[Java] OpenAPI-Spec v3: requestBody schema not used correctly

[janssen92]

Description

When using a requestBody with a type X and a response with type Y in the generated source type Y is used as method parameter as well as method return type.

E.g.:
This method signature is generated:

default ResponseEntity<GetProofingConfigDto> patchProofingConfig(
    @ApiParam(value = "ID of model to return",required=true) @PathVariable("id") String id,
    @ApiParam(value = "Authorization: adminToken for the specific config" ,required=true)
    @RequestHeader(value="Authorization", required=true) String authorization,
    @ApiParam(value = "ProofingFeedback Object" ,required=true )  
    @Valid @RequestBody GetProofingConfigDto UNKNOWN_BASE_TYPE) {

from this specification:

 "patch" : {
        "tags" : [ "proofingConfig" ],
        "summary" : "Patch a ProofingConfig",
        "operationId" : "patchProofingConfig",
        "parameters" : [ {
          "name" : "id",
          ....
          }
        }, {
          "name" : "Authorization",
         ....
          }
        } ],
        "responses" : {
          "200" : {
            "description" : "successful operation",
            "content" : {
              "application/json" : {
                "schema" : {
                  "$ref" : "#/components/schemas/GetProofingConfigDto"
                }
              }
            }
          }
        },
        "requestBody" : {
          "content" : {
            "application/json" : {
              "schema" : {
                "$ref" : "#/components/schemas/PatchProofingConfigDto"
              }
            }
          }
        }

openapi-generator version

3.0.2 (an Master on June 25)

OpenAPI declaration file content or url

https://github.com/janssen92/swagger-feedback-service-api/blob/testOpenApiGenerator/swagger-feedback.json
https://github.com/janssen92/swagger-feedback-service-api/blob/testOpenApiGenerator/swagger-feedback-conf.json

Command line used for generation

java -jar ~/git/openapi-generator/modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -i swagger-feedback.json -g spring -o ~/testOpenApiGen --library spring-boot --config swagger-feedback-conf.json
But also same result with less parameters:
java -jar ~/git/openapi-generator/modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -i swagger-feedback.json -g spring -o ~/testOpenApiGen

Steps to reproduce

• Checkout file(s)
• Generate Code

[jmini]

I had a look at your specification, your request body PatchProofingConfigDto is defined like this:

"components" : {
  "schemas" : {
      "PatchProofingConfigDto" : {
        "allOf" : [ {
          "$ref" : "#/components/schemas/GetProofingConfigDto"
        } ]
      },
      ...
  }
}

I think this is a duplicate of #192 solved in 3.0.3-SNAPSHOT by #358.