[Question] How best to break up large use cases?

[ydennisy]

Hi @stemmlerjs !

I was wondering if you have any insight into how best to break up large use-cases?

I have some constructors which now look like the following:

  private usersRepo: UsersRepo;
  private dealsRepo: DealsRepo;
  private brandsRepo: BrandsRepo;
  private audiencesRepo: AudiencesRepo;
  private googleService: GoogleService;
  private brandService: BrandService;

Is this where the concept of a service would come in and we would have a relationship such as controller -> use-case -> services[brand, user, ...]

Thanks in advance!

[gbrennon]

Hey buddy! How are u doing?

One thing that can guide u is reason about the "NAME" of that UseCase! This is a good reference to reason about that abstraction purpose.

What u can do to solve this:

• remember: an application service should ORCHESTRATE lower-level operations
• distribute the business logic between domain services, entities and value objects
• think about why u are bearing those dependencies

i would suggest u applying domain events to decouple computations! imagine that we define some usecase named AcceptUserDeal. This usecase would be responsible for persisting user and deal modifications in the database and AT THE END OF THE TRANSACTION u could be publishing a UserDealAccepted domain event!

this domain event would be handled by other usecase, for example, PublishDealDetails and then this one would relate to creating a google+ post or whatever u want to do.