Python dynamically add decorator to class' methods by decorating class

Question

say I have a class:

class x:

    def first_x_method(self):
        print \'doing first_x_method stuff...\'

    def second_x_method(self):
        print \'d         


        

Answer 1

Here's a version of the trace decorator implemented as a class which allows for the other use case asked for: passing in the function to decorate all member functions of the decorated class with.

import inspect


def log(func):
    def wrapped(*args, **kwargs):
        try:
            print "Entering: [%s] with parameters %s" % (func.__name__, args)
            try:
                return func(*args, **kwargs)
            except Exception, e:
                print 'Exception in %s : %s' % (func.__name__, e)
        finally:
            print "Exiting: [%s]" % func.__name__
    return wrapped


class trace(object):

    def __init__(self, f):
        self.f = f

    def __call__(self, cls):
        for name, m in inspect.getmembers(cls, inspect.ismethod):
            setattr(cls, name, self.f(m))
        return cls


@trace(log)
class X(object):

    def first_x_method(self):
        print 'doing first_x_method stuff...'

    def second_x_method(self):
        print 'doing second_x_method stuff...'

x = X()
x.first_x_method()
x.second_x_method()