[PATCHES] Port pytalloc to Python 3

[Richard Sharpe]

On Mon, Dec 8, 2014 at 12:24 PM, Jelmer Vernooij <jelmer at samba.org> wrote:
> On Mon, Dec 08, 2014 at 02:33:10PM -0500, Simo wrote:
>> > > Forcing people to recompile Python 3 on those systems just to get Samba
>> > > to run on them seem a little bit excessive. (And please do not propose
>> > > to embed a version of python3 in our sources or my head will explode! :)
>> > I agree shipping Python3 sources is a terrible idea. :-)
>> >
>> > This would only affect those people that want a new *major* version of Samba
>> > and run an OS that ships Python2 but not Python3, in a year from now. Is
>> > that really going to affect more than a handful of people?
>>
>> Yes.
> What kind of users? Which specific platforms are they on? Platforms
> like IRIX and AIX don't bundle any version of Python as far as I know.

Almost every appliance out there is using CentOS/RHEL 6 of some sort
because CentOS 7 only came out recently.

> Are there really many people compiling new Samba major releases from scratch on
> RHEL 6, without using some third party package repository?

A lot are, in my experience, and many of them are using Samba 3.6.x.
What happens is they cannot use the packages supplied with
RHEL/CentOS, and they have their own modules etc. While Samba 3.6 can
do out-of-tree module builds, Samba 4.x cannot, as far as I can see.
We kind of shot ourselves in the foot there.

Some are using 4.1.x and one group I know of are using Samba 4.2 (master).

>> > If these users are really an issue, then let's just wait some more time until
>> > we attempt a migration from Python2 to Python3.
>>
>> We are being simultaneously being pushed to python3 by bleeding edge
>> distros (like Fedora) and being pulled back by trailing ones.
>> I do not think postponing is a solution.
> We could postpone for a while longer since as you say, Python2 will
> probably be around for some time to come. That said, I am also not convinced
> we couldn't get away with dropping Python2 support.
>
>> > > I think the only reasonable way to go to have a smooth transition for
>> > > our downstreams is to support both Python2 and Python3 in our code for
>> > > at least a coupe of years.
>> > This means a lot of overhead for Samba developers over a couple of years,
>> > without a clear benefit.
>>
>> Can we quantify this overhead ?
> We'll need to run our testsuite with both Python versions to prevent
> regressions.
>
> The overhead of writing code that works on both Python2 and Python3 is hard to
> quantify but there are quite a few major differences and some subtle
> differences, especially in C bindings. All of these take up extra time when
> writing bindings and Python code. We'll have to deal with testsuite failures
> because code only runs on one Python.
>
>> I have 2 projects that build on both python2 and python3 and I do not
>> see a significant overhead.
> What kind of projects, and how large?
>
> I've worked in a couple of projects that support Python2 and Python3
> and been a part of attempts to bilingualize others. In every situation it's
> made the development process more complicated and frustrating.
>
> Jelmer



-- 
Regards,
Richard Sharpe
(何以解憂？唯有杜康。--曹操)