Pyenv choose virtualenv directory - python-3.x

Question

I just began to use pyenv to manage my python versions, and began to use the pyenv virtualenv plugin to manage my virtualenvs, and so far, I have loved it. One thing I miss however, is that with virtualenv, you could actually place virtual environments in repository directories so that your repository was a completely reproducible environment. Does anyone know of a way to choose the directory of your virtualenv in pyenv?

Answer 1

Short answer: You can’t, as far as I know.
It wouldn’t really work either, right? If you use pyenv virtualenv to install a virtualenv into a repo, and you clone that repo to another machine… how would pyenv on the new machine know to take control of the virtualenv in the repository?
Also, “you probably shouldn’t do that”. Virtualenvs are not 100% decoupled from the underlying Python installation, and aren’t really all that portable. And do you really want to litter your repositories with a bunch of easily replicated junk? The “right” way to go about things is probably to to maintain a requirements.txt for pip — that way you can easily reproduce your development environment wherever you clone your repo.
That all said, there’s nothing stopping you from using plain old virtualenv to create a virtualenv anywhere you like, even if you installed virtualenv into a Python interpreter under pyenv control. That virtualenv itself will of course not be administered by pyenv, but you can still use it as you always did…

Answer 2

Here is a GitHub issue on the project tracker asking about this: https://github.com/pyenv/pyenv/issues/802
The reply by a project collaborator was:
You can just create virtualenv in any location. To use it from pyenv, create symlink to the environment in ~/.pyenv/versions
although I must say I'm not very satisfied with this solution.

Answer 3

There's a workaround
In your project directory, create a .python-version file. Assuming you already installed some virtual environment using pyenv-virtualenv, then append this line to it(you may want to change the version number):
3.7.1/envs/your-project-name#3.7.1
Whenever you enter into the directory, the correct python version will be used, and it works pretty well.

Answer 4

How about:
pyenv install -s 3.8.3 # install preferred version if needed
PYENV_VERSION=3.8.3 python -m venv /tmp/your/prefered/dir ; source /tmp/your/prefered/dir/activate
Note that this method uses venv, not virtualenv, which is slightly different, but a part of a standard library.

Answer 5

Slightly left-field answer, but I ended up writing a hacky equivalent of pyenv that looks for a virtualenv in a directory and its parents because pyenv doesn't really seem to support this as layed out in the answer about.
I called this script enpy, put it on my path and then called e.g. enpy -c import sys; print(sys.executable)
#!/usr/bin/python3
import os
import sys
from pathlib import Path
NAMES = ("venv", "env", ".env", ".venv")
def find_python():
cwd = Path(os.getcwd())
for direc in [cwd] + list(cwd.parents):
for p in NAMES:
venv = direc / p
if venv.exists():
return venv / "bin" / "python"
else:
raise Exception("Could not find python")
python = find_python()
os.execvp(str(python), [str(python)] + sys.argv[1:])

Answer 6

To build on-top of a previous comment, you can add this to your .zshrc:
pyCreate () {
if [ -d .venv ];then
rm -rf .venv; fi &&
if [ -f .python-version ];then
pyVersion="local"
else
pyVersion="global"; fi &&
location=${1:-requirements.txt} &&
if [ -f $location ];then
action=(pip install -r $location)
else
action=(echo "\n No file: $location \n"); fi &&
PYENV_VERSION=`pyenv $pyVersion` python -m venv .venv &&
source .venv/bin/activate &&
pip install --upgrade pip && $action
}

Answer 7

I use the simple recipe of
python -m venv virt to create the local venv
Link the venv to pyenv with ln -s <local virt> ~/.pyenv/versions/<venv name>
Now you can do pyenv local <venv name> and all other normal operations from pyenv with this venv.
For the interested I have made two CLIs
pyenv-here to create a new venv and set local dir in one go
pyenv-link to link a local virt to pyenv

Answer 8

The top comment is wrong; you certainly can.
Once you create your virtual environment with pyenv virtualenv 3.9.15 your-environment-name, you can specify the directories in which this environment will be used automatically with the following command. In your desired directory, run:
pyenv local your-environment-name
The command will create the necessary .python-version file that includes the name of your environment. From now on, every time you enter the folder, the specified environment will be used.

Answer 9

If you want to just use pyenv specific python version and create virtual env from it in wanted directory, you can for example do this:
~/.pyenv/versions/3.10.8/bin/python -m venv my/path/to/venv