openapi: 3.0.3
info:
  title: dummy
  version: 1.0.0
servers:
- url: /
paths:
  /:
    post:
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/__post_request'
      responses:
        "200":
          description: OK
      x-content-type: application/json
      x-accepts:
      - application/json
components:
  schemas:
    schemaA:
      properties:
        propA:
          type: string
      type: object
    __post_request:
      oneOf:
      - $ref: '#/components/schemas/schemaA'
      - additionalProperties: true
        properties: {}
        type: object