用于 Windows 的 Python chmod答案

【问题标题】：Python chmod for windows用于 Windows 的 Python chmod
【发布时间】：2020-05-25 03:07:21
【问题描述】：

我正在尝试为 Windows 创建带有替换字体的 Skype 修补程序（股票错误地将日文汉字显示为中文等效）。也许 Python 不是最好的选择，但当前的问题与 Python 本身无关：asar 实用程序产生具有只读权限的输出，而更改权限尝试无能为力。但是，也许 os.chmod 不能在 Windows 上运行？


import tkinter as tk
from tkinter import filedialog
import subprocess
import os
import shutil


def change_permissions_recursive(path, mode):
    for root, dirs, files in os.walk(path, topdown=False):
        for dir in [os.path.join(root,d) for d in dirs]:
            os.chmod(dir, mode)
    for file in [os.path.join(root, f) for f in files]:
            os.chmod(file, mode)


root = tk.Tk()
root.withdraw()
dir_path = filedialog.askdirectory(initialdir="C:\Program Files (x86)\Microsoft\Skype for Desktop")
cmd = "asar.cmd extract \"" + dir_path + "/resources/app.asar\" tmp/app"
process = subprocess.Popen(cmd, stdout=subprocess.PIPE, creationflags=0x08000000, cwd="utils")
process.wait()
change_permissions_recursive("utils/tmp/app/fonts", 0o777)
shutil.copyfile("utils/meiryo.ttf", "utils/tmp/app/fonts")

【问题讨论】：

你能显示minimal reproducible example吗？我不确定这个问题是否需要 tkinter
而且 PowerShell 或批处理会比 python“更好”，是的
codepicky.com/hacking-electron-restyle-skype 我正在关注本指南，但 asar 实用程序输出似乎是用错误的权限编写的。但是，也许这就是shutil.copy本身的错误。会用powershell重写
是的，这与 Python 本身有关：使用 powershell 时一切正常

标签： python file-permissions

【解决方案1】：

shutil.copy 本身有问题：用 powershell 重写相同的逻辑时，一切都按预期工作

【讨论】：

【解决方案2】：

是的，chmod 通常不适用于 Windows。

最好从命令行使用适当的工具：cacls 用于旧版本的 Windows（Windows XP 或更低版本），或icacls 用于大多数版本的 Windows。

以下代码可以允许更改权限（如果需要，可以使用额外的上下文管理器临时更改）：

"""
Prototype of script to modify access rights with "icacls" in Windows
"""
from contextlib import contextmanager
from enum import Enum
from subprocess import check_output
from pathlib import Path
from typing import Generator, List


class AccessRight(Enum):
    """Access Rights for files/folders"""

    DELETE = "D"
    FULL = "F"  # Edit Permissions + Create + Delete + Read + Write
    NO_ACCESS = "N"
    MODIFY = "M"  # Create + Delete + Read + Write
    READ_EXECUTE = "RX"
    READ_ONLY = "R"
    WRITE_ONLY = "W"


@contextmanager
def set_access_right(file: Path, access: AccessRight) -> Generator[Path, None, None]:
    """Context Manager to temporarily set a given access rights to a file and reset"""

    def cmd(access_right: AccessRight) -> List[str]:
        return [
            "icacls",
            str(file),
            "/inheritance:r",
            "/grant:r",
            f"Everyone:{access_right.value}",
        ]

    try:
        check_output(cmd(access))
        yield file

    finally:
        check_output(cmd(AccessRight.FULL))


# We create a file (if it does not exist) with empty content
toto = Path("toto.txt")
toto.touch()

# We temporarily set access rights of the
with set_access_right(toto, AccessRight.WRITE_ONLY) as path:
    path.write_text("My name is Toto")
    try:
        content = path.read_text()
        print(f":( Should not be able to read content of file but read: {content}")
    except PermissionError:
        print("Cannot read toto: YEAH!")

# We check that access rights have been restored (and delete the file to stay clean)
print(path.read_text())
toto.unlink()

【讨论】：