pyproject.toml-based builds lose proxy config for build-dependency installation #6018
Description
Environment
- pip version: 18.1
- Python version: 3.7.1
- OS: MacOS, Windows
Description
When behind a proxy, installing a project with a pyproject.toml defining a build-system.requires option will fail, because the BuildEnvironment.install_requirements() implementation runs pip as a child process without copying across proxy configuration.
Expected behavior
Even in an isolated build environment, proxy access needs to be configured, so that build dependencies can be downloaded.
How to Reproduce
Block direct access to PyPI, and use a proxy to install pyinstaller, e.g. pip install pyinstaller --proxy=http://webdefence.global.blackspider.com:80 --trusted-host=pypi.python.org.
Disabling build isolation with --no-build-isolation and manually installing the build requirements first lets you work around this issue.
Output
$ pip install pyinstaller --proxy=http://webdefence.global.blackspider.com:80 --trusted-host=pypi.python.org
Collecting pyinstaller
Using cached https://files.pythonhosted.org/packages/03/32/0e0de593f129bf1d1e77eed562496d154ef4460fd5cecfd78612ef39a0cc/PyInstaller-3.4.tar.gz
Installing build dependencies ... error
Complete output from command c:\users\blaggr\appdata\local\programs\python\python37-32\scripts\python.exe -m pip install --ignore-installed --no-user --prefix C:\Users\blaggr\AppData\Local\Temp\pip-build-env-vd3w15r1 --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple --trusted-host pypi.python.org -- setuptools wheel:
Collecting setuptools
Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)")': /simple/setuptools/
Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)")': /simple/setuptools/
Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)")': /simple/setuptools/
Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)")': /simple/setuptools/
Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='pypi.org', port=443): Read timed out. (read timeout=15)")': /simple/setuptools/
Could not find a version that satisfies the requirement setuptools (from versions: )
No matching distribution found for setuptoolsI'm filing this ticket as a follow-up to a Stack Overflow question, where a Windows user ran into this problem. They shared their pip -vvv output to help diagnosing.