Python实现简单的缓存和缓存decorator，pythondecorator,一个简单的缓存实现，将缓

Python实现简单的缓存和缓存decorator，pythondecorator,一个简单的缓存实现，将缓

一个简单的缓存实现，将缓存数据保存在单例的对象中。

使用方法：

    # Initialize    SimpleCache({'data':{'example':'example data'}})    # Getting instance    c = SimpleCache.getInstance()    c.set('re.reg_exp_compiled',re.compile(r'\W*'))    reg_exp = c.get('re.reg_exp_compiled',default=re.compile(r'\W*'))    # --------------------------------------------------------------    c = SimpleCache.getInstance()    reg_exp = c.getset('re.reg_exp_compiled',re.compile(r'\W*'))    # --------------------------------------------------------------        @scache    def func1():        return 'OK'

实现

__author__ = "Andrey Nikishaev"__copyright__ = "Copyright 2010, http://creotiv.in.ua"__license__ = "GPL"__version__ = "0.3"__maintainer__ = "Andrey Nikishaev"__email__ = "creotiv@gmail.com"__status__ = "Production""""Simple local cache.It saves local data in singleton dictionary with convenient interfaceExamples of use:    # Initialize    SimpleCache({'data':{'example':'example data'}})    # Getting instance    c = SimpleCache.getInstance()    c.set('re.reg_exp_compiled',re.compile(r'\W*'))    reg_exp = c.get('re.reg_exp_compiled',default=re.compile(r'\W*'))or    c = SimpleCache.getInstance()    reg_exp = c.getset('re.reg_exp_compiled',re.compile(r'\W*'))or    @scache    def func1():        return 'OK'"""class SimpleCache(dict):    def __new__(cls,*args):        if not hasattr(cls,'_instance'):            cls._instance = dict.__new__(cls)        else:            raise Exception('SimpleCache already initialized')        return cls._instance    @classmethod    def getInstance(cls):        if not hasattr(cls,'_instance'):            cls._instance = dict.__new__(cls)        return cls._instance    def get(self,name,default=None):        """Multilevel get function.        Code:                Config().get('opt.opt_level2.key','default_value')        """        if not name:             return default        levels = name.split('.')        data = self                    for level in levels:            try:                            data = data[level]            except:                return default        return data    def set(self,name,value):        """Multilevel set function        Code:                Config().set('opt.opt_level2.key','default_value')        """        levels = name.split('.')        arr = self                for name in levels[:-1]:            if not arr.has_key(name):                         arr[name] = {}               arr = arr[name]        arr[levels[-1]] = value    def getset(self,name,value):        """Get cache, if not exists set it and return set value        Code:                Config().getset('opt.opt_level2.key','default_value')        """        g = self.get(name)        if not g:            g = value            self.set(name,g)        return gdef scache(func):    def wrapper(*args, **kwargs):        cache = SimpleCache.getInstance()        fn = "scache." + func.__module__ + func.__class__.__name__ + \             func.__name__ + str(args) + str(kwargs)                val = cache.get(fn)        if not val:            res = func(*args, **kwargs)            cache.set(fn,res)            return res        return val    return wrapper