poetry: Installing packages in a python 3.6 environment fail due to PEP 517

• I am on the latest Poetry version.

• I have searched the issues of this repo and believe that this is not a duplicate.

• If an exception occurs when executing a command, I executed it again in debug mode (-vvv option).

• OS version and name: Ubuntu 22.0.1

• Poetry version: 1.2.0

• Link of a Gist with the contents of your pyproject.toml file: pyproject.toml

Issue

A dependency uses MarkupSafe and our project must support python ^3.6.2. Since I updated to poetry 1.2.0, I can not use the python 3.6 environment anymore.

Installing MarkupSafe manually works, when I disable pep 517:

> poetry run python -m pip install --no-use-pep517 markupSafe==2.0.1

However, there is no option to disable pep 517 in poetry. Is there any other way to install such packages?

Errors

> poetry env use 3.6
> poetry -vvv install
Using virtualenv: /tmp/foo/.venv
Project environment contains an empty path in sys_path, ignoring.
Installing dependencies from lock file

Finding the necessary packages for the current system

Package operations: 1 install, 0 updates, 0 removals

  • Installing markupsafe (2.0.1): Pending...
Creating new session for pypi.org
  • Installing markupsafe (2.0.1): Installing...
  • Installing markupsafe (2.0.1): Failed

  Stack trace:

  2  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/utils/env.py:1469 in _run
      1467│                 )
      1468│             else:
    → 1469│                 output = subprocess.check_output(
      1470│                     command, stderr=subprocess.STDOUT, env=env, **kwargs
      1471│                 )

  1  /usr/lib/python3.10/subprocess.py:420 in check_output
       418│         kwargs['input'] = empty
       419│ 
    →  420│     return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
       421│                **kwargs).stdout
       422│ 

  CalledProcessError

  Command '['/tmp/foo/.venv/bin/python', '/home/john/.local/share/pypoetry/venv/lib/python3.10/site-packages/virtualenv/seed/wheels/embed/pip-21.3.1-py3-none-any.whl/pip', 'install', '--use-pep517', '--disable-pip-version-check', '--prefix', '/tmp/foo/.venv', '--no-deps', '/home/local/.cache/pypoetry/artifacts/09/a9/a6/7e309619221c03e9a693897779a3fa9b06b4c71edb005b6919654585d3/MarkupSafe-2.0.1.tar.gz']' returned non-zero exit status 1.

  at /usr/lib/python3.10/subprocess.py:524 in run
       520│             # We don't call process.wait() as .__exit__ does that for us.
       521│             raise
       522│         retcode = process.poll()
       523│         if check and retcode:
    →  524│             raise CalledProcessError(retcode, process.args,
       525│                                      output=stdout, stderr=stderr)
       526│     return CompletedProcess(process.args, retcode, stdout, stderr)
       527│ 
       528│ 

The following error occurred when trying to handle this error:


  Stack trace:

  3  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/utils/pip.py:49 in pip_install
       47│ 
       48│     try:
    →  49│         return environment.run_pip(*args)
       50│     except EnvCommandError as e:
       51│         raise PoetryException(f"Failed to install {path.as_posix()}") from e

  2  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/utils/env.py:1433 in run_pip
      1431│         cmd = pip + list(args)
      1432│ 
    → 1433│         return self._run(cmd, **kwargs)
      1434│ 
      1435│     def run_python_script(self, content: str, **kwargs: Any) -> int | str:

  1  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/utils/env.py:1722 in _run
      1720│     def _run(self, cmd: list[str], **kwargs: Any) -> int | str:
      1721│         kwargs["env"] = self.get_temp_environ(environ=kwargs.get("env"))
    → 1722│         return super()._run(cmd, **kwargs)
      1723│ 
      1724│     def get_temp_environ(

