LocalBackend¶

class mmeval.fileio.LocalBackend[source]¶

Raw local storage backend.

exists(filepath: Union[str, pathlib.Path]) → bool[source]¶

Check whether a file path exists.

Parameters: filepath (str or Path) – Path to be checked whether exists.
Returns: Return True if filepath exists, False otherwise.
Return type: bool

Examples

>>> backend = LocalBackend()
>>> filepath = '/path/of/file'
>>> backend.exists(filepath)
True

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

Read bytes from a given filepath with ‘rb’ mode.

Parameters: filepath (str or Path) – Path to read data.
Returns: Expected bytes object.
Return type: bytes

Examples

>>> backend = LocalBackend()
>>> filepath = '/path/of/file'
>>> backend.get(filepath)
b'hello world'

get_local_path(filepath: Union[str, pathlib.Path]) → Generator[Union[str, pathlib.Path], None, None][source]¶

Only for unified API and do nothing.

Parameters

filepath (str or Path) – Path to be read data.
backend_args (dict, optional) – Arguments to instantiate the corresponding backend. Defaults to None.

Examples

>>> backend = LocalBackend()
>>> with backend.get_local_path('s3://bucket/abc.jpg') as path:
...     # do something here

get_text(filepath: Union[str, pathlib.Path], encoding: str = 'utf-8') → str[source]¶

Read text from a given filepath with ‘r’ mode.

Parameters

filepath (str or Path) – Path to read data.
encoding (str) – The encoding format used to open the filepath. Defaults to ‘utf-8’.

Returns

Expected text reading from filepath.

Return type

str

Examples

>>> backend = LocalBackend()
>>> filepath = '/path/of/file'
>>> backend.get_text(filepath)
'hello world'

isdir(filepath: Union[str, pathlib.Path]) → bool[source]¶

Check whether a file path is a directory.

Parameters: filepath (str or Path) – Path to be checked whether it is a directory.
Returns: Return True if filepath points to a directory, False otherwise.
Return type: bool

Examples

>>> backend = LocalBackend()
>>> filepath = '/path/of/dir'
>>> backend.isdir(filepath)
True

isfile(filepath: Union[str, pathlib.Path]) → bool[source]¶

Check whether a file path is a file.

Parameters: filepath (str or Path) – Path to be checked whether it is a file.
Returns: Return True if filepath points to a file, False otherwise.
Return type: bool

Examples

>>> backend = LocalBackend()
>>> filepath = '/path/of/file'
>>> backend.isfile(filepath)
True

join_path(filepath: Union[str, pathlib.Path], *filepaths: Union[str, pathlib.Path]) → str[source]¶

Concatenate all file paths.

Join one or more filepath components intelligently. The return value is the concatenation of filepath and any members of *filepaths.

Parameters: filepath (str or Path) – Path to be concatenated.
Returns: The result of concatenation.
Return type: str

Examples

>>> backend = LocalBackend()
>>> filepath1 = '/path/of/dir1'
>>> filepath2 = 'dir2'
>>> filepath3 = 'path/of/file'
>>> backend.join_path(filepath1, filepath2, filepath3)
'/path/of/dir/dir2/path/of/file'

list_dir_or_file(dir_path: Union[str, pathlib.Path], list_dir: bool = True, list_file: bool = True, suffix: Optional[Union[str, Tuple[str]]] = None, recursive: bool = False) → Iterator[str][source]¶

Scan a directory to find the interested directories or files in arbitrary order.

Note

list_dir_or_file() returns the path relative to dir_path.

Parameters

dir_path (str or Path) – Path of the directory.
list_dir (bool) – List the directories. Defaults to True.
list_file (bool) – List the path of files. Defaults to True.
suffix (str or tuple[str], optional) – File suffix that we are interested in. Defaults to None.
recursive (bool) – If set to True, recursively scan the directory. Defaults to False.

Yields

Iterable[str] – A relative path to dir_path.

Examples

>>> backend = LocalBackend()
>>> dir_path = '/path/of/dir'
>>> # list those files and directories in current directory
>>> for file_path in backend.list_dir_or_file(dir_path):
...     print(file_path)
>>> # only list files
>>> for file_path in backend.list_dir_or_file(dir_path, list_dir=False):
...     print(file_path)
>>> # only list directories
>>> for file_path in backend.list_dir_or_file(dir_path, list_file=False):
...     print(file_path)
>>> # only list files ending with specified suffixes
>>> for file_path in backend.list_dir_or_file(dir_path, suffix='.txt'):
...     print(file_path)
>>> # list all files and directory recursively
>>> for file_path in backend.list_dir_or_file(dir_path, recursive=True):
...     print(file_path)