[BUG][kotlin-spring] Version >= 5.0.0 generates invalid code on HTTP OPTIONS

[mwatel42]

Description

Starting version 5.0.0, it is impossible to generate compiling code when using HTTP OPTIONS in an API. It used to work just fine as the generated code was using @RequestMapping, defining the RequestMethod.

openapi-generator version

>= 5.0.0

OpenAPI declaration file content

openapi: 3.0.3
info:
  title: kotlin-spring generator bug report
  version: v1

paths:
  /world:
    options:
      operationId: options
      tags:
        - hello
      summary: This will generate code that cannot compile
      responses:
        200:
          description: Hello world!
          content:
            application/json:
              example:
                { }

Generation Details

Generated code looks as follow

/**
 * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech) (5.0.0).
 * https://openapi-generator.tech
 * Do not edit the class manually.
*/
package com.bugreport.api

import org.springframework.http.HttpStatus
import org.springframework.http.MediaType
import org.springframework.http.ResponseEntity

import org.springframework.web.bind.annotation.*
import org.springframework.validation.annotation.Validated
import org.springframework.web.context.request.NativeWebRequest
import org.springframework.beans.factory.annotation.Autowired

import javax.validation.Valid
import javax.validation.constraints.DecimalMax
import javax.validation.constraints.DecimalMin
import javax.validation.constraints.Max
import javax.validation.constraints.Min
import javax.validation.constraints.NotNull
import javax.validation.constraints.Pattern
import javax.validation.constraints.Size

import kotlin.collections.List
import kotlin.collections.Map

@Validated
@RequestMapping("\${api.base-path:}")
interface WorldApi {


    @OptionsMapping(
            value = ["/world"],
            produces = ["application/json"]
    )
    fun options(): ResponseEntity<Unit> {
        return ResponseEntity(HttpStatus.NOT_IMPLEMENTED)
    }
}

Steps to reproduce

openapi-generator-cli generate -i bugreport.yml -g kotlin-spring

Related issues/PRs

#7189 (comment)

Suggest a fix

Rollback.

The previous version was covering all cases, at the price of a bit of verbosity on generated code, which is not an issue. The PR can only work for CRUD operations, but all other HTTP methods were lost as a consequence.

As reference, RequestMethod in Spring is defined as:

public enum RequestMethod {
	GET, HEAD, POST, PUT, PATCH, DELETE, OPTIONS, TRACE
}

Existing Spring annotations are:

@GetMapping
@PostMapping
@PutMapping
@PatchMapping
@DeleteMapping

Anybody using HTTP HEAD, OPTIONS or TRACE will be unable to use the generator.

[sjoblomj]

This was fixed in #9900 and this ticket can be closed.