A common meta thing that I need in python is to find the version of a package.
Most of the time I reach for package_name.__version__, but that does not
always work.
but not all projects have a __version__ #
In searching the internet for an answer nearly every one of them pointed me to
__version__. This works for most projects, but is simply a convention, its
not required. Not all projects implement a __version__, but most do. I’ve
never seen it lie to me, but there is nothing stopping someone from shipping
mismatched versions.
If you maintain a project ship a __version__ #
I appreciate it
While its not required its super handy and easy for anyone to remember off the
top of their head. It makes it easy to start debugging differences between
what you have vs what you see somewhere else. You can do this by dropping a
__version__ variable inside your __init__.py file.
## __init__.py
__version__ = 1.0.0
SO #
stack overflow saves the day
Special thanks to this
Stack Overflow post
for answering this question for me.
So what do you do… #
importlib
Your next option is to reach into the package metadata of the package that you
are interested in, and this has changed over time as highlighted in the stack
overflow post.
for Python >= 3.8:
from importlib.metadata import version
version('markata')
# `0.3.0.b4`
I only really use python >= 3.8 these days, but if you need to implement it for
an older version check out the stack overflow post.
Another option.. #
use the command line
Another common option uses pip at the command line.
❯ pip show markata
Name: markata
Version: 0.3.0b4
Summary: Static site generator plugins all the way down.
Home-page: https://markata.dev
Author: Waylon Walker
Author-email: [email protected]
License: MIT
Location: /home/waylon/git/waylonwalker.com/.venv/lib/python3.11/site-packages
Requires: anyconfig, beautifulsoup4, checksumdir, diskcache, feedgen, jinja2, more-itertools, pathspec, pillow, pluggy, pymdown-extensions, python-frontmatter, pytz, rich, textual, toml, typer
Required-by:
And if the package implements a command line its common to ship a version
command such as --version or -V.
❯ markata --version
Markata CLI Version: 0.3.0.b4
Why did I need to do this? #
Well we have a cli tool that wraps around piptools and we wanted to include the
version of piptools in the comments that it produces dynamically. This is why
I wanted to dynamically grab the version inside python without shelling out to
pip show. Now along with the version of our internal tool you will get the
version of piptools even though piptools does not ship a __version__
variable.
Fin #
In the end, I am glad I learned that its so easy to use the more accurate
package metadata, but still appreciate packages shipping __version__ for all
of us n00b’s out here.
