It's fundamentally different than REST, sure. Its not fundamentally different than "REST" that abandons resource-oriented hypermedia.
> REST is not completely undone just because you want validation.
REST includes a validation model (indeed, its centered around one.)
It is completely undone when you toss that out and replace it with a different one.
> Without a schema or DDL, you're still validating but you're doing it in code.
With a schema or DDL, you are validating in code. It may be code in an external library or tool, but that's just a possibility with any validation model, whether its Schema-based, or Media-type-based (as in REST), or based on something else.
Yes.
> It's fundamentally different.
It's fundamentally different than REST, sure. Its not fundamentally different than "REST" that abandons resource-oriented hypermedia.
> REST is not completely undone just because you want validation.
REST includes a validation model (indeed, its centered around one.)
It is completely undone when you toss that out and replace it with a different one.
> Without a schema or DDL, you're still validating but you're doing it in code.
With a schema or DDL, you are validating in code. It may be code in an external library or tool, but that's just a possibility with any validation model, whether its Schema-based, or Media-type-based (as in REST), or based on something else.