On Thu, Nov 4, 2010 at 3:38 PM, Nick Coghlan <ncogh...@gmail.com> wrote: > On Thu, Nov 4, 2010 at 4:28 PM, anatoly techtonik <techto...@gmail.com> wrote: >> On Wed, Nov 3, 2010 at 9:08 PM, Glyph Lefkowitz <gl...@twistedmatrix.com> >> wrote: >>> >>> This is the strongest reason why I recommend to everyone I know that they >>> not use pickle for storage they'd like to keep working after upgrades [not >>> just of stdlib, but other 3rd party software or their own software]. :) >>> >>> +1. >>> Twisted actually tried to preserve pickle compatibility in the bad old days, >>> but it was impossible. Pickles should never really be saved to disk unless >>> they contain nothing but lists, ints, strings, and dicts. >> >> But what is alternative in stdlib? >> Don't you think that Python doesn't provide any? > > Python 3.2a3+ (py3k:85817, Oct 24 2010, 19:25:28) > [GCC 4.4.3] on linux2 > Type "help", "copyright", "credits" or "license" for more information. >>>> import json >>>> dir(json) > ['JSONDecoder', 'JSONEncoder', '__all__', '__author__', > '__builtins__', '__cached__', '__doc__', '__file__', '__name__', > '__package__', '__path__', '__version__', '_default_decoder', > '_default_encoder', 'decoder', 'dump', 'dumps', 'encoder', 'load', > 'loads', 'scanner'] > > pickle gets overspecific in many ways, and hence (despite our best > efforts, and those of third parties) may break when changing Python > versions. Serialising to something more language natural (be it JSON, > YAML, XML or one of the multitude of other state encoding formats out > there) is far more likely to be future proof. > > As a tool for communicating between different instances of the *same* > version of Python though, pickle is fine.
pickle is insecure, marshal too. What about JSON? IIUC you need a definition of a class to be able to unserialize it in all cases. I wonder how is this definition validated, i.e. what to watch for when modifying classes that can be serialized. -- anatoly t. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
