Validating persistence model
Here’s how this final interface looks: With this batch of interfaces, we’ve managed to define in a jiffy a simple – yet efficient – set of granular contracts which allow you to swap out concrete domain object implementations, as if we were using Lego blocks.
Next we need to hydrate our model with some interface implementers; let’s see now how to accomplish this in a fairly painless way.
Well, in fact it does, albeit at the expenses of having to tackle the aforementioned issues.
But claims like this must be always backed up with a decent proof of concept, so, allow me to provide a few examples.
Quite often, simple PHP Domain Models are composed of a few POPOs (Plain Old PHP Objects), which encapsulate rich business logic, like validation and strategy, behind a clean API.
With that said, let’s see how to translate the conceptual stuff to tangible PHP code.
In this course, Shawn Wildermuth will show you the best practices for using entities, validation, and view models. NET project, knowing how to handle data and validation can be confusing.
But throwing blame to the patterns for what they’re intended to do is nothing but a weak excuse for not embracing a Domain Model according to the purpose it was conceived in the first place: Of course, the above definition is a world away from being formal. First off, creating a rich Domain Model, where multiple domain objects with well-defined constraints and rules interact, can be a daunting task.
Second, not only is it necessary to define from top to bottom the model itself, but it’s also necessary to implement from scratch or reuse a mapping layer in order to move data back and forward between the persistence layer and the model in question.
Here’s the first one: is to define a narrow contract for generic post objects which should have a one-to-many relationship with the related comments.
Since the interface’s code speaks for itself, let’s go one step further and create another interface to specify the contract for the corresponding comments: method, which appeals to the whip of Interface Injection for binding a user to a specific comment.
Phrases like view-models, data transfer objects and entities are thrown about casually and some developers can be confused about what to use when. Shawn Wildermuth has been tinkering with computers and software since he got a Vic-20 back in the early '80s.