Some loaded extension modules have no __file__ value, causing e.g. runtime issue with WinRT packages (bleak / bleak_winrt)

Hello,

I have an issue when running a WinRT-dependent application built with Nuitka. This issue was already reported as #1184 but was closed for inactivity.

Environment

• I installed Python 3.9 using the official Windows 64bit installer from python.org.
• Nuitka was installed using pip in a virtualenv.

Versions:

(__env__) C:\Users\vm0\Desktop\issue-nuitka>python -m nuitka --version
0.6.19.6
Commercial: None
Python: 3.9.5 (tags/v3.9.5:0a7dcbd, May  3 2021, 17:27:52) [MSC v.1928 64 bit (AMD64)]
Flavor: Unknown
Executable: C:\Users\vm0\Desktop\issue-nuitka\__env__\Scripts\python.exe
OS: Windows
Arch: x86_64
WindowsRelease: 10

I also tried on another Windows 10 machine + Python 3.10 but I do not have access to it right now. 😃

Step to reproduce

Here is a minimal example to reproduce.

requirements.txt:

bleak==0.14.2
bleak-winrt==1.1.1
Nuitka==0.6.19.6

test.py:

#!/usr/bin/env python3

import bleak

make.bat:

nuitka ^
    --follow-imports ^
    --assume-yes-for-downloads ^
    --standalone ^
    test.py

• install dependencies (in a venv): pip install -r requirements.txt
• build the test: .\make.bat
• run the test: .\test.dist\test.exe

Output:

(__env__) C:\Users\vm0\Desktop\issue-nuitka>test.dist\test.exe
Traceback (most recent call last):
  File "C:\Users\vm0\Desktop\ISSUE-~1\TEST~1.DIS\test.py", line 3, in <module>
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 986, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
  File "C:\Users\vm0\Desktop\ISSUE-~1\TEST~1.DIS\bleak\__init__.py", line 78, in <module bleak>
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 986, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
  File "C:\Users\vm0\Desktop\ISSUE-~1\TEST~1.DIS\bleak\backends\winrt\scanner.py", line 7, in <module bleak.backends.winrt.scanner>
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 986, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
  File "C:\Users\vm0\Desktop\ISSUE-~1\TEST~1.DIS\bleak_winrt\windows\devices\bluetooth\__init__.py", line 177, in <module bleak_winrt.windows.devices.bluetooth>
AttributeError: 'NoneType' object has no attribute 'BluetoothAdapter'

Workaround

To workaround the issue, I patched the .\__env__\Lib\site-packages\bleak_winrt\__init__.py file from:

# WARNING: Please don't edit this file. It was generated by Python/WinRT v1.0.0-alpha.6

from . import _winrt

def _import_ns_module(ns):
    import importlib.machinery
    import importlib.util

    try:
        module_name = "_bleak_winrt_" + ns.replace('.', '_')

        loader = importlib.machinery.ExtensionFileLoader(module_name, _winrt.__file__)
        spec = importlib.util.spec_from_loader(module_name, loader)
        module = importlib.util.module_from_spec(spec)
        loader.exec_module(module)
        return module
    except Exception:
        return None

to:

# WARNING: Please don't edit this file. It was generated by Python/WinRT v1.0.0-alpha.6

from . import _winrt

import os
_winrt.__file__ = os.path.join(os.path.dirname(__file__), "_winrt.pyd")

def _import_ns_module(ns):
    import importlib.machinery
    import importlib.util

    try:
        module_name = "_bleak_winrt_" + ns.replace('.', '_')

        loader = importlib.machinery.ExtensionFileLoader(module_name, _winrt.__file__)
        spec = importlib.util.spec_from_loader(module_name, loader)
        module = importlib.util.module_from_spec(spec)
        loader.exec_module(module)
        return module
    except Exception:
        return None

The issue was caused by the missing __file__ attribute on the _winrt object.

---

Do not hesitate if you need more info or if you want I test things… 😃

[kayhayen]

As an aside, I would like to thank you for attempting to track this down yourself.

[davidleon]

cefpython3 also has problems with missing file. currently the build fails at File “helpers.pyx”, line 60, in cefpython_py38.GetModuleDirectory. the code in cefpython3 is path = os.path.dirname(os.path.realpath(file)).