[BUG] pip install ./path/to/package requires the network

setuptools version

setuptools-65.6.3

Python version

Python 3.10

OS

Ubuntu

Additional environment information

No network connectivity, e.g.

• Developer on a long flight
• Developer located in the middle of the Amazon forest
• Developer located in a deep cave
• Developer located in a nuclear submarine

Description

Running python ./path/to/package/setup.py install raises a warning:

SetuptoolsDeprecationWarning: setup.py install is deprecated. Use build and pip and other standards-based tools.

however, pip install ./path/to/package requires access to the network in order to work, even if all the dependencies are available locally. This means that it's impossible to hack on your favourite C extension if the network is not available.

Expected behavior

See above.

How to Reproduce

With the network available. Note that all the build dependencies are available:

$ git clone git@github.com:psycopg/psycopg.git
$ cd psycopg
$ pip install -v ./psycopg_c/
Using pip 22.3.1 from /home/piro/dev/psycopg3/.venv/lib/python3.10/site-packages/pip (python 3.10)
Processing ./psycopg_c
  Running command pip subprocess to install build dependencies
  Collecting setuptools>=49.2.0
    Using cached setuptools-65.6.3-py3-none-any.whl (1.2 MB)
  Collecting wheel>=0.37
    Using cached wheel-0.38.4-py3-none-any.whl (36 kB)
  Collecting Cython>=3.0.0a11
    Using cached Cython-3.0.0a11-cp310-cp310-manylinux_2_17_x86_64.manylinux2014_x86_64.manylinux_2_28_x86_64.whl (2.6 MB)
  Installing collected packages: wheel, setuptools, Cython
  Successfully installed Cython-3.0.0a11 setuptools-65.6.3 wheel-0.38.4
  Installing build dependencies ... done
  Running command Getting requirements to build wheel
  Getting requirements to build wheel ... done
  Running command Preparing metadata (pyproject.toml)
  running dist_info
...
Successfully built psycopg-c
Installing collected packages: psycopg-c
Successfully installed psycopg-c-3.1.8.dev1

Taking down the network:

$ pip install -v ./psycopg_c/
Using pip 22.3.1 from /home/piro/dev/psycopg3/.venv/lib/python3.10/site-packages/pip (python 3.10)
Processing ./psycopg_c
  Running command pip subprocess to install build dependencies
  WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.HTTPSConnection object at 0x7f45501461d0>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution')': /simple/setuptools/
  WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.HTTPSConnection object at 0x7f45501464d0>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution')': /simple/setuptools/
^C  Installing build dependencies ... canceled

setup.py install works instead:

$ python ./psycopg_c/setup.py install
/home/piro/dev/psycopg3/.venv/lib/python3.10/site-packages/setuptools/installer.py:27: SetuptoolsDeprecationWarning: setuptools.installer is deprecated. Requirements should be satisfied by a PEP 517 installer.
  warnings.warn(
running install
/home/piro/dev/psycopg3/.venv/lib/python3.10/site-packages/setuptools/command/install.py:34: SetuptoolsDeprecationWarning: setup.py install is deprecated. Use build and pip and other standards-based tools.
  warnings.warn(
/home/piro/dev/psycopg3/.venv/lib/python3.10/site-packages/setuptools/command/easy_install.py:158: EasyInstallDeprecationWarning: easy_install command is deprecated. Use build and pip and other standards-based tools.
  warnings.warn(
running bdist_egg
running egg_info
writing psycopg_c.egg-info/PKG-INFO
writing dependency_links to psycopg_c.egg-info/dependency_links.txt
writing top-level names to psycopg_c.egg-info/top_level.txt
reading manifest file 'psycopg_c.egg-info/SOURCES.txt'
adding license file 'LICENSE.txt'
writing manifest file 'psycopg_c.egg-info/SOURCES.txt'
installing library code to build/bdist.linux-x86_64/egg
running install_lib
running build_py
running build_ext
building 'psycopg_c._psycopg' extension
...

Installed /home/piro/dev/psycopg3/.venv/lib/python3.10/site-packages/psycopg_c-3.1.8.dev1-py3.10-linux-x86_64.egg
Processing dependencies for psycopg-c==3.1.8.dev1
Finished processing dependencies for psycopg-c==3.1.8.dev1

Output

See above.

Start by reproducing pip install -v ./psycopg_c/ with the network unavailable and compare it with python ./psycopg_c/setup.py install. Read the build-dependency handling around the pyproject.toml build step; done means a local package installs successfully offline when its dependencies are already available.