having that code isolated from the domain helps keep the domain simpler and leaner. You won’t be cluttering your domain with a … Read more
Domain and model objects are essentially the same, and may contain business logic. Depending on implementation, domain and DTO objects may be equivalent if you remove business logic from the model into a service class. Often a key variant of the DTO is the View Model, which is used purely to transfer data between the … Read more