Tracker for Supported Python versions

[sethmlarson]

Support Matrix for Python / Elastic Stack version

Version	Download Percentage	Currently Supported (7.x)	Supported in Next Major (8.x)
2.7	10.72%	X	X?
3.4	0.07%	X
3.5	1.22%	X
3.6	28.95%	X	X
3.7+	59.04%	X	X
3.x+	89.28%	X	X

The column for "Supported in Next Major" is subject to change until feature freeze of the next major depending on usage.
Data was last updated from downloads for 2021-03-10

Process

Currently we support Python 2.7, and 3.4 onwards as of Elasticsearch v7.x.
Python versions will come out every year however the amount of changes between 3.x to 3.[x + 1] are much smaller than 2 to 3.

Here's the query being used to determine what Python versions should be supported in 8.x by looking at the split of downloads for 7.x:

SELECT
  SUBSTR(details.implementation.version, 1, 3) AS ver,
  COUNT(*) as dwn
FROM `the-psf.pypi.file_downloads`
WHERE
  DATE(timestamp) = "2021-04-22" AND
  file.project = 'elasticsearch' AND
  file.version = '7.12.0' AND 
  # Filter out PyPy versions
  SUBSTR(details.implementation.version, 1, 1) <= '3' AND (
  # Filter out Python 2.6 or earlier
    SUBSTR(details.implementation.version, 1, 1) != '2' OR
    SUBSTR(details.implementation.version, 1, 3) = '2.7'
  ) AND (
  # Filter out Python 3.3 or earlier
    SUBSTR(details.implementation.version, 1, 1) != '3' OR
    SUBSTR(details.implementation.version, 3, 3) >= '4'
  )
GROUP BY ver
ORDER BY dwn DESC

JSON results from Google BigQuery fed into this little script to quickly recalculate:

x = {tuple([int(p) for p in d["ver"].split(".")]): int(d["dwn"]) for d in x}
total = sum(x.values())
x['3.7+'] = sum([v for k, v in x.items() if k >= (3, 7)])
x['3.x+'] = sum([v for k, v in x.items() if isinstance(k, tuple) and k >= (3,)])
for k in list(x.keys()):
    if isinstance(k, tuple) and k >= (3, 7):
        x.pop(k)

for k, v in x.items():
    print(k, f"{v * 100.0 / total:.2f}%")

[sethmlarson]

What we will gain from dropping each version:

• Python 2.7: Python 2 is EOL as of Jan 1, 2020 and many libraries are starting to drop support. Our test suite currently doesn't need any bleeding edge new features but in the future it may.
• Python 3.5: Python 3.6 added inline type hints, f-strings, and async/await. If we are able to make the library 3.6+ I don't see the need to drop Python versions for some time as most Python 3.x versions are very similar post-3.6.

[sethmlarson]

New data from v7.10.0 from December 1st, 2020:

Version	Downloads	Percent
2.7	5583	13.98%
3.4	37	0.09%
3.5	826	2.07%
3.6	13828	34.62%
3.7	12487	31.26%
3.8	6416	16.06%
3.9	758	1.89%
all	39935	100%

[sethmlarson]

New data for v7.11.0 from March 9, 2021:

Version	Percent
2.7	10.72%
3.x+	89.28%
3.4	0.07%
3.5	1.22%
3.6	28.95%
3.7+	59.04%

[sethmlarson]

New data for v7.13.1 from June 16th 2021:

Version	Percent
2.7	8.13%
3.x+	91.87%
3.4	0.09%
3.5	1.89%
3.6	25.47%
3.7+	64.43%

Python 2.7 is less than 10%!