quick method logging

log_methods.py

import collections
import functools


def log_methods(cls):
    def __init__(self, *a, **kw):
        cls.__init__(self, *a, **kw)
        self._log = collections.deque(maxlen=100)

    def logit(method):
        if not callable(method):
            return method

        @functools.wraps(method)
        def g(self, *a, **kw):
            self._log.append((method.__name__, a, kw))
            return method(self, *a, **kw)
        return g

    cls_vars = {
        key: logit(val) for key, val in cls.__dict__.items()
        if not key.startswith('__') }
    cls_vars['__init__'] = __init__

    return type(cls.__name__ + "Logged", (cls,), cls_vars)


if __name__ == "__main__":
    @log_methods
    class T(object):
        def __init__(self, a, b):
            self.a, self.b = a, b

        def foo(self, c, d):
            pass

        def bar(self, e):
            pass

    t = T(1, 2)
    t.foo(3, 4)
    t.bar(e=5)
    print t._log

# deque([('foo', (3, 4), {}), ('bar', (), {'e': 5})], maxlen=100)