[Twisted-Python] A Proposal for reducing the burden of developing on Twisted by dropping Python 2 support

[Scott, Barry]

On Monday, 25 March 2019 10:15:22 GMT Amber Brown wrote:
> Hi everyone,
> 
> Since the Python 2 EOL date is rapidly approaching, I thought it was
> time we consider dropping Python 2 support.
> 
> I personally find that Python 2 compat adds a huge amount of overhead
> when working on and maintaining Twisted, and think that with the current
> maintainer availability, dropping it sooner rather than later would have
> a beneficial effect on how much work we spend on shims/compat,
> complexity, and our ability to ship new features, as well as onboarding
> people who are interested in the project, but have no interest (or
> experience!) in Python 2.7.
> 
> It is basically summed up by doing a feature freeze on an agreed-upon
> version of Twisted, that will be the last version released for 2.7. It
> would be abnormal in that it would get security fixes (our current
> policy is to only release them for current versions) and critical
> bugfixes, but would otherwise be frozen.
> 
> One of my rationales is that from some analysis of PyPI download
> statistics, the vast majority of Python 2 users are using old versions
> of Twisted, while nearly all our Python 3 users are on the latest
> version. As such, I believe freezing a version that will get security
> updates but no new features would not be a massive loss to those stuck
> on Python 2 for whatever reason.
> 
> Twisted's compatibility policy would still apply, ensuring that Python
> 2/3 compatible software using Twisted would be able to use the older
> Twisted version on Python 2, and the newer version on Python 3, as you
> would usually expect.
> 
> You can find the proposal here, in this handy-dandy Google Doc:
> https://docs.google.com/document/d/1S4CGgZC09blLIdk3Zo7wBa75A9_JuuH_3akkyjN0
> lik/edit
> 
> Comments are welcome, as well as which timeline seems reasonable.

We are stuck on python2.7 for the foreseeable future and you will not see us 
in the PyPi stats. We download your release tar ball and build an RPM from it.
We also have to build python2.7 our selves as we are stuck on Centos 6.8.

Having a legacy twisted with critical bugs and security fixes would work for 
us.

Barry