---
other:
  - |
    The jinja2 template rendering function is extensended with a ``raise``
    method. This can be used to raise errors conditionally in the Jinja2
    templated tripleo-heat-tempaltes, for example in case some required property
    is not defined in roles_data or network_data. The following example
    demonstrates how to raise an error conditionally in a template::

      {%- if condition %}
        {{ raise('MESSAGE') }}
      {%- endif %}