Pyinstaller 应用程序正在访问 txt 文件，但没有写入它们（在应用程序编译之前工作）

Question

settings.txt 在已编译的单文件应用程序中存储和访问，但不会被写入。当文件与脚本位于同一目录中时，这在 Pyinstaller 编译之前有效。

应用程序是从终端编译的：

pyinstaller script.spec script.py --windowed --onefile

a.datas 在规范文件中设置为：

a.datas += [(‘settings.txt’,’/path/to/settings.txt’, "DATA”)]

并且文件在应用程序中被正确读取：

with open(resource_path('settings.txt'), 'r') as f2

但是，当试图覆盖文件时，文件没有更新：

def OnExit(self, event):
    with open(resource_path('settings.txt'), 'w') as f2:
        f2.write('update')

    self.Destroy()

resource_path 定义为：

def resource_path(relative_path):
    """ Get absolute path to resource, works for dev and for PyInstaller """
    try:
        # PyInstaller creates a temp folder and stores path in _MEIPASS
        base_path = sys._MEIPASS
    except Exception:
        base_path = os.environ.get("_MEIPASS2", os.path.abspath("."))

    return os.path.join(base_path, relative_path)

Answer 1

如果您在 Windows 上，_MEIPASS 会返回路径的“短”名称，以防路径的任何组件长度超过 8 个字符。因此，要测试这是否是问题所在，请尝试将其设置为 one-folder 冻结应用，然后将其移动到简单而简短的路径中：例如 C:/test。

如果这是问题所在，您可以通过使用以下方法检索长路径来解决该问题：

if hasattr(sys, '_MEIPASS'):
    import win32api
    sys_meipass = win32api.GetLongPathName(sys._MEIPASS)

Answer 2

我想分享我的解决方案，它同时解决了一般相对路径的许多问题（请参阅函数 __doc__string）。

我有一个名为 top_level_locator.py 的模块，具有修改后的函数 module_path，如其他答案中所见，它采用 relative_path。

在其他 .py 文件中的用法：

from top_level_locator import module_path
resource_location = module_path(relative_path = 'resource.ext')

import sys
from pathlib import Path
from inspect import getsourcefile

def module_path(relative_path):
    """
    Combine top level path location, in this project app.py folder because it serves as main/entry_point, with user relative path.

    NOTE: top_level_locator.py should be in same folder as entry_point.py(/main.py) script 
    - TEST this with executable 
    - TEST this without executable 

    NOTE: care with use of __file__ as it comes with unwarranted side effects when:
    - running from IDLE (Python shell), no __file__ attribute
    - freezers, e.g. py2exe & pyinstaller do not have __file__ attribute! 

    NOTE: care with use of sys.argv[0]
    - unexpected result when you want current module path and get path where script/executable was run from! 

    NOTE: care with use of sys.executable
    - if non-frozen application/module/script: python/path/python.exe 
    - else                                   : standalone_application_executable_name.exe
    """
    # 0 if this module next to your_entry_point.py (main.py) else += 1 for every directory deeper
    n_deep = 1

    print('sys.executable:', sys.executable)
    print('   sys.argv[0]:', Path(sys.argv[0]).parents[n_deep].absolute() / sys.argv[0])
    print('      __file__:', __file__)
    print(' getsourcefile:', Path(getsourcefile(lambda:0)).parents[n_deep].absolute())
    
    if hasattr(sys, "frozen"):
        # retreive possible longpath if needed from _MEIPASS: import win32api; 
        # sys_meipass = win32api.GetLongPathName(sys._MEIPASS)
        base_path = getattr(sys, '_MEIPASS', Path(sys.executable).parent)
        print('      _MEIPASS:', base_path)
        return Path(base_path).joinpath(relative_path)
    return Path(getsourcefile(lambda:0)).parents[n_deep].absolute().joinpath(relative_path)

if __name__ == '__main__':
    module_path()

在非冻结应用程序中，输出将（应该）如下：

• sys.executable: C:\Users\<usr_name>\AppData\Local\Programs\Python\Python37\python.exe
• sys.argv[0]: c:\Users\<usr_name>\Desktop\<project_name>\<project_code_folder>\app.py
• __file__: c:\Users\<usr_name>\Desktop\<project_name>\<project_code_folder>\utils\top_level_locator.py
• getsourcefile: c:\Users\<usr_name>\Desktop\<project_name>\<project_code_folder>

在冻结的应用程序中：

• sys.executable: C:\Users\<usr_name>\Desktop\<project_name>\dist\app.exe
• sys.argv[0]: C:\Users\<usr_name>\Desktop\<project_name>\dist\app.exe
• __file__: C:\Users\<usr_name>\AppData\Local\Temp\_MEI155562\utils\top_level_locator.pyc
• getsourcefile: C:\Users\<usr_name>\Desktop\<project_name>
• _MEIPASS: C:\Users\<usr_name>\AppData\Local\Temp\_MEI155562