How to handle transactions using Spring JPA data?

Question

I'm going to start creating a new application and would like some feedback on the approach I plan to use. We will use the spring and spring jpa data.

• Can controllers call domain and repository services, or should the controller only make calls for applications and infrastructure services?

• If it is “normal” to call the domain services and repositories from the controller and the domain service operation, a transaction is required, can I / just put the @Transactional annotation in the domain service method? Or should I have an application service that ends the call (not sure if I like this approach because you will have a bunch of passes through methods)?

• If it is not “normal” to call domain services and repositories from the controller, do I need to create application services to wrap all possible calls to the domain service (as I said in 2, that there can be many ways to go through)?

The best solution I can come up with is something like the following:

• Repositories will have an @Transactional annotation with the distribution REQUIRED when writing to the database and the distribution set for readOnly = true and the distribution set for SUPPORTS when reading from the database.

• Domain applications and services will add @Transactional annotation as needed

If the dispatcher ever needs to make a direct call to the repository of a domain service or application service, he can. No passes.

Answer 1

I do not understand your question. What do domain services do? I knew Application Services and Domain Repositories very well.

Spring has two levels of service and data access. The service level can be used by @Service (there will be Services applications in your design), but the @Transactional tag is not used.

The data access level uses the @Repository tag, as well as the @Transactional tag, because this level is directly connected to and works with the database. So, I like to know which domain service function. I dont understand what.

Thank you friend.

Answer 2

I personally would get access to your domain services and applications from your controllers. Thus, you should only put @Transactional annotations at the same level. You get the transaction out of the box at your repository level if you extend the regular Spring repository interfaces. I would leave this layer as simple as possible. Put your readOnly and other service level configuration.

Creating “pass” methods allows you more flexibility in the future if you ever decide to change your DAO implementation.