@Size annotation on List<String> causes incorrect openapi spec to be generated.

[caspianb]

Using a simple DTO can reproduce this issue:

static class RequestDto {
    @Size(min = 1, max = 5)
    @Schema(description = "List of values.")
    private List<String> values;
}

The @Size validation is only (correctly) applied to the list size. However, the api spec itself is showing this:

The generated API spec is stating that:

• the list must be between 1 and 5 elements (correct);
• the length of the string of each element must be between 1 and 5 characters (incorrect)

You can also see that the description is also being duplicated from the array down to the element as well. I am uncertain if this is intentional and or desirable so not sure if that should also be considered a bug as well.

[bnasslahsen]

@caspianb,

This looks to be correct.
Anyway, you can ask the swagger-core project for more explanation, as this is purely handled by swagger-core-jakarta

public class DemoApplication {

	record TestDTO(@Size(min = 1, max = 5)
						  @Schema(description = "List of values.")
						  List<String> values) {

	}
	
	public static void main(String[] args) {
		ResolvedSchema resolvedSchema = ModelConverters.getInstance()
				.resolveAsResolvedSchema(
						new AnnotatedType(TestDTO.class).resolveAsRef(false));
		resolvedSchema.schema.getMinLength();
		Assert.isTrue(((ArraySchema) resolvedSchema.schema.getProperties().get("values")).getMaxItems().equals(5));
		Assert.isTrue(((ArraySchema) resolvedSchema.schema.getProperties().get("values")).getItems().getMaxLength().equals(5));
	}
	
}

[caspianb]

Thanks for the quick response! -- I'll log an issue at swagger-core.

This looks to be correct.

Can you explain this to me, though? The item maxLength relates to the String itself. The @Size annotation only applies to the List, though. The String can still be any length (and that's how the spring-boot validations work). It seems like the openApi spec is saying the String must be between 1 and 5 characters -- which is not correct?

(Also note this just started occurring after the 2.2.0 update).

Is there something I'm misunderstanding here?

[bnasslahsen]

@caspianb,

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