| |
| """Functions for reporting filesizes. Borrowed from https://github.com/PyFilesystem/pyfilesystem2 |
| |
| The functions declared in this module should cover the different |
| usecases needed to generate a string representation of a file size |
| using several different units. Since there are many standards regarding |
| file size units, three different functions have been implemented. |
| |
| See Also: |
| * `Wikipedia: Binary prefix <https://en.wikipedia.org/wiki/Binary_prefix>`_ |
| |
| """ |
|
|
| __all__ = ["decimal"] |
|
|
| from typing import Iterable, List, Tuple |
|
|
|
|
| def _to_str(size: int, suffixes: Iterable[str], base: int) -> str: |
| if size == 1: |
| return "1 byte" |
| elif size < base: |
| return "{:,} bytes".format(size) |
|
|
| for i, suffix in enumerate(suffixes, 2): |
| unit = base ** i |
| if size < unit: |
| break |
| return "{:,.1f} {}".format((base * size / unit), suffix) |
|
|
|
|
| def pick_unit_and_suffix(size: int, suffixes: List[str], base: int) -> Tuple[int, str]: |
| """Pick a suffix and base for the given size.""" |
| for i, suffix in enumerate(suffixes): |
| unit = base ** i |
| if size < unit * base: |
| break |
| return unit, suffix |
|
|
|
|
| def decimal(size: int) -> str: |
| """Convert a filesize in to a string (powers of 1000, SI prefixes). |
| |
| In this convention, ``1000 B = 1 kB``. |
| |
| This is typically the format used to advertise the storage |
| capacity of USB flash drives and the like (*256 MB* meaning |
| actually a storage capacity of more than *256 000 000 B*), |
| or used by **Mac OS X** since v10.6 to report file sizes. |
| |
| Arguments: |
| int (size): A file size. |
| |
| Returns: |
| `str`: A string containing a abbreviated file size and units. |
| |
| Example: |
| >>> filesize.decimal(30000) |
| '30.0 kB' |
| |
| """ |
| return _to_str(size, ("kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"), 1000) |
|
|
