How to write all class variables to disk with dill

2019-07-26 01:52发布

问题:

I'm trying to store a couple of objects for restart purposes in a code I'm writing. They are fairly complex, with several layers of classes contained within them, including classes that use class variables. I need this all to be restored when I dill.load() it back up.

Unfortunately, there's a very specific thing that I'm doing that seems to not work with dill.

I've created a test case that exhibits the problem:

basic.py:

class Basic(object):
    x = 10
    def __init__(self, initial=False):
        super(Basic, self).__init__()
        self.y = 4
        Basic.z = 5

make_dill.py:

import dill
from basic import Basic
b = Basic()
with open('basic', 'wb') as f:
    dill.dump(b, f)
with open('basic', 'rb') as f:
    b = dill.load(f)
print('basic', b.x, b.y, b.z)

un_dill.py:

import dill
with open('basic', 'rb') as f:
    b = dill.load(f)
print('basic', b.x, b.y, b.z)

It works fine when it is all run from the same file (make_dill.py), but when I try to read the file basic in un_dill.py:

AttributeError: 'Basic' object has no attribute 'z'

So for some reason it isn't capturing the class variable z that is assigned during initialization of an instance. It does however capture the class variable x that is assigned right in the class definition.

What am I missing here? I need to save the complete state of these objects.

In the sparse dill documentation, it says