Store object using Python pickle, and load it into different namespace

Question

I\'d like to pass object state between two Python programs (one is my own code running standalone, one is a Pyramid view), and different namespaces. Somewhat related questio

Answer 1

Use dill instead of pickle, because dill by default pickles by serializing the class definition and not by reference.

>>> import dill
>>> class MyClass:
...   def __init__(self): 
...     self.data = set()
...     self.more = dict()
...   def do_stuff(self):
...     return sorted(self.more)
... 
>>> c = MyClass()
>>> c.data.add(1)
>>> c.data.add(2)
>>> c.data.add(3)
>>> c.data
set([1, 2, 3])
>>> c.more['1'] = 1
>>> c.more['2'] = 2
>>> c.more['3'] = lambda x:x
>>> def more_stuff(self, x):  
...   return x+1
... 
>>> c.more_stuff = more_stuff
>>> 
>>> with open('my_c.pik', "wb") as f:
...   dill.dump(c, f)
... 
>>> 

Shut down the session, and restart in a new session…

Python 2.7.8 (default, Jul 13 2014, 02:29:54) 
[GCC 4.2.1 Compatible Apple Clang 4.1 ((tags/Apple/clang-421.11.66))] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import dill
>>> with open('my_c.pik', "rb") as f:
...   c = dill.load(f)
... 
>>> c.data
set([1, 2, 3])
>>> c.more
{'1': 1, '3':  at 0x10473ec80>, '2': 2}
>>> c.do_stuff()
['1', '2', '3']
>>> c.more_stuff(5)
6

Get dill here: https://github.com/uqfoundation/dill