openapi: 3.0.0
info:
  title: Example of links with callbacks
  version: 0.9.0
paths:
  /hooks:
    post:
      requestBody:    
        description: body provided by consumer with callback URL
        required: true
        content:
          application/json:
            example:
              callback-url: https://consumer.com/hookcallback
      responses:      
        '201':
          description: Successfully subscribed
          content:
            application/json:
              example:
                hookId: 23432-32432-45454-97980
          links:
            unsubscribe:
              operationId: cancelHookCallback
              parameters: 
                id: $response.body#/hookId
      callbacks:
        hookEvent:
          '$request.body#/callback-url':
            post:
              requestBody:
                content:
                  application/json:
                    example:
                      message: Here is the event
              responses:
                '200':
                  description: Expected responses from callback consumer
  /hooks/{id}:
    delete:
      operationId: cancelHookCallback
      parameters:
        name: id
        in: path
        schema: 
          type: string
      responses:
        '200':
          description: Successfully cancelled callback