openapi: "3.0.0"
info:
  version: 1.0.0
  title: Swagger Petstore
paths:
  /pets:
    patch:
      requestBody:
        $ref: '#/components/requestBodies/CreatePetRequestBody'
      responses:
        '200':
          description: Updated
  
components:
  requestBodies:
    CreatePetRequestBody:
      content:
        application/json:
          schema:
            oneOf:
              - $ref: '#/components/schemas/Cat'
              - $ref: '#/components/schemas/Dog'
  schemas:
    Dog:
      type: object
      properties:
        bark:
          type: boolean
        breed:
          type: string
          enum: [Dingo, Husky, Retriever, Shepherd]
    Cat:
      type: object
      properties:
        hunts:
          type: boolean
        age:
          type: integer

oapi-codegen -package api -generate types,client pet.openapi.yaml > client.gen.go

type ClientWithResponsesInterface interface {
	...
	PatchPetsWithResponse(ctx context.Context, body PatchPetsJSONRequestBody, reqEditors ...RequestEditorFn) (*PatchPetsResponse, error)
}

// PatchPetsJSONRequestBody defines body for PatchPets for application/json ContentType.
type PatchPetsJSONRequestBody PatchPetsJSONBody

// PatchPetsJSONBody defines parameters for PatchPets.
type PatchPetsJSONBody struct {
	union json.RawMessage
}

// CreatePetRequestBody defines model for CreatePetRequestBody.
type CreatePetRequestBody struct {
	union json.RawMessage
}