Python pickle的类内似乎会出现问题，但在命令行脚本中不会

Question

我一直在试图从数据库中取出一些词典。我又回到了使用marshal模块，但仍在想为什么pickle在取消数据序列化方面遇到了如此困难。下面是一个命令行python会话，它基本上显示了我要做的事情：

>>> a = {'service': 'amazon', 'protocol': 'stream', 'key': 'lajdfoau09424jojf.flv'}
>>> import pickle; import base64
>>> pickled = base64.b64encode(pickle.dumps(a))
>>> pickled
'KGRwMApTJ3Byb3RvY29sJwpwMQpTJ3N0cmVhbScKcDIKc1Mna2V5JwpwMwpTJ2xhamRmb2F1MDk0MjRqb2pmLmZsdicKcDQKc1Mnc2VydmljZScKcDUKUydhbWF6b24nCnA2CnMu'
>>> unpickled = pickle.loads(base64.b64decode(pickled))
>>> unpickled
{'protocol': 'stream', 'service': 'amazon', 'key': 'lajdfoau09424jojf.flv'}
>>> unpickled['service']
'amazon'

这一切都很好，但是当我在一个类的工厂方法中尝试这种方法时，它看起来像酸洗负荷零件出错。我要加载的字符串的酸洗方式与上述相同。我甚至尝试过复制上面命令行会话中pickle的确切字符串，并尝试取消pickle，但没有成功。下面是后一种尝试的代码：

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Answer 1

你的代码有效。你是怎么测试的？在

import logging
import base64
import pickle
class Resource:
    @staticmethod
    def resource_factory(resource_data):
        resource_data = "KGRwMApTJ3Byb3RvY29sJwpwMQpTJ3N0cmVhbScKcDIKc1Mna2V5JwpwMwpTJ2xhamRmb2F1MDk0MjRqb2pmLmZsdicKcDQKc1Mnc2VydmljZScKcDUKUydhbWF6b24nCnA2CnMu" #hack to just see if we can unpickle this string
        # logging.debug("Creating resource: " + resource_data)
        unencoded = base64.b64decode(resource_data)
        # logging.debug("Unencoded is: " + unencoded)
        unpacked = pickle.loads(unencoded)
        logging.debug("Unpacked: " + repr(unpacked))
        service = unpacked['service']
        protocol = unpacked['protocol']
        key = unpacked['key']

logging.basicConfig(level=logging.DEBUG)
Resource.resource_factory('')

收益率

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