python 多个装饰器组合应用，实现面向切面之AOP编程

首先，需要对上面几篇介绍的2个callHandler （PerformanceCountCallHandler， CacheCallHandler）进行改写。

代码如下：

#-*- coding: UTF-8 -*-
#-------------------------------------------------------------------------------
# Name:        模块2
# Purpose:
#
# Author:      ankier
#
# Created:     22-12-2012
# Copyright:   (c) Ankier 2012
# Licence:     <2012~2020>
#-------------------------------------------------------------------------------
import time

from functools import wraps

_Cache ={}

def PerformanceCountCallHandler():
def _PerformanceCountCallHandler(originalFunc):
def __PerformanceCountCallHandler(fun):
def wrap(args, kw):
glos = originalFunc.func_globals
package = glos['__package__']
model = glos['__name__']
methodName = originalFunc.func_name

timeStart = time.time()

result = fun(args, kw)

timeEnd = time.time()

print 'package:',package,' , model:', model, ' , methodName:',methodName,'. ', timeEnd - timeStart, 's'

return result
return wrap
return __PerformanceCountCallHandler
return _PerformanceCountCallHandler

#-*- coding: UTF-8 -*-
#-------------------------------------------------------------------------------
# Name:        模块2
# Purpose:
#
# Author:      ankier
#
# Created:     22-12-2012
# Copyright:   (c) Ankier 2012
# Licence:     <2012~2020>
#-------------------------------------------------------------------------------
import time
import hashlib
import pickle
import sys

from functools import wraps

_Cache ={}

def __HashParamsKey(function, args, kw):
glos = function.func_globals
package = glos['__package__']
model = glos['__name__']
methodName = function.func_name

key = pickle.dumps((package, model, methodName, args, kw))
return hashlib.sha1(key).hexdigest()

def __IsObsolete(entry, duration):
return time.time() - entry['time'] > duration

def CacheCallHandler(duration = sys.maxint):
def _CacheCallHandler(originalFunc):
def __CacheCallHandler(fun):
def wrap(args, kw):
key = __HashParamsKey(originalFunc, args, kw)
if key not in _Cache or __IsObsolete(_Cache[key], duration):
#保存结果
result = fun(args, kw)
_Cache[key] = {'value': result,
'time': time.time()}

return _Cache[key]['value']
return wrap
return __CacheCallHandler
return _CacheCallHandler

需要一个管理和注册多种装饰器的注册装饰器。

#-*- coding: UTF-8 -*-
#-------------------------------------------------------------------------------
# Name:        registerDecorators
# Purpose:
#
# Author:      ankier
#
# Created:     23-12-2012
# Copyright:   (c) Ankier 2012
# Licence:     <2012~2020>
#-------------------------------------------------------------------------------

def RegisterDecorators(*_decorators):
def _RegisterDecorators(func):
wrap = func
for _deco in _decorators:
__deco = _deco(func)
wrap = __deco(wrap)
return wrap
return _RegisterDecorators

下面看如何使用这些类，cache 在前面， performance handler 在后面。

使用方式如下：

#-*- coding: UTF-8 -*-

import time
from performanceCountCallHandler import PerformanceCountCallHandler
from cacheCallHandler import CacheCallHandler
from registerDecorators import RegisterDecorators

@RegisterDecorators(CacheCallHandler(10000), PerformanceCountCallHandler())
def Sum(xx , yy ):
sum = xx + yy
print '------Execute Sum----- '
time.sleep(5)
return sum

@RegisterDecorators(CacheCallHandler(1), PerformanceCountCallHandler())
def Count(xx , yy ):
sum = xx + yy
print '------Execute Count----- '
time.sleep(5)
return sum

运行效果：

------Execute Sum-----
package: None  , model: mainFrame  , methodName: Sum .  5.0 s
9
package: None  , model: mainFrame  , methodName: Sum .  0.0 s
9
------Execute Count-----
package: None  , model: mainFrame  , methodName: Count .  5.0 s
2
------Execute Count-----
package: None  , model: mainFrame  , methodName: Count .  5.0 s
3
------Execute Count-----
package: None  , model: mainFrame  , methodName: Count .  5.01600003242 s
2