| In my view, there's duplication that could use an abstraction and duplication that is merely coincidental. (See The Wrong Abstraction by Sandi Metz [1]) Unless something screams "this should be the single source of truth about this" forget abstracting all together and just copy and move on. The problem with trying to create 1 "CRUD controller" is that there are always going to be hairy things that make parts one offs. Perhaps someone needs to add location headers because the underlying calculation takes too long. Perhaps they want custom status codes when things go wrong. Maybe they need to use web sockets or server sent events. As soon as any sort of needed customization comes into play you start finding yourself closer and closer to the framework you are likely using until you reach a point of "Why am I trying to wrap the entire framework? Why can't I use it directly?" And if you've made the mistake of pulling that abstraction into a library, heaven help you when you need to update things. What happens if the underlying framework library makes a breaking change? Or if you need to make a breaking change to support some feature? It all gets really messy really fast and now instead of just impacting the 1 application you are impacting 100. Updating shared code is never as easy as you might think. But, on the flip side, I can't think of anything easier, even if it's mostly boiler plate, than writing a controller that calls some business logic that works with a DB. Regardless the language or framework. The hard part of such applications is always the business logic and not the actual controller wiring. [1] https://sandimetz.com/blog/2016/1/20/the-wrong-abstraction |
If you're designing a backend service that has multiple "heads" - say, a web application and a mobile application. Then it makes sense that service should be code that manipulates the database(s) via business logic, and at the very least should be in one place.
But broadly, programmers do see value in abstracting interacting with the DB at least somewhat. It's why ORMs exist.
I don't know if there's a real answer. An abstraction can be right for a while and then become wrong when you add a new requirement right? So is it pointless to use abstractions at all? That definitely feels like the wrong takeaway. I guess instead, it's don't immediately abstract out anything that feels abstractable when writing new code and don't feel obliged to use existing abstractions in a codebase until you're sure they fit what you're doing.