filesystem.py

#!/usr/bin/env python
# vim: ai ts=4 sts=4 et sw=4 nu

""" Files manipulation tools

    Shortcuts to retrieve mime type using magic"""

from __future__ import annotations

import os
import pathlib
from collections.abc import Callable
from typing import Any

import magic

# override some MIME-types found by libmagic to different ones
MIME_OVERRIDES = {
    "image/svg": "image/svg+xml",
}


def get_file_mimetype(fpath: pathlib.Path) -> str:
    """MIME Type of file retrieved from magic headers"""

    # detected_mime = magic.detect_from_filename(fpath).mime_type
    # return MIME_OVERRIDES.get(detected_mime, detected_mime)

    with open(fpath, "rb") as fh:
        return get_content_mimetype(fh.read(2048))


def get_content_mimetype(content: bytes | str) -> str:
    """MIME Type of content retrieved from magic headers"""

    try:
        detected_mime = magic.from_buffer(content, mime=True)
        if isinstance(
            detected_mime, bytes
        ):  # pragma: no cover (old python-magic versions where returning bytes)
            detected_mime = detected_mime.decode()
    except UnicodeDecodeError:
        return "application/octet-stream"
    return MIME_OVERRIDES.get(detected_mime, detected_mime)


def delete_callback(
    fpath: str | pathlib.Path,
    callback: Callable | None = None,
    *callback_args: Any,
):
    """helper deleting passed filepath, optionnaly calling an additional callback"""

    os.unlink(fpath)

    # call the callback if requested
    if callback and callable(callback):
        callback.__call__(*callback_args)