[renke1]

I can't recommend OpenAPI/Swagger-based code generation at all based on my experience working with it. I've only used it for Java, Kotlin and TypeScript, but the generated code (usually more then you asked for) only works like 90% of the time and getting it to 100% takes workaround after workaround. A really frustrating experience.

I must say, however, that it may work for simple APIs but even then usually only for generating the model part and not the API part. What kind of worked for me though was generating code for the server in form of a Kotlin interface for a Spring MVC controller. Although, here too, I had to modify the code generator templates to tailor it to my needs.

Regarding API client, when you can successfully generate an API client with code generation, it should be considered a low-level API client upon which one should build a high-level and more user-friendly API client (e.g. object model with actual methods and not only anemic objects).