Showing the right funcName when wrapping logger functionality in a custom class

Question

This is the formatting string that I am using for logging:

\'%(asctime)s - %(levelname)-10s - %(funcName)s - %(message)s\'

But to show the logg

Answer 1

This is fixed in Python 3.8 with addition of the stacklevel param. However, I took the current implementation of findCaller from cpython to make a Python 3.7 compatible version.

Taken from a combination of the answers above:

import sys,os

#Get both logger's and this file's path so the wrapped logger can tell when its looking at the code stack outside of this file.
_loggingfile = os.path.normcase(logging.__file__)
if hasattr(sys, 'frozen'): #support for py2exe
    _srcfile = "logging%s__init__%s" % (os.sep, __file__[-4:])
elif __file__[-4:].lower() in ['.pyc', '.pyo']:
    _srcfile = __file__[:-4] + '.py'
else:
    _srcfile = __file__
_srcfile = os.path.normcase(_srcfile)
_wrongCallerFiles = set([_loggingfile, _srcfile])

#Subclass the original logger and overwrite findCaller
class WrappedLogger(logging.Logger):
    def __init__(self, name):
        logging.Logger.__init__(self, name)

    #Modified slightly from cpython's implementation https://github.com/python/cpython/blob/master/Lib/logging/__init__.py#L1374
    def findCaller(self, stack_info=False, stacklevel=1):
        """
        Find the stack frame of the caller so that we can note the source
        file name, line number and function name.
        """
        f = currentframe()
        #On some versions of IronPython, currentframe() returns None if
        #IronPython isn't run with -X:Frames.
        if f is not None:
            f = f.f_back
        orig_f = f
        while f and stacklevel > 1:
            f = f.f_back
            stacklevel -= 1
        if not f:
            f = orig_f
        rv = "(unknown file)", 0, "(unknown function)", None
        while hasattr(f, "f_code"):
            co = f.f_code
            filename = os.path.normcase(co.co_filename)
            if filename in _wrongCallerFiles:
                f = f.f_back
                continue
            sinfo = None
            if stack_info:
                sio = io.StringIO()
                sio.write('Stack (most recent call last):\n')
                traceback.print_stack(f, file=sio)
                sinfo = sio.getvalue()
                if sinfo[-1] == '\n':
                sinfo = sinfo[:-1]
            sio.close()
        rv = (co.co_filename, f.f_lineno, co.co_name, sinfo)
        break
    return rv