venvwrap 0.1

A collection of bash functions for venv management

venvwrap

A collection of bash functions for python venv mangement

Install

via pip

pip install venvwrap
source bin/venvwrap.sh

via github

git clone https://github.com/hunkeydee/venvwrap
sha256sum -c venvwrap/sha256
source venvwrap/venvwrap.sh

Asciicast Demos

• basic create, pip-install, use, destroy
• create venvs from varied python versions
• link packages between venvs

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Bash Environment and File System effects

• The script exports the following variables and default values. Change them as needed before installation.

  • VENV_HOME="${HOME}"/.venvs -> Default folder for venv directories

  • VENV_PY=$(which python3) -> Default python installation

• If the $VENV_HOME directory does not already exist on the file system, this script will create it.

• All venvwrap commands are bash functions, with a small reliance on common binaries (rm and ln).

Usage

venvmk - Create venv(s), installs pip, wheel, setuptools

usage: venvmk <venv>...

  ex: `venvmk alpha` -> creates a venv called 'alpha'
  ex: `venvmk bravo charlie` -> creates two seperate venvs
  ex: `venvmk delta -p /opt/bin/python3.6\` -> create venv using alt python

venvrm - Delete venv(s)

usage: venvrm <venv>...

  ex: `venvrm delta` -> deletes the venv called 'delta'
  ex: `venvrm echo foxtrot` deletes two venvs

workon - Enter/activate a venv

  usage: workon <venv>

  ex: `workon golf` -> activates the 'golf' venv context

venvex - Exit/deactivate the current venv

  usage: venvex

  ex: `venvex` -> deactivates the current venv

venvls - List all virtual environments managed by venvwrap

  usage: venvls

  ex `venvls` -> returns a dir listing of $VENV_HOME

venvpkgls - List packages installed or linked in venv(s)

  usage: venvpkgls <venv>...

  ex: `venvpkgls juliet` -> runs pip list for 'juliet', then displays link in the site-packages directory

venvcmd - Run cmd in venv

  usage: venvcmd <venv> <cmd>

  ex: `venvcmd kilo python3 ./server.py` -> runs server.py in 'kilo' venv.  note that in this case ./server.py would need to be placed at ~/.venvs/kilo/server.py.

venvinstall - Install pip package(s) in venv

  usage: venvinstall <venv> <pkg>...'

  ex: `venvinstall mike urllib3` -> installs urllib3 in 'mike'
  ex: `venvinstall november numpy chardet` -> installs numpy and chardet

venvlink - link a package from source venv> to target venv

  usage: venvlink <source_venv> <source_pkg> <target_venv>

  ex: venvlink oscar matplotlib papa` -> creates a link in 'papa' pointing to the matplotlib package in oscar

Background

I didn't know enough about venvs (or bash scripting), so I spent a weekend learning/making this project. Its generally inspired by virtualenvwrapper. Instead of wrapping virtualenv, these functions support the built-in python venv. I think you can use virtualenvwrapper to wrap venvs since they're almost equivilent, but just using someone elses code means I learn less.

The main feature I wanted to add while making this script was to have the ability to link packages between virtual environments. Imagine you have a need to setup three seperate venvs, but they all need the same numpy. You could install numpy in all three, but that wastes time, filespace and bandwidth. venvlink works around this by placing link files in the site-packages dir to the installed packages of other venvs. For example, venvlink alpha numpy bravo would take the numpy package already installed in alpha, and make a link file to it within bravo's site-packages. This lets me set up a flexible development environment without duplicating lots of files.

Very little effort was put into testing against other linux systems. It works for me with bash 5.0.3 running on Debian Buster as well as Windows 10 wsl. I tested python mangement with python3.7.3 directly from debian apt packages, as well as python3.6.10, python3.7.7, and python3.8.3 compiled directly from python.org. All currently supported versions of python (May 2020) tested successful.

Some dependencies include:

python	other cmds
python3	bash
python3-venv	rm ln
python3-pip