Sprint Planner Helper – Session 8

Posted by Marcus Hammarberg on February 12, 2009
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This hour almost entirely was reading. I didn’t not feel comfortable yet with terms Repository and Service, or how they relate to each other.

Also I feel that I have looked to much at the architecture of ASP.NET MVC Storefront Starter Kit. I have incorporated stuff that I didn’t thought to much about – stupid, but I did it anyway.

But after a while I found this introduction to DDD and it explained some things for me. Here is how I understand the two fore-mentioned concepts:

  • A Repository are classes and methods that is used to load stuff from a data store. They are often written in a way that is easily mocked or replaced during testing.
  • A Service is used to hold a process or a flow through a business logic that does not fit well on a class in the domain model. They are stateless and take the entity that they operate on as parameter or loads the entities into memory via a repository.

Right now – in my solution there is a strange layering going on… The Controller is calling the Service that in turn calls the Repository. Although that could happen there really is no need for it since I am only getting stuff yet. If I later on need some functionality that doesn’t fit well into my domain model I will introduce a service for that.

Finally – so what I did was simply to remove the services and then TDD:ed (hey, that looks funky) a way to inject a repository into the Controller. It caused me to move things around a bit in the solution. But for the better. I learned that test-projects should only contain tests. TestData Repositories for examples are better placed in the Repositories-assembly.

I am really going back and forth – but at least I know what I am doing. And that’s the way you learn. Especially since I am on my own.



Published by Marcus Hammarberg on Last updated