监控程序执行时间并将其写入日志的脚本

# /usr/bin/python
# -*- coding:utf-8 -*-


from time import time

def logged(when):
    def log(f,*args,**kargs):
        print  '''
                  called:
                    functions:%s
                    args: %r
                    kargs: %r
        '''   % (f,args,kargs)
    
    def pre_logged(f):
        def wrapper(*args,**kargs):
            log(f,*args,**kargs)
            return f(*args,**kargs)
        return wrapper

    def post_logged(f):
        def wrapper(*args,**kargs):
            now = time()
            try:
                return f(*args,**kargs)
            finally:
                log(f,*args,**kargs)
                print "time delta:%s" % (time()-now)
        return  wrapper

    try:
        return {"pre":pre_logged,"post":post_logged}[when]
    except KeyError,e:
        raise ValueError(e),'must be "pre" or "post"'


@logged("post")
def hello(name):
    print "hello,",name

hello("world!")


'''
等同于： hello = logged("post")(hello("world!"))
'''