[ALL] parameter name for post body must be 'body'

Description

in Swagger version 2, it was possible to specify a name for the body parameter in the yaml...

      parameters:
        - in: body
          name: instanceInputs
          required: true
          description: The inputs to use to create instances from the parent definition.
          schema:
            $ref: '#/definitions/CreateExternalWorkflowInstances'

which after generation yielded a name for the parameter...

def create_external_workflows_instances(self, uid, instance_inputs, **kwargs):  # noqa: E501

with the update to open api 3.0, this no longer appears to be possible...

      requestBody:
        content:
          application/json:
            schema:
              $ref: "#/components/schemas/CreateExternalWorkflowInstances"
        description: The inputs to use to create instances from the parent definition.
        required: true

and the parameter name for the body seems to be stuck as 'body'.

def create_external_workflows_instances(self, body, uid, **kwargs):  # noqa: E501

using 'body' as the parameter name is ok as a default but it is 'leaking' the implementation detail (the fact that the value is passed in the http body of a post) into the programatic api. It should be (and was previously) possible to change this default.

Swagger-codegen version

3.0.5

Swagger declaration file content or url

  "/workflows/instances/external/{uid}":
    parameters:
      - name: uid
        in: path
        required: true
        schema:
          type: string
    post:
      summary: Create external workflow instance(s) based on an external definition
      operationId: create_external_workflows_instances
      requestBody:
        content:
          application/json:
            schema:
              $ref: "#/components/schemas/CreateExternalWorkflowInstances"
        description: The inputs to use to create instances from the parent definition.
        required: true
      responses:
        "200":
          description: Success
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Bookmark"
      security:
        - api_key:
            []
      tags:
        - workflows_instances

Command line used for generation

swagger-codegen generate -DmodelTests=false -DapiDocs=false -DmodelDocs=false -i ./procanswonhttp-py/swonSwagger.yaml -l python -o ./procanswonhttp-py --additional-properties packageName=procanswonhttp

Related issues/PRs

Issue #9103 pertains to the order of the body parameter which is also an issue for me

Reproduce the issue with the supplied OpenAPI declaration and the shown swagger-codegen command, then inspect the generated Python method signature. Compare the OpenAPI 3 requestBody handling with the Swagger 2 body-parameter behavior and review related issue #9103. Done means the generated API exposes an appropriate configurable body argument without regressing parameter ordering.