viv isn't venv

Documentation

Try before you buy!

python3 <(curl -fsSL viv.dayl.in/viv.py) run pycowsay -- "viv isn't venv\!"

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Viv is a standalone dependency-free venv creator ¹. Viv helps you ignore silly things like managing temporary or rarely used virtual environments, while still unleashing the full power of Python scripting with its entire ecosystem at your disposal.

Viv's uncompromising insistence on portability means that it will always:

1. only use the standard library
2. never exceed a single script.

For that reason, any usage of the CLI can be accomplished using a remote copy as seen in the below install command.

Setup

Run the below command to install viv.

python3 <(curl -fsSL viv.dayl.in/viv.py) manage install

To access viv from within scripts you should add its location to your PYTHONPATH. By default viv will be installed to $XDG_DATA_HOME/viv or ~/.local/share/viv; you can customize this with --src.

export PYTHONPATH="$PYTHONPATH:$HOME/.local/share/viv"

Pypi (Not Recommended)

pip install viv

Why is this not recommended? Mainly because viv is all about hacking your sys.path. Placing it in its own virtual environment or installing in a user site directory may complicate this endeavor.

Usage

In any Python script with external dependencies you can add this line to automate vivenv creation and installation of dependencies.

__import__("viv").use("click")

To remove all vivenvs you can use the below command:

viv cache remove $(viv list -q)

To remove viv altogether you can use the included purge command:

python3 <(curl -fsSL viv.dayl.in/viv.py) manage purge

Equivalent commands from alternatives

pip-run

pip-run cowsay -- -m cowsay "moove over, pip-run"
python3 <(curl -fsSL viv.dayl.in/viv.py) run cowsay -- "moove over, pip-run"

python -m pip-run requests -- -c "import requests; print(requests.get('https://pypi.org/project/pip-run').status_code)"
python -m viv requests -b python -- -c "import requests; print(requests.get('https://pypi.org/project/viv').status_code)"

pipx

pipx install pycowsay
viv shim pycowsay

pipx run https://gist.githubusercontent.com/cs01/fa721a17a326e551ede048c5088f9e0f/raw/6bdfbb6e9c1132b1c38fdd2f195d4a24c540c324/pipx-demo.py
python3 <(curl -fsSL viv.dayl.in/viv.py) run \
  -s https://gist.githubusercontent.com/cs01/fa721a17a326e551ede048c5088f9e0f/raw/6bdfbb6e9c1132b1c38fdd2f195d4a24c540c324/pipx-demo.py

Bonus: use viv with just standalone snippet (37LOC)

--standalone will auto-generate a mini-function version of viv to accomplish the same basic task as using a local copy of viv. After generating this standalone shim you can freely use this script across Unix machines which have Python > 3.8. See examples/black for output of the below command.

viv freeze also supports --standalone.

python3 <(curl -fsSL viv.dayl.in/viv.py) shim black -o ./black --standalone --freeze

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1. You do need to have pip but surely you have pip already. ↩︎