CQRS by Example

Query Side and the Read Models

As we’ve seen before, Hexagonal Architecture limitations have a lot to do with mixing Queries and Commands, and one of the biggest problems while trying to apply Domain-Driven Design is when the Domain Model gets spoiled with low-level presentation details. These details are mostly related to the Read side of the Data Model — such as a large number of reading methods, getters in Domain objects that break encapsulation, or bloating Aggregates in non-optimal ways for the sake of the presentation — and they make it difficult, if not impossible, to optimize Queries.

Once we split our application and extract our Queries into the Read Model, there won’t be a need for Domain intermediation or extra complexity while handling ...