def _resource_property_keys(resource):
    """Returns a list of all get_param lookup keys for the given resource.

    :type resource: tuskar.templates.heat.Resource
    :return: list of property names; empty list if none are found
    :rtype: [str]
    """
    keys = []
    for rp in resource.properties:
        if rp.name in ('resource_def', 'resource'):
            for rpv in rp.value['properties'].values():
                if isinstance(rpv, dict) and 'get_param' in rpv:
                    keys.append(rpv['get_param'])
        elif isinstance(rp.value, dict) and 'get_param' in rp.value:
            keys.append(rp.value['get_param'])
    return keys
