Application & domain

services

Problem

• Service can call other service

• There is mess with DB transaction control

Problem

Solution

• Introduce layers

• Control DB transaction in one place

Application service

• Called only by handler (gRPC, HTTP, Kafka, CLI)

• Controls DB transaction

• Calls business logic (domain services, model's methods)

Domain service

• Called only by handler or application service

• Knows nothing about DB transactions

• Calls model's methods or other domain services

Solution

Business operation with DB tx

Business operation without DB tx

Read more

https://vaadin.com/blog/ddd-part-3-domain-driven-design-and-the-hexagonal-architecture