py2exe doesn't find imported win32com.shell module, and creates invalid distribution without this file. As a result, an application that uses this module may crash at random or miss some features.
For example version 0.2 of winshell.py from Tim Golden (a thin wrapper around Windows Shell-Functions) starts with:
py2exe reports that something is missing:
The following modules appear to be missing ['Interface', 'intSet', 'mxDateTime.__version__', 'win32com.shell']
and starting the program leaves:
Traceback (most recent call last): File "xxxxxx.py", line 33, in ? File "xxxxxxx.pyo", line 9, in ? File "winshell.pyo", line 27, in ? ImportError: No module named shell
in the log.file.
win32com does some magic in order to allow loading of COM extensions during run time. The actual extensions reside in the win32comext directory under site-packages and can't be loaded directly. win32com's __path__ variable has been changed to point to both win32com and win32comext. py2exe's modulefinder can't handle runtime changes in __path__ so we have to tell it about the change beforehand.
Without shame I browsed Spambayes source code and found the code to fix it.
1 # ... 2 # ModuleFinder can't handle runtime changes to __path__, but win32com uses them 3 try: 4 # py2exe 0.6.4 introduced a replacement modulefinder. 5 # This means we have to add package paths there, not to the built-in 6 # one. If this new modulefinder gets integrated into Python, then 7 # we might be able to revert this some day. 8 # if this doesn't work, try import modulefinder 9 try: 10 import py2exe.mf as modulefinder 11 except ImportError: 12 import modulefinder 13 import win32com, sys 14 for p in win32com.__path__[1:]: 15 modulefinder.AddPackagePath("win32com", p) 16 for extra in ["win32com.shell"]: #,"win32com.mapi" 17 __import__(extra) 18 m = sys.modules[extra] 19 for p in m.__path__[1:]: 20 modulefinder.AddPackagePath(extra, p) 21 except ImportError: 22 # no build path setup, no worries. 23 pass 24 25 from distutils.core import setup 26 import py2exe 27 28 # ... 29 # The rest of the setup file. 30 # ...
And this worked.
The following products included workaround:
py2exe should detect such well-known problems with well-known modules, and when win32com.shell is missing, a workaround should be automatically applied with a corresponding log message:
The following modules appear to be missing ['Interface', 'intSet', 'mxDateTime.__version__', 'win32com.shell'] Applying automatic workaround for known problem with win32com.shell
py2exe should also fail if required modules are missing unless some --force key in effect.