ImportError: cannot import name 'Feature'

[Marcin Juszkiewicz]

One of Horizon's requirements is pyscss package. Which had last release over 4 years ago...

Two days ago setuptools v46 got released. One of changes was drop of Features feature.

Now Kolla builds fail:

INFO:kolla.common.utils.horizon:Collecting pyScss===1.3.4
INFO:kolla.common.utils.horizon: Downloading http://mirror.ord.rax.opendev.org:8080/pypifiles/packages/1d/4a/221ae7561c8f51c4f28b2b172366ccd0820b14bb947350df82428dfce381/pyScss-1.3.4.tar.gz (120 kB)
INFO:kolla.common.utils.horizon: ERROR: Command errored out with exit status 1:
INFO:kolla.common.utils.horizon: command: /var/lib/kolla/venv/bin/python -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-rr0db3qs/pyScss/setup.py'"'"'; __file__='"'"'/tmp/pip-install-rr0db3qs/pyScss/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-install-rr0db3qs/pyScss/pip-egg-info
INFO:kolla.common.utils.horizon: cwd: /tmp/pip-install-rr0db3qs/pyScss/
INFO:kolla.common.utils.horizon: Complete output (5 lines):
INFO:kolla.common.utils.horizon: Traceback (most recent call last):
INFO:kolla.common.utils.horizon: File "<string>", line 1, in <module>
INFO:kolla.common.utils.horizon: File "/tmp/pip-install-rr0db3qs/pyScss/setup.py", line 9, in <module>
INFO:kolla.common.utils.horizon: from setuptools import setup, Extension, Feature
INFO:kolla.common.utils.horizon: ImportError: cannot import name 'Feature'

Devstack also has the same problem.

Are there any plans to fix it?

pyscss project got issue: https://github.com/Kronuz/pyScss/issues/385

What are plans of Horizon team?

[Marcin Juszkiewicz (hrw)]

https://review.opendev.org/711930 workarounds the problem by blocking setuptools 46.0.0 from being installed.

Will hurt anyway on any newer setuptools version so it needs to be fixed in horizon.

[Radosław Piliszek (yoctozepto)]

devstack master is safe because of gr removal of bad setuptools here: https://review.opendev.org/711930

other py3-enabled branches are still affected (as commented on change)

[Marcin Juszkiewicz (hrw)]

Problem still present in Kolla as setuptools 46 is installed by virtualenv.

Will look at options.

[lina He (linahe)]

Hi,

I failed to install a stable/stein horizon on ubuntu because of this bug. I saw some patchsets merged to ussuri and train to solve this issue. I would like to know whether there is a plan to fix this issue for stein and other versions.

[Marcin Juszkiewicz (hrw)]

Ussuri got it fixed with PyScss 1.3.6 release (and later update to 1.3.7).

Train, Stein are in progress.

[lina He (linahe)]

Thanks for your quick reply.

[Dr. Jens Harbott (j-harbott)]

AFAICT this doesn't affect devstack directly, please add steps to reproduce if the issue still exists.

[Akihiro Motoki (amotoki)]

horizon has fixed the issue but unfortunately the fixes are not linked with it. I am summarizing the fixes.
Multiple fixes are involved in the master branch (i.e. ussuri), so fixes in the stable/train branch would be better for the summary.

The related fixes in stable/train are as follows:
- 9813577f7d0137da0e29c7630cffc3e1e1b329f5 (Update pyScss to 1.3.7)
- f26c88721614d1c25bcd26740b8fb20a7a97bd05 (Implement 'selector-append' sass function) which fixes an problem in the material design with pyScss 1.3.5 or later.

They were backported to stable/stein too.

Regarding stable/rocky or older branches, we don't backport them from the following reasons:
- The CI jobs are not broken as they use setuptools<46.
- It is better to avoid requirements change as much as possible.
- stable/rocky and older branches are in the extended maintenance phase so the upstream development team does not focus on them much.