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by lgunsch 4518 days ago
I would stick with no classes being "fat". Breaking up fat classes into many smaller classes leads to code being really easy to understand, test, and develop. I tend to stick with the Single-Responsibility-Principle and classes do not become unmanageable. Some people argue that many small classes leads to complex code, but I have not found that to be true in any case I have come across.
2 comments
secstate 4518 days ago
Ah, but there be monsters in that sea too. I used to subscribe to the many-focused-models camp, but depending on the relationships you're trying to model, that can become damn-near unmaintainable as well.

I've actually begun building out more "wide" models, that is, models with a great many fields set to allow null/blank, because mixins and abstract base classes are very hard to maintain 3-4 years out. Don't misunderstand me, there's a place for those, but it's easy to get lost on road to abstraction.

Of course, the lesson is that if you're representing complex relationships in code, the implementation is going to wind up complex to some extent.

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ollysb 4518 days ago
There's another option besides mixins and base classes, composition. You can break your fat model into lots of smaller classes that you aggregate into your original model. The big advantage over using mixins is that the scope is kept much smaller. Keeping scopes small in general is always a good way to scale up to a large codebase (functional languages get this pretty much for free).
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lgunsch 4518 days ago
Yes, I generally stick to composition. "High level" classes end up using a bunch helper classes to perform specialized tasks. I find that I do not often find the need for an abstract base class or mixins, but I will use them if it makes sense.
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HeyImAlex 4518 days ago
"Fat" in this case just means they contain business logic. Many people use their ORM models _exclusively_ as a data layer with no business logic living in the object at all.
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jscn 4518 days ago
Which, if you're following the SRP, is the right thing to do, no?
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edwinnathaniel 4518 days ago
It depends, is it anemic model? or ActiveRecord like model?
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