Dynamically reload a class definition in Python

Question

I've written an IRC bot using Twisted and now I've gotten to the point where I want to be able to dynamically reload functionality.

In my main program, I do from bots.google import GoogleBot and I've looked at how to use reload to reload modules, but I still can't figure out how to do dynamic re-importing of classes.

So, given a Python class, how do I dynamically reload the class definition?

Answer 1

I figured it out, here's the code I use:

def reimport_class(self, cls):
    """
    Reload and reimport class "cls".  Return the new definition of the class.
    """

    # Get the fully qualified name of the class.
    from twisted.python import reflect
    full_path = reflect.qual(cls)

    # Naively parse the module name and class name.
    # Can be done much better...
    match = re.match(r'(.*)\.([^\.]+)', full_path)
    module_name = match.group(1)
    class_name = match.group(2)

    # This is where the good stuff happens.
    mod = __import__(module_name, fromlist=[class_name])
    reload(mod)

    # The (reloaded definition of the) class itself is returned.
    return getattr(mod, class_name)