etcdutils.py 文件源码

def delete_empty_parents(client, child_dir, root_key, timeout=DEFAULT_TIMEOUT):
    """
    Attempts to delete child_dir and any empty parent directories.

    Makes a best effort.  If any of the deletes fail, gives up.  This
    method is safe, even if another client is writing to the directory (the
    delete will fail if the directory becomes non-empty).

    :param client: EtcdClient
    :param child_dir: Key to delete, along with its parents, should be a
           directory.
    :param root_key: Prefix of child_key to stop at.  Will not be deleted.
    :param timeout: Timeout to use on the etcd delete operation.
    """
    _log.debug("Deleting empty directories from %s down to %s", child_dir,
               root_key)
    path_segments = child_dir.strip("/").split("/")
    root_path_segments = root_key.strip("/").split("/")
    if path_segments[:len(root_path_segments)] != root_path_segments:
        raise ValueError("child_key %r must start with root key %r" %
                         (child_dir, root_key))
    for num_seg_to_strip in xrange(len(path_segments) -
                                   len(root_path_segments)):
        key_segments = path_segments[:len(path_segments) - num_seg_to_strip]
        key_to_delete = "/".join(key_segments)
        try:
            client.delete(key_to_delete, dir=True, timeout=timeout)
        except etcd.EtcdKeyNotFound:
            _log.debug("Key %s already deleted", key_to_delete)
            continue
        except etcd.EtcdDirNotEmpty:
            _log.debug("Directory %s not empty, giving up", key_to_delete)
            break
        except etcd.EtcdException as e:
            _log.warning("Failed to delete %s (%r), skipping.",
                         key_to_delete, e)
            break