heat_template_version: rocky

description: >
  This is a default no-op template which provides empty user-data
  which can be passed to the OS::Nova::Server resources.
  This template can be replaced with a different implementation via
  the resource registry, such that deployers may customize their
  first-boot configuration.

resources:
  userdata:
    type: OS::Heat::MultipartMime

outputs:
  # This means get_resource from the parent template will get the userdata, see:
  # http://docs.openstack.org/developer/heat/template_guide/composition.html#making-your-template-resource-more-transparent
  # Note this is new-for-kilo, an alternative is returning a value then using
  # get_attr in the parent template instead.
  OS::stack_id:
    value: {get_resource: userdata}
