The standalone Geo buildpack offers more modern GDAL/GEOS/PROJ library
versions, and can be used by apps in all languages, not just Python:
https://github.com/heroku/heroku-geo-buildpack
As such the Python buildpack's undocumented built-in support was
deprecated back in April 2020, with a scheduled removal date of
6th October 2020:
https://devcenter.heroku.com/changelog-items/1759https://help.heroku.com/D5INLB1A/python-s-build_with_geo_libraries-legacy-feature-is-now-deprecated
Metrics show very few builds continuing to use the built-in support.
Apps with the `BUILD_WITH_GEO_LIBRARIES` env var set will now be shown a
warning directing them to the standalone buildpack, as well as apps that
hit GDAL related pip install errors but aren't using the env var.
This also moves us one step closer to being able to remove
the vendored copy of pip-pop (which is partially broken on
newer pip).
Closes @W-7654424@.
Since the stack is end of life and builds have been disabled:
https://devcenter.heroku.com/changelog-items/1943
There are only two temporarily exempted customers using Python, who
can switch to the Cedar-14 support branch if they still need to build
their Python apps (most of which haven't been built recently).
Closes @W-8054727@.
The compile-time cryptography step that used to use the libffi archives
on S3 was removed in 2018:
https://github.com/heroku/heroku-buildpack-python/commit/c373e80c1285260e5adcbc855f54bbeb6999005c
...since the `cryptography` Python package now ships wheels.
The script is also incorrect, since similar to #964 it only skips builds
for Heroku-16, whereas all stacks since Cedar-14 include libffi-dev in
the build image, so don't need it built/uploaded for later vendoring.
Refs W-7485877.
The `libmemcached` package is available in the base stack image for all
stacks newer than `cedar-14`, so at buildpack compile time the vendor
step is skipped for those stacks:
https://github.com/heroku/heroku-buildpack-python/blob/106f2997fa124852a2a35ee8bfa604ad20c47988/bin/steps/pylibmc#L12-L15
As such, it is not necessary to run the libmemcached bob-builder formula
on newer stacks. The conditional has been updated so it correctly handles
heroku-18 and also the upcoming heroku-20.
An exit code of 1 has been used, otherwise `bob upload` will build and
then upload a zero byte archive to S3, which will go unused.
(This is in comparison to bob formulas that are nested, where an exit
code of 0 is actually desirable, since it allows skipping steps.)
Refs W-7485877.
Co-authored-by: Joe Kutner <jpkutner@gmail.com>
Ed Morley
kennethreitz