Upgrade vendored pep517 to 0.10.0 or later

[paugier]

Each time I submit an issue here (pip), I'm getting not very nice feedback, but let's try again 🙂

If a build uses import colorlog (to get https://pypi.org/project/colorlog/), the module imported is pip/_vendor/pep517/colorlog.py, which is incompatible with https://pypi.org/project/colorlog/ and one gets an error like:

AttributeError: module 'colorlog' has no attribute 'StreamHandler'

[pfmoore]

Can you provide a small, self-contained example of this? It sounds like a bug if setup.py is able to see parts of pip's vendored modules, but it's difficult to be sure without a test case we can run.

[pfmoore]

By the way,

Each time I submit an issue here (pip), I'm getting not very nice feedback

I'm sorry if that's happened to you, it certainly shouldn't. I checked the issues that I could find which you've raised and couldn't see what you were referring to. Could you give an example? I would certainly hope that if you're taking the time to help us by raising issues, we'd respond positively. (That doesn't necessarily mean that we'd agree with every suggestion, but I'd hope the discussion would at least be civil...)

[paugier]

• setup.py

from setuptools import setup
import colorlog as logging
handler = logging.StreamHandler()
setup()

• pyproject.toml

[build-system]
requires = ["setuptools", "wheel", "colorlog"]
build-backend = "setuptools.build_meta"

Sorry for the first sentence of my issue. I'm tired with different things (not about pip) and that's true that the recent evolutions of pip / pyproject.toml, pep517, pep518 lead to real difficulties for me. I'm loosing a lot of time and I can't manage to find good solutions to my applications. Anyway, that's not the subject of this issue and I realize that it's for the good of most Python users.

[pfmoore]

Sorry for the first sentence of my issue.

No worries, there's a lot of change at the moment and it's hard for all of us - I could easily imagine one of us giving you a reply somewhere that translated to "aaargh, we're trying to do our best, stop coming up with more problems!!" so I wanted to make sure that wasn't what had happened 🙂

I just tried out your test case and can confirm that I see the bug. Thanks for a nice easy example to test with! I tried with both py -m pip wheel . and py -m pip wheel --use-pep517 . and both failed the same way.

I don't know much about pip's vendoring code, so I'll need to do some digging before I can work out what's going on, but I can confirm that this is not correct behaviour.

[duckinator]

TL;DR: It appears to be a sys.path ordering problem. If you specify a build-system dependency where the name is the same as any file in the vendored copy of pep517, you'll have this problem.

---

Long version:

1. Using setup.py-1 (see below), I found sys.path (see below)
2. My venv did not contain colorlog, and it wasn't installed globally, so that means it's likely in /tmp.
3. I used setup.py-2 (see below) to let me look into /tmp before pip cleaned up after itself, by running find /tmp -name colorlogs.
4. This confirmed my suspicion that it is in /tmp — specifically (for me) /tmp/pip-build-env-*/overlay/lib/python3.7/site-packages/colorlog
5. The path lists pip/_vendor/pep517 first.

The end result of this is that if anyone's build relies on a library with the name of any files in the vendored copy of the pep517 library, they'll encounter this same problem.

---

Here's the path I discovered in step 1, with some extra newlines so it's actually readable:

['/home/puppy/dev/python/duckinator/pip-8887/venv/lib/python3.7/site-packages/pip/_vendor/pep517',
'/tmp/pip-build-env-j0p_lx6e/site',
'/usr/lib64/python37.zip',
'/usr/lib64/python3.7',
'/usr/lib64/python3.7/lib-dynload',
'/tmp/pip-build-env-j0p_lx6e/overlay/lib/python3.7/site-packages',
'/tmp/pip-build-env-j0p_lx6e/overlay/lib64/python3.7/site-packages',
'/tmp/pip-build-env-j0p_lx6e/normal/lib/python3.7/site-packages',
'/tmp/pip-build-env-j0p_lx6e/normal/lib64/python3.7/site-packages']