  EnvCommandError

  Command ['/tmp/foo/.venv/bin/python', '/home/local/.local/share/pypoetry/venv/lib/python3.10/site-packages/virtualenv/seed/wheels/embed/pip-21.3.1-py3-none-any.whl/pip', 'install', '--use-pep517', '--disable-pip-version-check', '--prefix', '/tmp/foo/.venv', '--no-deps', '/home/local/.cache/pypoetry/artifacts/09/a9/a6/7e309619221c03e9a693897779a3fa9b06b4c71edb005b6919654585d3/MarkupSafe-2.0.1.tar.gz'] errored with the following return code 1, and output: 
  Looking in indexes: https://pypi.org/simple, 
  Processing /home/local/.cache/pypoetry/artifacts/09/a9/a6/7e309619221c03e9a693897779a3fa9b06b4c71edb005b6919654585d3/MarkupSafe-2.0.1.tar.gz
    Installing build dependencies: started
    Installing build dependencies: finished with status 'done'
    Getting requirements to build wheel: started
    Getting requirements to build wheel: finished with status 'error'
    ERROR: Command errored out with exit status 1:
     command: /tmp/foo/.venv/bin/python /home/local/.local/share/pypoetry/venv/lib/python3.10/site-packages/virtualenv/seed/wheels/embed/pip-21.3.1-py3-none-any.whl/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /tmp/tmpkvyouqoq
         cwd: /tmp/pip-req-build-80e95xhl
    Complete output (1 lines):
    /tmp/foo/.venv/bin/python: can't find '__main__' module in '/home/local/.local/share/pypoetry/venv/lib/python3.10/site-packages/virtualenv/seed/wheels/embed/pip-21.3.1-py3-none-any.whl/pip/_vendor/pep517/in_process/_in_process.py'
    ----------------------------------------
  WARNING: Discarding file:///home/local/.cache/pypoetry/artifacts/09/a9/a6/7e309619221c03e9a693897779a3fa9b06b4c71edb005b6919654585d3/MarkupSafe-2.0.1.tar.gz. Command errored out with exit status 1: /tmp/foo/.venv/bin/python /home/local/.local/share/pypoetry/venv/lib/python3.10/site-packages/virtualenv/seed/wheels/embed/pip-21.3.1-py3-none-any.whl/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /tmp/tmpkvyouqoq Check the logs for full command output.
  ERROR: Command errored out with exit status 1: /tmp/foo/.venv/bin/python /home/local/.local/share/pypoetry/venv/lib/python3.10/site-packages/virtualenv/seed/wheels/embed/pip-21.3.1-py3-none-any.whl/pip/_vendor/pep517/in_process/_in_process.py get_requires_for_build_wheel /tmp/tmpkvyouqoq Check the logs for full command output.
  

  at ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/utils/env.py:1473 in _run
      1469│                 output = subprocess.check_output(
      1470│                     command, stderr=subprocess.STDOUT, env=env, **kwargs
      1471│                 )
      1472│         except CalledProcessError as e:
    → 1473│             raise EnvCommandError(e, input=input_)
      1474│ 
      1475│         return decode(output)
      1476│ 
      1477│     def execute(self, bin: str, *args: str, **kwargs: Any) -> int:

The following error occurred when trying to handle this error:


  Stack trace:

  5  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/installation/executor.py:250 in _execute_operation
      248│ 
      249│             try:
    → 250│                 result = self._do_execute_operation(operation)
      251│             except EnvCommandError as e:
      252│                 if e.e.returncode == -2:

  4  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/installation/executor.py:323 in _do_execute_operation
      321│             return 0
      322│ 
    → 323│         result: int = getattr(self, f"_execute_{method}")(operation)
      324│ 
      325│         if result != 0:

  3  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/installation/executor.py:443 in _execute_install
      441│ 
      442│     def _execute_install(self, operation: Install | Update) -> int:
    → 443│         status_code = self._install(operation)
      444│ 
      445│         self._save_url_reference(operation)

  2  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/installation/executor.py:485 in _install
      483│         )
      484│         self._write(operation, message)
    → 485│         return self.pip_install(archive, upgrade=operation.job_type == "update")
      486│ 
      487│     def _update(self, operation: Install | Update) -> int:

  1  ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/installation/executor.py:120 in pip_install
      118│     ) -> int:
      119│         try:
    → 120│             pip_install(req, self._env, upgrade=upgrade, editable=editable)
      121│         except EnvCommandError as e:
      122│             output = decode(e.e.output)

  PoetryException

  Failed to install /home/local/.cache/pypoetry/artifacts/09/a9/a6/7e309619221c03e9a693897779a3fa9b06b4c71edb005b6919654585d3/MarkupSafe-2.0.1.tar.gz

  at ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/utils/pip.py:51 in pip_install
       47│ 
       48│     try:
       49│         return environment.run_pip(*args)
       50│     except EnvCommandError as e:
    →  51│         raise PoetryException(f"Failed to install {path.as_posix()}") from e
       52│