[BUG] useBeanValidation is always false

[Sa1ZeR]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

If you use library with the spring-http-interface value, useBeanValidation and performBeanValidation are always false. Consequently, validation annotations are not generated in DTO classes.
If you use spring-cloud, everything works correctly.

openapi-generator version

7.21.0

OpenAPI declaration file content or url

[zaenk]

I was just about to open another PR to copy the defaults from spring-http-interface to spring-cloud, because I think for an HTTP client lib those defaults are the correct ones.

On the controller side, yes, there's a need for validation, but on the client side, what's the point of running runtime validation on a response which was integrated based on a contract?

I'm curious about the use case. One thing that comes to mind is users using spring-cloud but also implementing the generated API interface as a WebMVC controller—I think that's not the intent of the generated code here. A better approach that also respects single responsibility would be to generate the MVC interfaces with bean validation using the spring-boot library, and separately generate the Feign clients with the spring-cloud library (or HTTP clients with the http-interface library) without validation into a different package. In this case, POJOs and API interfaces are duplicated, yes, but they serve different purposes. It's better to avoid unnecessary validations on responses performance-wise.