Maybe a stupid question, but we just switched from

django-dotenv

to

python-dotenv

and with that from absolute to relative and a-lot-easier

.env

-File loading. But now my testing with Pants stopped working due to the fact (I guess) that it’s hermetic and the

.env

-File cannot be found. Is there a common way to use

.env

-Files inside Pants? At least I couldn’t find anything related to that topic inside the docs 🙂.

Or do I pass the absolute path to the

.env

-File like we did before?

You generally want to avoid absolute paths with Pants if possible. Think about trying to share cache hits when using a remote cache. Likely all users will have a different absolute path for a given thing and then any action pants performs that needs that path cannot have its results shared across users.

But now my testing with Pants stopped working due to the fact (I guess) that it’s hermetic and the

.env

-File cannot be found.

Your guess is correct. You have to declare dependencies on all the files you need. We take away that trouble for code dependencies (imports) and some other things with dep inference, but

.env

is not one of those. So you'll need a

file

(s?) target to own the

.env

and then you'll need to wire up a dependency on that target to everything that needs it.

Thanks for your response John! Do I want to package

.env

-Files inside of PEXs? In my eyes they are basically parameters of execution. So of course they can change behavior or even the build but this is a matter of loading environment-variables.

I injected confusion. PEX files are an internal detail of Pants. You won't be explicitly creating any PEXes at all, you'll just be running tests. Behind the scenes Pants uses PEXes to set this up.

I’m gonna try loading it as a file and wire the dependency on the test, then come back to you. I’m wondering though why such a high hold standard has no place in Pants yet.

Just no user with your case. For example, Toolhchain uses .env but not via python. It uses it via direnv.

What do you mean with “Python-specific .env handling”?

.env

-Files rarely have Python-specific things to them. Or do you mean when you’re executing a second language from your shell, you want the Environment-Variables loaded from the start? 🤔

I mean loading .env using Python code / libraries. With something like direnv, the .env is loaded transparently by the shell when you switch CWD. At that point the 12-factor env vars are exposed for any language runtime to see.

Yes that’s totally awesome. Thanks for enlightening me!

You'd then just use this in 1 spot to configure which .env loaded env vars to expose to all tests: https://www.pantsbuild.org/docs/reference-test#section-extra-env-vars

I think I’ll give that a try 😄 even if it takes me a bit longer to setup.

PS there are no stupid questions! only incomplete documentation

@enough-analyst-54434 I just switched our project from using 3 different implementations of “read this

.env

file” to direnv 😄. Gonna need to explain to my devs tomorrow but this does make more sense than using 3 additional libraries. I love it! Thank you so much! And Pants is happy as well 🚀