[issue11705] sys.excepthook doesn't work in imported modules
Changes by Claudiu Popa pcmantic...@gmail.com: -- resolution: - not a bug stage: - resolved status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
Changes by Éric Araujo mer...@netwok.org: -- nosy: +Valery.Lesin, amaury.forgeotdarc, benjamin.peterson, haypo, pitrou ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
STINNER Victor victor.stin...@haypocalc.com added the comment: python -c import loggingTest calls PyRun_SimpleStringFlags(). python import_loggingTest.py (import_loggingTest.py just contains import loggingTest) calls PyRun_SimpleFileExFlags(). Both functions calls PyErr_Print() on error. An error occurs (raise Exception in loggingTest.py) while importing the module, in PyImport_ExecCodeModuleEx(). The real problem is that the module is cleared because it raised an error. Extract of PyImport_ExecCodeModuleEx: v = PyEval_EvalCode((PyCodeObject *)co, d, d); if (v == NULL) goto error; ... error: remove_module(name); (remove_module() does something like del sys.modules['loggingTest']: because there is only once reference, the destructor of the module is called) -- You can workaround this corner case by keeping a reference to all used objects using a closure: --- def create_closure(logger, print_exception): def handleException(excType, excValue, traceback): print_exception(excType, excValue, traceback) print inside exception handler: logger = %s % logger logger.error(Uncaught exception, exc_info=(excType, excValue, traceback)) return handleException sys.excepthook = create_closure(logger, tb.print_exception) --- -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
New submission from Elias Zamaria mikez...@gmail.com: I am trying to design a Python program that logs all uncaught exceptions using the logging module. I am doing this by using the sys.excepthook function to override the default exception handling. I noticed that if I run the program directly from the command line, it works fine, but if I try to import the file, it doesn't work. It seems like the sys.excepthook function is unaware of the logging module. Here is an example: #! /usr/bin/env python2.7 import logging, sys logger = logging.getLogger() logger.setLevel(logging.DEBUG) logger.addHandler(logging.FileHandler(test.log)) print outside of exception handler: logger = %s % logger def handleException(excType, excValue, traceback): #global logger # this function doesn't work whether or not I include this line print inside exception handler: logger = %s % logger logger.error(Uncaught exception, exc_info=(excType, excValue, traceback)) sys.excepthook = handleException logger.debug(starting) asdf# create an exception If I run this from the command line (`./loggingTest.py`), it works fine. The exception gets logged, and I see this output: outside of exception handler: logger = logging.RootLogger object at 0x7f2022eab950 inside exception handler: logger = logging.RootLogger object at 0x7f2022eab950 However, if I run the Python interpreter and try to import the file (`import loggingTest`), it acts strangely. The exception doesn't get logged and I see this: outside of exception handler: logger = logging.RootLogger object at 0x7f8ab04f3ad0 inside exception handler: logger = None Error in sys.excepthook: Traceback (most recent call last): File loggingTest.py, line 13, in handleException logger.error(Uncaught exception, exc_info=(excType, excValue, traceback)) AttributeError: 'NoneType' object has no attribute 'error' Original exception was: Traceback (most recent call last): File stdin, line 1, in module File loggingTest.py, line 18, in module asdf# create an exception NameError: name 'asdf' is not defined I can maybe work around this problem by importing the logging module again within sys.excepthook, but I am still curious: why is this happening? The above text was copied from my question on Stack Overflow (http://stackoverflow.com/questions/5451746/sys-excepthook-doesnt-work-in-imported-modules). Someone on there (Jochen Ritzel) has mentioned that he noticed this bug in Python 2.7.1 but not 2.7. To me, it seems like the sys.excepthook function is unaware of any imported modules, unless those modules are imported from inside the function. -- components: Library (Lib) files: loggingTest.py messages: 132437 nosy: mikez302 priority: normal severity: normal status: open title: sys.excepthook doesn't work in imported modules type: behavior versions: Python 2.7 Added file: http://bugs.python.org/file21446/loggingTest.py ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
Andreas Stührk andy-pyt...@hammerhartes.de added the comment: I really doubt that this issue has anything to do with `sys.excepthook` at all. It's rather that module members are set to `None` during module cleanup. Because the module raises an exception when one tries to import it, it will be cleaned up immediately (see `PyImport_ExecCodeModuleEx`: it calls `remove_module` which will call at some point `_PyModule_Clear`). At the time when `sys.excepthook` is called, all module members are already set to `None`. One can easily demonstrate that this is really the problem by removing the exception raise in your example code: If one then imports loggingTest in an interactive session and raises an exception, the expected behaviour can be observed. Another workaround is to bind `logger` as a default argument (i.e. ``def handleException(excType, excValue, traceback, logger=logger):``). -- nosy: +Trundle ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
Elias Zamaria mikez...@gmail.com added the comment: Andreas, your explanation seems plausible. What has changed between 2.7 and 2.7.1 such that doing the same thing produces different results? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
Andreas Stührk andy-pyt...@hammerhartes.de added the comment: The difference between 2.7 and 2.7.1 is issue #10068 (e2aa3b1d08bc). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
Elias Zamaria mikez...@gmail.com added the comment: Is my issue a bug or is it expected behavior? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
[issue11705] sys.excepthook doesn't work in imported modules
Andreas Stührk andy-pyt...@hammerhartes.de added the comment: In my opinion, it is expected behaviour (but then, I'm not a core developer). -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue11705 ___ ___ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
