On Thu, 2015-04-16 at 09:54 -0400, Ken Giusti wrote:
> Hi all,
>
> I'm building on the work done by Dominic and Mickael to get all the proton
> python bits to work under both python2 and python3. See [1].
>
> I think this will entail a lot of little changes to the python sources and
> the unit tests. Rather than check in a single huge patch, I'm going to break
> it up over several patches.
>
> The first bunch of patches will simply 'modernize' the existing python code.
> Old style syntax that is not forward compatible with python 3 will be
> replaced (eg. print "foo" --> print("foo"), etc). I'll use a tool called
> 'futurize' which is part of the python future toolset [2], [3].
>
> Once all python code is updated, then I'll begin introducing python 3
> specific patches, including the work already done by Dominic and Mickael. Of
> course I'll verify that none of these changes will break python 2. I've got
> a local CI system that can build/test in both environments.
>
> From a discussion with Dominic, we agreed that it would be A Good Thing to
> use one of the existing Py2 <--> Py3 abstraction libraries. These libraries
> provide utilities for writing code that works under both python versions.
> I've used 'six' in the past [4] and found it quite helpful - it will
> eliminate a lot of the messy conditional code one has to hack in order to
> support both languages.
>
> However, this library is not part of the standard python library. This means
> introducing a new dependency.
>
> Personally, I don't think this is a big deal - use of 'six' is ubiquitous
> among python packages. It's available freely via pypi, and though most
> distros.
>
> So that's the Big Question - is everyone comfortable with this additional
> dependency? Does anyone have a better alternative? Has anyone ported other
> large python codebases - what was your experience?
>
> thanks,
>
> -K
>
>
> [1] https://issues.apache.org/jira/browse/PROTON-490
> [2] http://python-future.org/index.html
> [3] http://python-future.org/futurize_cheatsheet.html
> [4] https://pythonhosted.org/six/
>
+1. The fact that six is a single python file means we can easily fork
it into proton if the dependency becomes a problem (which it probably
wont.)
