我从t
类型的api收到一个物体Object
。我无法腌制它,得到错误:
File "p.py", line 55, in <module>
pickle.dump(t, open('data.pkl', 'wb'))
File "/usr/lib/python2.6/pickle.py", line 1362, in dump
Pickler(file, protocol).dump(obj)
File "/usr/lib/python2.6/pickle.py", line 224, in dump
self.save(obj)
File "/usr/lib/python2.6/pickle.py", line 313, in save
(t.__name__, obj))
pickle.PicklingError: Can't pickle 'Object' object: <Object object at 0xb77b11a0>
当我执行以下操作时:
for i in dir(t): print(type(i))
我只得到字符串对象:
<type 'str'>
<type 'str'>
<type 'str'>
...
<type 'str'>
<type 'str'>
<type 'str'>
如何打印Object
对象的内容以了解为什么它不能被腌制?
它也有可能是对象包含指向QT对象的C指针,在这种情况下,我对pickle对象没有意义。但我想再次看到对象的内部结构,以便建立这个。
您可能想要阅读qazxsw poi并随后检查您的API qazxsw poi课程。
关于“对象的内部结构”,通常实例属性存储在python docs属性中(因为类属性不是pickle,你只关心实例属性) - 但请注意,你还必须递归检查每个属性都有Object
s。
我会使用__dict__
,它有工具来调查对象内部导致目标对象无法被选择的工具。请参阅此答案以获取示例:__dict__
,此Q&A是实际使用的检测工具的示例:dill
。
Good example of BadItem in Dill Module
但是,最常见的出发点是使用pandas.algos._return_false causes PicklingError with dill.dump_session on CentOS:
>>> import dill
>>> x = iter([1,2,3,4])
>>> d = {'x':x}
>>> # we check for unpicklable items in d (i.e. the iterator x)
>>> dill.detect.baditems(d)
[<listiterator object at 0x10b0e48d0>]
>>> # note that nothing inside of the iterator is unpicklable!
>>> dill.detect.baditems(x)
[]
trace
还具有跟踪指针引用和对象引用的功能,因此您可以构建对象如何相互引用的层次结构。见:>>> dill.detect.trace(True)
>>> dill.detect.errors(d)
D2: <dict object at 0x10b8394b0>
T4: <type 'listiterator'>
PicklingError("Can't pickle <type 'listiterator'>: it's not found as __builtin__.listiterator",)
>>>
或者,还有:cloudpickle.py和debugpickle.py,它们大部分都不再开发了。我是dill
的作者,并希望尽快合并https://github.com/uqfoundation/dill/issues/58中缺少的这些代码中的任何功能。
我试过Dill,但它没有解释我的问题。相反,我使用了dill
中的以下代码,这恰好显示了我的dill
覆盖中的错误:
https://gist.github.com/andresriancho/15b5e226de68a0c2efd0
编辑:这是我的代码的再现,使用pickle和cPickle:
__getattribute__
输出:
def debug_pickle(instance):
"""
:return: Which attribute from this object can't be pickled?
"""
attribute = None
for k, v in instance.__dict__.iteritems():
try:
cPickle.dumps(v)
except:
attribute = k
break
return attribute
你会看到原因是因为class myDict(dict):
def __getattribute__(self, item):
# Try to get attribute from internal dict
item = item.replace("_", "$")
if item in self:
return self[item]
# Try super, which may leads to an AttribueError
return super(myDict, self).__getattribute__(item)
myd = myDict()
try:
with open('test.pickle', 'wb') as myf:
cPickle.dump(myd, myf, protocol=-1)
except:
print traceback.format_exc()
try:
with open('test.pickle', 'wb') as myf:
pickle.dump(myd, myf, protocol=-1)
except:
print traceback.format_exc()
正在破坏属性名称
这是Traceback (most recent call last):
File "/Users/myuser/Documents/workspace/AcceptanceTesting/ingest.py", line 35, in <module>
cPickle.dump(myd, myf, protocol=-1)
UnpickleableError: Cannot pickle <class '__main__.myDict'> objects
Traceback (most recent call last):
File "/Users/myuser/Documents/workspace/AcceptanceTesting/ingest.py", line 42, in <module>
pickle.dump(myd, myf, protocol=-1)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.py", line 1370, in dump
Pickler(file, protocol).dump(obj)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.py", line 224, in dump
self.save(obj)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/pickle.py", line 313, in save
(t.__name__, obj))
PicklingError: Can't pickle 'myDict' object: {}
的扩展,在Python 3中。
它:
__getattribute__
,以便您查看调用哪些成员来解决问题。使用Alastair's solution它只是打印.x[i].y.z....
,因为键或值可能是问题,使得更难(但不是不可能)引用dict
中的特定键或值。[key/val type=...]
,dict
和list
,需要单独处理,因为它们没有tuple
属性。dict