udemy-php-cms VS adr-example

The only thing I accept guilty for is overreaction. Sometimes yes, I can't hold it. But if you actually look at the code of those udemy courses, I'd like to see your reaction too. Did you actually look at them? Why every single one teaches you how to allow and SQL injection around overall shitty code as though it's 2003 around, not 2023? Taken from the most fucking popular PHP Udemy course out there.

Adding to the above link a full ADR Example - https://github.com/pmjones/adr-example

Yes, as an example, the First Application's business logic (not that it's much) doesn't tie itself to the framework, as one example. Odan's Slim Skeleton, ADR Example (yes, I know you are the author), and the Aura Payload example class can be seen as other examples.

ADR (as opposed to MVC) - direct link - example

https://github.com/pmjones/adr-example - Follow up example to the above. ADR is an alternative to MVC

More on ADR (like MVC) - https://github.com/pmjones/adr-example

Another option, to me and speaking to the OP as an alternative, it is simpler to add some Data Mappers/Repositories to abstract away the Database code. Good examples is the sample ADR application, Payload library example, Slim 3 First Application, or this Slim 4 Skeleton application

Simple example of a MVC/ADR (Action-Domain-Responder, similar to MVC) system - https://github.com/pmjones/adr-example

Call your class (which doesn't look like a controller anymore...), then, output it to your HTML or JSON renderer, based on the check. You can do this in a class (or 2 - look up ADR - https://github.com/pmjones/adr-example) or in the router.