LmdbBackend¶

class mmeval.fileio.LmdbBackend(db_path, readonly=True, lock=False, readahead=False, **kwargs)[source]¶

Lmdb storage backend.

Parameters

db_path (str) – Lmdb database path.
readonly (bool) – Lmdb environment parameter. If True, disallow any write operations. Defaults to True.
lock (bool) – Lmdb environment parameter. If False, when concurrent access occurs, do not lock the database. Defaults to False.
readahead (bool) – Lmdb environment parameter. If False, disable the OS filesystem readahead mechanism, which may improve random read performance when a database is larger than RAM. Defaults to False.
**kwargs – Keyword arguments passed to lmdb.open.

db_path¶

Lmdb database path.

get(filepath: Union[str, pathlib.Path]) → bytes[source]¶

Get values according to the filepath.

Parameters: filepath (str or Path) – Here, filepath is the lmdb key.
Returns: Expected bytes object.
Return type: bytes

Examples

>>> backend = LmdbBackend('path/to/lmdb')
>>> backend.get('key')
b'hello world'