aopy - An Aspect Oriented Programming Python Framework

Author - Spencer Herzberg Author - Yuji Fujiki

This framework was built for a graduate software engineering course in Aspect Oriented Programming.

Requirements:

Build a Python AOP framework that corresponds with AspectJ - http://www.eclipse.org/aspectj
Joinpoint model
Pointcut definitions are meant to be simple
Advice: Before, After, Around
Before and after advice are very simple methods
Around advice is very flexible
Dynamic runtime changes to joinpoints
Security measures: define only methods that are "weave-able"

Future Work:

Build in regular expressions for more flexible and dynamic pointcuts
Additional pointcuts for advice.
Eclipse plugin for showing advised code blocks 

How to Use:

1) Import aopy module (AOPWrapper, weaver)
2) Define your own aspect class by inheriting AOPWrapper
3) Optionally define Before, After, Around advice in aspect class
4) Set Before, After, Around advice in aspect class in aspect constructor
5) Set the pointcut for the aspect
    Two ways:
        Define in aspect constructor
        Dynamically call AOPWrapper.setPointcut() on newly created aspect object 
    Rules:
        AOPWrapper.setPointcut(string, string, list)
        Parameter 1: string name of the method you want to advise
        Parameter 2: string number of arguments, 'asterisk' is any number of arguments
        Parameter 3: list of keyword arguments, 'asterisk' is any keyword arguments 
6)Decorate all functions that you may want to advise with @weave decorator (imported from AOPy)

Example Code:

from aopy.core import weave,getPointcutter,AOPWrapper

class Logger(AOPWrapper):

def __init__(self,signature, numargs, kwargs):
    AOPWrapper.__init__(self,signature, numargs, kwargs)
    self.setBefore(self.before)
    self.setAfter(self.after)
    self.setAround(self.around)

def before(self, *args, **kwargs):
    print "before call"

def after(self, retval, exc):
    print "after call"

def around(self,target, method, *args, **kwargs):
    print "before around:",target,method, args, kwargs
    ret = method(*args,**kwargs)
    print "after around: ",ret
    return ret

@weave def run(): print "I'm running"

def main():

#setup logger aspect for all methods named run
#with no args and any kwargs
logger = Logger("run","0", ["*"])

#setup pointcutter singleton
pc = getPointcutter()

#add the logger aspect
pc.addPointcuter(logger)

run()

#runtime reset of logger aspect to a new pointcut
#the next run call to run() will not be advised
logger.setPointcut("notrun","0", ["*"])
run()

main()