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To: python-list@python.org
From: Dieter Maurer <dieter@handshake.de>
Subject: Re: python application file format
Date: Thu, 27 Sep 2012 08:55:20 +0200
References: <5062F9D6.2060402@abzinc.com>
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Xref: csiph.com comp.lang.python:30279

Benjamin Jessup <bsj@abzinc.com> writes:

> ...
> What do people recommend for a file format for a python desktop
> application? Data is complex with 100s/1000s of class instances, which
> reference each other.
>
> ...
> Use cPickle with a module/class whitelist? (Can't easily port, not
> entirely safe, compact enough, expandable)

This is the approach used by the ZODB (Zope Object DataBase).

I like the ZODB. It is really quite easy to get data persisted.
It uses an elaborate caching scheme to speed up database interaction
and has transaction control to ensure persistent data consistency
in case of errors.

Maybe not so relevant in your context, it does not require
locking to safely access persistent data in a multi thread environment.

> ...