Here's the setup.py variants mentioned above:

setup.py-1 (prints path)

from setuptools import setup
import colorlog as logging
import sys
print(sys.path)
handler = logging.StreamHandler()
setup()

setup.py-2 (sleeps 1,000 seconds)

from setuptools import setup
import colorlog as logging
import time
time.sleep(1000)
handler = logging.StreamHandler()
setup()

[duckinator]

A single simplified setup.py which demonstrates everything I said above:

from pathlib import Path

print(list(Path('/tmp').glob('pip-build-env-*/**/colorlog'))[0])

# All of these are from pep517.
# The commented-out ones all fail because the modules get imported, but raise an exception.
import _in_process
# import build
# import check
import colorlog
import compat
import dirtools
# import envbuild
# import meta
# import wrappers

print(_in_process)
print(colorlog)
print(compat)
print(dirtools)

exit(1)

The results of running this:

  ERROR: Command errored out with exit status 1:
   command: /home/puppy/dev/python/duckinator/pip-8887/venv/bin/python3 /home/puppy/dev/python/duckinator/pip-8887/venv/lib64/python3.7/site-packages/pip/_vendor/pep517/_in_process.py get_requires_for_build_wheel /tmp/tmpobia7xyo
       cwd: /tmp/pip-req-build-0idiwuz8
  Complete output (5 lines):
  /tmp/pip-build-env-p8raq723/overlay/lib/python3.7/site-packages/colorlog
  <module '_in_process' from '/home/puppy/dev/python/duckinator/pip-8887/venv/lib/python3.7/site-packages/pip/_vendor/pep517/_in_process.py'>
  <module 'colorlog' from '/home/puppy/dev/python/duckinator/pip-8887/venv/lib/python3.7/site-packages/pip/_vendor/pep517/colorlog.py'>
  <module 'compat' from '/home/puppy/dev/python/duckinator/pip-8887/venv/lib/python3.7/site-packages/pip/_vendor/pep517/compat.py'>
  <module 'dirtools' from '/home/puppy/dev/python/duckinator/pip-8887/venv/lib/python3.7/site-packages/pip/_vendor/pep517/dirtools.py'>
  ----------------------------------------

[uranusjr]

It seems to me the best solution would be for pep517 to put its in-process stuff in a subdirectory, so components in the pep517 module do not pollute sys.path. Should we move this issue to the pep517 repository?

[duckinator]

@uranusjr yeah, that would probably make sense.

[hexagonrecursion]

I want to work on this bug.

[uranusjr]

Tou will need to send issues and pull requests to this repository instead: https://github.com/pypa/pep517

[hexagonrecursion]

I was confused why out of the dozens of libraries pip vendors only pep517 is in the path. I was thinking maybe pep517 is not vendored correctly. bcc execsnoop cleared that up:

PCOMM            PID    PPID   RET ARGS
pip              21719  18141    0 /home/user/.conda/envs/hello/bin/pip install -e ./hello-setup/
uname            21721  21719    0 /usr/bin/uname -rs
python           21722  21719    0 /home/user/.conda/envs/hello/bin/python /home/user/pip/src/pip install --ignore-installed --no-user --prefix /tmp/pip-build-env-xmo5gc8z/overlay --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- setuptools wheel colorlog
uname            21726  21722    0 /usr/bin/uname -rs
python           21727  21719    0 /home/user/.conda/envs/hello/bin/python /home/user/pip/src/pip/_vendor/pep517/_in_process.py get_requires_for_build_wheel /tmp/tmp1trhhp23

Note the last line: pip runs src/pip/_vendor/pep517/_in_process.py as a subprocess. This is why its parent directory is in the path.

[uranusjr]

Please continue the discussion in pypa/pep517. It will raise awareness to people working on the library.

[hexagonrecursion]

This should be closed in favor of pypa/pyproject-hooks#104