Invoking the Application Service / Use Case

In Domain-Driven Design, Application Services have a specific purpose.

The purpose of an Application Services is to get all the stuff needed in order for domain layer concerns to interact, than to save the result to persistence.

In the following example, using Interface Adapters (like IUserRepo), the responsibility is to:

  • Fetch the Aggregate(s) and any other objects needed in order to execute the domain logic.
  • Pass the objects to either an Aggregate's method OR a Domain Service.
  • Save the results of the transaction to persistence.

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