[ZODB-Dev] RFC: Python2 - Py3k database compatibility

[Jim Fulton]

On Mon, Apr 29, 2013 at 10:24 AM, Stephan Richter
<stephan.richter at gmail.com> wrote:
> On Monday, April 29, 2013 09:48:05 AM Jim Fulton wrote:
>> I'd like there to a stable 4.0 release **soon**
>> that doesn't use zodbpickle for Python 2.
>
> I would like to agree. But on the other hand, the ZODB release cycles are very
> long and the prospect of waiting another 6-12 months before any Python 3
> support lands, is really scary because it prohibits me to even write a new
> project in Python 3.

As stated here:

https://mail.zope.org/pipermail/zodb-dev/2012-October/014770.html

I was hoping that the breakup of the ZODB packages would allow
us to increase the tempo of releases.

But increasing tempo is only possible of master is stable.


> (CH has just invested about 6 man-months into the porting
> effort and without ZODB we are basically stuck. But we do not need a transition
> plan, since we can recreate our ZODBs from configuration files.)
>
> Could we compromise and support Python 3 in ZODB 4.0 without necessarily solve
> all the migration strategy issues?

I suggested that in the part fo my email that you snipped.

> In fact, by using zodbpickle, zodbpickle
> can have a separate, faster release cycle experimenting with some transition
> strategies. Maybe one way to install ZODB 4.0 would be to not use zodbpickle
> and use cPickle instead. We already have all that stuff separated into a
> _compat module, so that should not be too hard.

Right. As I suggested, let's get to a point where we can get a stable ZODB 4.0
release for Python 2.  As soon as we get that, let's get a ZODB 4.0.x or 4.1
release that works on Python 3, presumably via zodbpickle.

While we want to make progress on Python 3, we can't hold
ZODB hostage to the Python 3 porting effort.

Jim

-- 
Jim Fulton
http://www.linkedin.com/in/jimfulton