[Kotlin][Spring] Response code 200 generated for default responses

[cureaid]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• 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?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

For default responses, a response code of 200 is generated but should be a response code of default.
When there is a response with code 200 in the spec before the default response, then the default response "overrides" the one with the code 200 in the Swagger UI, i.e. the real 200 response description is invisible in the Swagger UI.

openapi-generator version

7.2.0-SNAPSHOT

OpenAPI declaration file content or url

openapi: 3.0.0
info:
  title: example
  version: 0.0.1
paths:
  /pet:
    post:
      responses:
        'default':
          description: foo
          content:
            application/xml:
              schema:
                type: object

Generation Details

docker run --rm -v "${PWD}/output:/output" -v "${PWD}/openapi.yaml:/openapi.yaml" openapitools/openapi-generator-cli generate -i /openapi.yaml -g kotlin-spring -o /output

Steps to reproduce

see above

Actual output

class PetApiController() {

    @Operation(
        summary = "",
        operationId = "petPost",
        description = """""",
        responses = [
            ApiResponse(responseCode = "200", description = "foo", content = [Content(schema = Schema(implementation = kotlin.Any::class))]) ]
    )

Expected output

class PetApiController() {

    @Operation(
        summary = "",
        operationId = "petPost",
        description = """""",
        responses = [
            ApiResponse(responseCode = "default", description = "foo", content = [Content(schema = Schema(implementation = kotlin.Any::class))]) ]
    )

Related issues/PRs

• [BUG] [Java] [spring-boot] Code generated from a specification with a default response indicates the wrong return code #14394

Suggest a fix

Should maybe be done similar to the PR referenced in #14394 .

There is also suspicious code in

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KotlinSpringServerCodegen.java

Line 877 in 457622c

if ("0".equals(resp.code)) {

.

[mdemblani]

I worked on creating a PR for the same: #23833