将 Poetry 与 PyEnv 结合使用并遇到 Python 版本问题

Question

I'm working on WSL2 Ubuntu. I've been taking a course in backend API development using Fastapi. My Ubuntu default python is 3.8 I believe. I'm trying to use python 3.10.0 for my development. I've done the following:

1. pyenv install 3.10.0
2. cd to my project folder and pyenv local 3.10.0 (creates.python-version file containing 3.10.0)
3. poetry shell (this creates a.venv folder and all dependencies are added there during development). Bash Prompt has (.venv) in it.
4. python --version shows 3.10.0 as current version

My problem is that when I look into the.venv/bin file, all of the symbolic links show python 3.8.

drwxr-xr-x 2 mryan mryan 4096 Feb  1 23:12 .
drwxr-xr-x 4 mryan mryan 4096 Feb  1 23:12 ..
-rw-r--r-- 1 mryan mryan 2152 Feb  1 23:12 activate
-rw-r--r-- 1 mryan mryan 1444 Feb  1 23:12 activate.csh
-rw-r--r-- 1 mryan mryan 3033 Feb  1 23:12 activate.fish
-rw-r--r-- 1 mryan mryan 1303 Feb  1 23:12 activate.nu
-rw-r--r-- 1 mryan mryan 1754 Feb  1 23:12 activate.ps1
-rw-r--r-- 1 mryan mryan 1199 Feb  1 23:12 activate_this.py
-rw-r--r-- 1 mryan mryan  333 Feb  1 23:12 deactivate.nu
-rwxr-xr-x 1 mryan mryan  249 Feb  1 23:12 pip
-rwxr-xr-x 1 mryan mryan  249 Feb  1 23:12 pip-3.8
-rwxr-xr-x 1 mryan mryan  249 Feb  1 23:12 pip3
-rwxr-xr-x 1 mryan mryan  249 Feb  1 23:12 pip3.8
lrwxrwxrwx 1 mryan mryan   18 Feb  1 23:12 python -> /usr/bin/python3.8
lrwxrwxrwx 1 mryan mryan    6 Feb  1 23:12 python3 -> python
lrwxrwxrwx 1 mryan mryan    6 Feb  1 23:12 python3.8 -> python
-rwxr-xr-x 1 mryan mryan  236 Feb  1 23:12 wheel
-rwxr-xr-x 1 mryan mryan  236 Feb  1 23:12 wheel-3.8
-rwxr-xr-x 1 mryan mryan  236 Feb  1 23:12 wheel3
-rwxr-xr-x 1 mryan mryan  236 Feb  1 23:12 wheel3.8

When I try using the command poetry env use 3.10.0 I get the following:

(.venv) mryan ~/python/fastapi1/.venv/bin $poetry env use 3.10.0
/bin/sh: 1: python3.10: not found

  EnvCommandError

  Command python3.10 -c "import sys; print('.'.join([str(s) for s in sys.version_info[:3]]))" errored with the following return code 127, and output:


  at ~/.local/share/pypoetry/venv/lib/python3.8/site-packages/poetry/utils/env.py:378 in activate
       374│                     shell=True,
       375│                 )
       376│             )
       377│         except CalledProcessError as e:
    →  378│             raise EnvCommandError(e)
       379│
       380│         python_version = Version.parse(python_version.strip())
       381│         minor = "{}.{}".format(python_version.major, python_version.minor)
       382│         patch = python_version.text
(.venv) mryan ~/python/fastapi1/.venv/bin $python3.10
python3.10: command not found

What am I doing wrong here? I feel I'm missing something significant here. I've been through a zillion web pages on poetry and virtual environments.

Answer 1

I had the same problem you are having, I used to be able to use:

pyenv local 3.10.0

poetry new example-project

And poetry would create example-project with a venv in it based on python 3.10.0. This no longer worked for me so I found that these commands did work for me:

poetry new example-project
cd example-project/
poetry env use 3.10.0
poetry update

In case your project already had a venv installed it might be a good idea to remove that first before using the poetry env command. I'm pretty sure you haven't added pyenv to your PATH properly. Check out the installation instructions for pyenv , specifically the ' Configure your shell's environment for Pyenv' section.

Answer 2

I am surprised that poetry shell creates .venv . Are you certain about that? Or did you maybe create it with virtualenv ?

I just kind of replicated what you probably did and did not get the error. I would recommend you to create a minimal, reproducible example . Then you will probably catch what is wrong. For this I case I recommend creating a bash script. A start could be:

mkdir ~/python/test_error
cd ~/python/test_error
cp ~/python/fastapi1/pyproject.toml .
pyenv local 3.10.0
poetry env use 3.10.0

This script works for me (when I change the folders).

Answer 3

I'm able to replicate your exact error using these commands:

poetry new test-project

cd test-project/

poetry env use 3.10

Result in the exact same error you are getting. However, this works for me:

poetry new test-project

cd test-project/

pyenv local 3.10

poetry env use 3.10

Following these commands my poetry will create a .venv inside the project's folder successfully. By the way, you'll have to edit the pyproject.toml file manually, because that doesn't change using this method.

If this doesn't work I suspect something went wrong while adding pyenv to your PATH . In that case you could try resetting your 'dot-files' ( .bashrc , .bash_profile and/or .profile ) and add pyenv again using these commands from the pyenv github :

# the sed invocation inserts the lines at the start of the file
# after any initial comment lines
sed -Ei -e '/^([^#]|$)/ {a \
export PYENV_ROOT="$HOME/.pyenv"
a \
export PATH="$PYENV_ROOT/bin:$PATH"
a \
' -e ':a' -e '$!{n;ba};}' ~/.profile
echo 'eval "$(pyenv init --path)"' >>~/.profile

echo 'eval "$(pyenv init -)"' >> ~/.bashrc

Answer 4

Thanks SWHJ, I also come up with that solution. Just a small point here is we need need to set this config

poetry config settings.virtualenvs.in-project true

so poetry will create a.venv inside the project's folder