You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: grid_service_serializer.rb
    path of file: ./repos/kontena/server/app/serializers
    
    the code of the file until where you have to start completion: class GridServiceSerializer < KontenaJsonSerializer

  attribute :id
  attribute :created_at
  attribute :cre
    
  def deploy_opts
    deploy_opts = object.deploy_opts
    {
      wait_for_port: deploy_opts.wait_for_port,
      min_health: deploy_opts.min_health,
      interval: deploy_opts.interval
    }
  end