Embedded Nature

🧠 Take ownership of your learning journey. Identify areas of interest and expertise, and actively seek resources, books, courses, mentors, and my newsletter 🗞️ to expand your knowledge and skills.

To learn more, click the link in my bio. 👆🏾

COMMAND QUERY RESPONSIBILITY SEGREGATION

“Every method should either be a command that performs an action, or a query that returns data to the caller, but not both.”

CQRS
You should have a strict separation between the Write Model and the Read Model. Those two models should be processed by separate objects and not be conceptually linked together.
‣ Think of CQRS as cutting your model and API into vertical slices, which you should.

Each command/query handler is a separate silo.

Commands
Commands are interactions that perform changes to the service. E.g. update the address of this customer or add a new orderline to an order.
‣ Both HTTP and messaging can be used to accept commands

Queries
Queries retrieve data without changing the state of the service. E.g. get the list of customer addresses or get all the details for this order.
‣ Queries are mostly implemented over HTTP.
‣ GraphQL or restQL will do

Gotta love data patterns 😁.

Follow the journey ⚡️🌱.