openapi: "3.0.0"
paths:
  /:
    get:
      parameters:
      - name: myPet
        in: query
        required: true
        schema: 
          $ref: "#/components/schemas/Pet"
components:
  schemas:
    Pet:
      description: "a pet"
      type: "string"
      default: dog
      enum:
      - dog
      - cat
      - both