def METHOD_NAME(self) -> List[str]:
    """
    Retrieve all indices that currently have {elasticsearch_alias} alias
    :return: list of elasticsearch indices
    """
    try:
        indices = self.elasticsearch_client.indices.get_alias(self.elasticsearch_alias).keys()
        return indices
    except NotFoundError:
        LOGGER.warn("Received index not found error from Elasticsearch. " +
                    "The index doesn't exist for a newly created ES. It's OK on first run.")
        # return empty list on exception
        return []