What is the best practice for structureing complex OOP in components

Question

When building a complex component I sometimes find that my models can grow too large and I'd like to refactor them into into multiple classes that properly separate concerns. In the core I've only ever seen components where the entirety of the business logic sits within a model, perhaps offloading some utilities to helpers. Are there any examples in the core where a model is split into multiple classes?

Does Joomla have best practices for where to put classes and how to load classes which can work together to provide the model logic?

Answer 1

The obvious examples in the core, and most tutorials I have seen, do split the Model between the List and Edit for the plural or singular processing of record(s). And that seems too obvious an answer but unfortunately I haven't seen anything else specific to point you too.

This is not a claim to 'best practice' but in my own code I tend to be creating a Model based on a table or data type these days for as much of the business process/logic and use Traits to share a lot of the common code to do with handling the CRUD aspects to keep things manageable.

For example I have an InventoryModel for sharing all processing related to Product Inventory records whether they are internal sources or from external sources. I might still use the single model, view, controller approach to list or edit a form but any actions beyond the basic save/close and sorting/filter will find their way back to the InventoryModel or InventoryController.

I have also used mycomponent/src/library as a place to store classes that are used to create more complete or functional objects to handle classes that fall between a Model and utility type Helper class. That may be an option for reducing the code in your Models.

My self taught approach does have a lot of code in the Controller classes that really should be in the Models as I have learnt more about better coding so if anything my Models should get more code in them as I clean up things to meet the thin controller approach.

Another approach I tend to be following nowadays is to have the majority of the processing in my Admin Models and keep the Site, API or CLI Models to a application specific requirement by either extending or Use'ing the Admin Model where possible. It reduces the duplication of code in my models and problem diagnosis is easier.

As I try to 'modularise' my components I found it easier to specifically define what I want to load with a USE or boootComponent statement rather they rely on Joomla's automagic to resolve class names.