logging - Better way to log method calls in Python?

Question

We can code out some sort of logging decorator to echo function/method calls like the following:

def log(fn):
    ...

@log
def foo():
    ...

class Foo(object):
    @log
    def foo(self):
        ...

    @log
    def bar(self, a, b):
        ...

    @log
    def foobar(self, x, y, z):
        ...

But what if we are like to log method calls without putting that many @log in front of each meth definition? Is there some way to just put one decorator above a class definition to make all its method calls decorated/logged? Or are there some other better and interesting ways to do that instead of decorator?

Answer 1

This might be overkill, but there is a trace function facility that will inform you of a great deal of activity within your program:

import sys

def trace(frame, event, arg):
    if event == "call":
        filename = frame.f_code.co_filename
        if filename == "path/to/myfile.py":
            lineno = frame.f_lineno
            # Here I'm printing the file and line number, 
            # but you can examine the frame, locals, etc too.
            print "%s @ %s" % (filename, lineno)
    return trace

sys.settrace(trace)
call_my_function()
sys.settrace(None)