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

As suggested in the first answer, subclassing the Logger class and using logging.setLoggerClass should do the trick. You will need a modified findCaller function, that is handling your wrapped function call(s).

Put the following into a module, since the findCaller class method is searching the first call from a file, which is not the current source filename.

import inspect
import logging
import os

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)

class WrappedLogger(logging.Logger):
    def __init__(self,name):
        logging.Logger.__init__(self, name)

    def findCaller(self):
        """
        Find the stack frame of the caller so that we can note the source
        file name, line number and function name.
        """
        # get all outer frames starting from the current frame
        outer = inspect.getouterframes(inspect.currentframe())
        # reverse the order, to search from out inward
        outer.reverse()
        rv = "(unknown file)", 0, "(unknown function)"    

        pos = 0
        # go through all frames
        for i in range(0,len(outer)):
            # stop if we find the current source filename
            if outer[i][1] == _srcfile:
                # the caller is the previous one
                pos=i-1
                break

        # get the frame (stored in first tuple entry)
        f = outer[pos][0]

        co = f.f_code
        rv = (co.co_filename, f.f_lineno, co.co_name)

        return rv
# Usage:
logging.setLoggerClass(WrappedLogger)
log = logging.getLogger("something")