openapi: 3.0.2
info:
  title: test
  version: 1.0.0
paths:
  /foo:
    post:
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Foo'
      responses:
        201:
          description: Created

components:
  schemas:
    Foo:
      type: object
      properties:
        foo:
          type: string
          example: bar