Automate creation of virtual environments in Python 3 projects
Creates a Python virtual environment directory in a new or existing project
using python3 -m venv. After the environment is created, this tool will
update pip, setuptools and wheel. Finally, it will detect a
requirements.txt file and pip install -r it.
This tool will also create a .gitignore file if none is present.
py-mkvenv is available for Linux as a standalone binary from github
Source code is available from github at the py-mkvenv project page. This directory will of course have no virtual environment specific to your system.
This tool exists to perform most of the following steps, but if you don't have it operational yet, you'll need to manually bootstrap the virtual environment. Here's how:
From within the py-mkvenv directory, set up the venv
$ cd py-mkvenv
$ python3 -m venv .venv
From here on out, make sure you're working in the environment
$ source ./.venv/bin/activate
Update the tools
$ python -m pip install --upgrade pip setuptools wheel
Install the project's dependencies using the requirements.txt file
$ pip install -r requirements.txt
You should now be able to run it, type check it with mypy, etc.
$ ./py-mkvenv # Run it
$ mypy py-mkvenv # Type check with mypy
Over time, you may install more libraries using pip install. Get a list of
those and check these changes into source control if necessary.
$ pip freeze > requirements.txt
If desired, deactivate the virtual environment in your shell
$ deactivate
It's important to build the distributable binary on an older distribution so it's compatible with many systems. In practical terms Ubuntu 14.04 is a good choice for this.
The stock version of Python 3 on Ubuntu 14.04 is 3.4 but we need a higher version.
So, install Python 3.6:
# add-apt-repository ppa:deadsnakes/ppa
# apt-update
# apt install python3.6 python3.6-dev python3.6-venv
Use an earlier version of py-mkvenv to make the virtual environment or, if that isn't possible:
$ python3.6 -m venv .venv
$ ./.venv/bin/python -m pip install --upgrade pip setuptools wheel
$ . ./.venv/bin/activate
$ pip install -r requirements.txt
To build the distributable binary, run util/bin/mkdist.sh. If all goes well,
you should have a binary named something like this:
dist/py-mkvenv-1.6
Replace all == with >= in `requirements.txt, then
$ pip install --upgrade --force-reinstall -r requirements.txt
$ pip freeze > requirements.txt
And check this new version of requirements.txt into source control.
Dino Morelli [email protected]