In my understanding of your book, Application Services are just kind of a facade to translate requests to the domain model.
Domain Services were introduced to be a collaboration of Domain entities (Aggregate Roots): methods that do not really fit into a specific entity.

In term of projects (or layers), the Domain Services would be put in the Domain Model project? Or would they be put into a seperate project?

Application Services have their own project/layer as is visible from your book.


But I get confused about theese services/layers as they seem to have merged somewhere through your book. In the end it seems that the domain services (as I describe them here) are part of the application services. Not sure by heart, but they might have been private. I think I found this in the Agatha demo source code.


Could you please explain:
- the roles of each of these two services?
- where each of these services will be put (project/layer)?
- how they are different/the same/similar in some way?

I greatly appreciate your help and answers on this forum.

Hi Mr Fixxit,

Sorry for the late reply!

Take a look at this blog post on the differences between the domain and application services http://stochastyk.blogspot.com/2008/...en-design.html. I like to think of my application services as being the API into the code, a client interacts with the API (application services) and behind the scences and within the domain model a domain service may use multiple entities and value objects in collaboration to fulfill a business request.

I hope that answers your question, if not please respond and we can talk about the differences further.

Cheers
Scott