def create_index(self, index=None, settings=None, es=None):
        """Create new index and ignore if it exists already."""
        if index is None:
            index = self.index
        if es is None:
            es = self.es
        try:
            alias = index
            index = generate_index_name(alias)

            args = {'index': index}
            if settings:
                args['body'] = settings

            es.indices.create(**args)
            es.indices.put_alias(index, alias)
            logger.info('created index alias=%s index=%s' % (alias, index))
        except elasticsearch.TransportError:  # index exists
            pass
Create new index and ignore if it exists already.