On Wed, Feb 26, 2020 at 3:29 PM Kenneth Knowles <k...@apache.org> wrote: > > Are these divergent enough that they all need to consume testing resources? > For example can lower priority versions be daily runs or some such?
For the 3.x series, I think we will get the most signal out of the lowest and highest version, and can get by with smoke tests + infrequent post-commits for the ones between. > Kenn > > On Wed, Feb 26, 2020 at 3:25 PM Robert Bradshaw <rober...@google.com> wrote: >> >> +1 to consulting users. Currently 3.5 downloads sit at 3.7%, or about >> 20% of all Python 3 downloads. >> >> I would propose getting in warnings about 3.5 EoL well ahead of time, >> at the very least as part of the 2.7 warning. >> >> Fortunately, supporting multiple 3.x versions is significantly easier >> than spanning 2.7 and 3.x. I would rather not impose an ordering on >> dropping 3.5 and adding 3.8 but consider their merits independently. >> >> >> On Wed, Feb 26, 2020 at 3:16 PM Kyle Weaver <kcwea...@google.com> wrote: >> > >> > 5 versions is too many IMO. We've had issues with Python precommit >> > resource usage in the past, and adding another version would surely >> > exacerbate those issues. And we have also already had to leave out certain >> > features on 3.5 [1]. Therefore, I am in favor of dropping 3.5 before >> > adding 3.8. After dropping Python 2 and adding 3.8, that will leave us >> > with the latest three minor versions (3.6, 3.7, 3.8), which I think is >> > closer to the "sweet spot." Though I would be interested in hearing if >> > there are any users who would prefer we continue supporting 3.5. >> > >> > [1] >> > https://github.com/apache/beam/blob/8658b95545352e51f35959f38334f3c7df8b48eb/sdks/python/apache_beam/runners/portability/flink_runner.py#L55 >> > >> > On Wed, Feb 26, 2020 at 3:00 PM Valentyn Tymofieiev <valen...@google.com> >> > wrote: >> >> >> >> I would like to start a discussion about identifying a guideline for >> >> answering questions like: >> >> >> >> 1. When will Beam support a new Python version (say, Python 3.8)? >> >> 2. When will Beam drop support for an old Python version (say, Python >> >> 3.5)? >> >> 3. How many Python versions should we aim to support concurrently >> >> (investigate issues, have continuous integration tests)? >> >> 4. What comes first: adding support for a new version (3.8) or >> >> deprecating older one (3.5)? This may affect the max load our test >> >> infrastructure needs to sustain. >> >> >> >> We are already getting requests for supporting Python 3.8 and there were >> >> some good reasons[1] to drop support for Python 3.5 (at least, early >> >> versions of 3.5). Answering these questions would help set expectations >> >> in Beam user community, Beam dev community, and may help us establish >> >> resource requirements for test infrastructure and plan efforts. >> >> >> >> PEP-0602 [2] establishes a yearly release cycle for Python versions >> >> starting from 3.9. Each release is a long-term support release and is >> >> supported for 5 years: first 1.5 years allow for general bug fix support, >> >> remaining 3.5 years have security fix support. >> >> >> >> At every point, there may be up to 5 Python minor versions that did not >> >> yet reach EOL, see "Release overlap with 12 month diagram" [3]. We can >> >> try to support all of them, but that may come at a cost of velocity: we >> >> will have more tests to maintain, and we will have to develop Beam >> >> against a lower version for a longer period. Supporting less versions >> >> will have implications for user experience. It also may be difficult to >> >> ensure support of the most recent version early, since our dependencies >> >> (e.g. picklers) may not be supporting them yet. >> >> >> >> Currently we support 4 Python versions (2.7, 3.5, 3.6, 3.7). >> >> >> >> Is 4 versions a sweet spot? Too much? Too little? What do you think? >> >> >> >> [1] https://github.com/apache/beam/pull/10821#issuecomment-590167711 >> >> [2] https://www.python.org/dev/peps/pep-0602/ >> >> [3] https://www.python.org/dev/peps/pep-0602/#id17
