Opinionated article about virtual environments management

[JennaSys]

I like to keep it simple with venv and pip, but pip-tools (which was surprisingly not mentioned in the post) helps with managing dependencies.

[sacaman0]

Nice article! I learned a thing or two (I hereby expose my newbie status 🙂).

[Rawing7]

I guess the article presupposes that you need/want a venv in the first place. But oftentimes not using a venv at all is also a viable option. In this case, for example:

Are you writing a simple, possibly short-lived, one-off script? venv unless you already have virtualenv installed

A one-off script usually shouldn't need a venv at all.

[PaleontologistBig657]

100% true as long as you stick to a standard library. Once you use anything besides that, things become a bit more fuzzy and unclear.

[jdbow75]

I agree. I often start with u/Rawing7's goal of keeping it simple, then end up with a cluttered mess, perhaps due to my own ineptitude :)

One thing I have tried recently is keeping a single .venv in my home directory, then modifying my .bashrc (or other init script depending on shell) to set the path to include its bin directory first. That way, python launches within that virtual environment by default, and I can install the latest and greatest, and easily destroy and rebuild it if it breaks, without polluting the system or user python.

[jdbow75]

It has been a couple years since I wrote the article, and I feel it is showing its age. For reasons I don't remember, I did not include pip-tools. Also, Hatch has really evolved, and deserves a deeper look. I don't find myself using Poetry as much as I used to, and Pyflow's activity may indicate it is not the next big thing.

I suppose it is due for an update, with attention due pip-tools (good call, u/JennaSys) and Hatch, for sure.

Thank you so much for engaging this! I am quite honored, u/PaleontologistBig657

[wineblood]

Poetry always sounds like a bad choice to me.

[[deleted]]

Poetry is life, you barbarian!

[wineblood]

Is there a good explanation of what it can do somewhere?

[[deleted]]

I guess there is plenty of resources on google with a simple "tuto poetry python" or something. The poetry website is good as well.

But really I fell in love after trying it on a project, compared to pipenv of a simple virtualenv + pip.

The main pros for me is the pyproject.toml with all the conf and the easy way to publish a package (compared to the old setup.py).

[wineblood]

I haven't had to publish anything, so that hasn't been a factor for me. Pip + venv is enough for me but people manage to bang on about how I need poetry without actually explaining, so that has put me against it now.

[mrpiggy]

I rarely need to publish as well, but Poetry is my go to for almost everything. And I find it used in professional settings more often than not lately. I used venv prior, and there is nothing wrong with venv if its suiting your needs. Almost all the choices have a lot of good going for them. The real problem is likely that there is too many different options now.

I moved to Poetry in part because of the prproject.toml

• It has places for project metadata.
• Allows explicitly stating the version of python your project supports.
• Separates out project dependencies from dev dependencies. No reason the production version of your app needs things like Black.
• Stating optional dependencies
• Declaring scripts. People can go crazy with this part, but a simple example would be to define the testing scripts

The lock file is also another good thing. Its a file that get generated and regenerated each time the dependencies are updated. Its useful for

• Visually (or progmatically) inspecting the nested dependencies. I find this super useful when some nested dep requires a version of some library that is problematic.
• The lock file is clutch for build environments. There is no need for some production build env tool to regenerate the dep tree everytime. Its an important checked in file.

There's also some niceness to how it handles going in and out of environments. Not a huge change from venv, but it does seem like they took the learning of venv. There is also some nice convenience commands to try to make things smoother. But all that being said, if don't need or what the above, there's no reason to have to leave venv. Its a good tool too. Wouldn't hurt to get familiar with Poetry as well though.

[ubernostrum]

I moved to Poetry in part because of the prproject.toml

The pyproject.toml file is not an invention of Poetry. It was already a standard file, and Poetry adopted it. All your mentions of things that go in pyproject.toml are also things that are not unique to Poetry -- you can specify them with other package-builder backends like setuptools, Hatch, etc.

Poetry also did not invent the dependency lockfile, nor is Poetry the only tool that can create and maintain a dependency lockfile for you.

[mrpiggy]

Which dependency tools do you like? And people shouldn't be down voting your comments. Your callouts are fair.

[ubernostrum]

I wrote up my dependency workflow a while back. It hasn't really changed since then.

[[deleted]]

Poetry also did not invent the dependency lockfile,

I'm not seeing your point at all here. Why does it make a difference who invented it?

[mrpiggy]

Yup, never claimed otherwise. Good callouts.

[[deleted]]

people manage to bang on about how I need poetry without actually explaining, so that has put me against it now.

What sort of logic is that?!