Can I use a requirements.in file instead of pyproject.toml?

[juftin]

I'm looking to leverage PDM for a hatch LockFile plugin - the current workflow I'm after is using hatch to create a requirements.in file - ultimately it's a loosely pinned requirements file format. I would then feed that file to PDM and create an exhaustive lock file from all the transitive dependencies. I'd really like to leverage PDM for generating the LockFile but it seems like it's only able to infer requirements from a Python build file like a pyproject.toml?

It's worth noting that the goal here is to create a lock-file for a hatch environment - an example environment might be only used for something like linting and wouldn't include runtime dependencies (although runtime lock files will be another use-case).

[frostming]

pdm import requirements.in

[juftin]

pdm import requirements.in

Thanks for the reply, unfortunately pdm import doesn't actually work for my needs.

Ideally I'm looking for something like pdm lock requirements.in --output locks/lint.yaml to build a lockfile without having to create a PDM table in my project.toml.

Ultimately the goal is to create a hatch plugin with pdm's locking superpowers.

[juftin]

A naive solution would be to create a temporary folder, write a pyproject.toml there with your dependencies, run pdm lock in that folder to generate the lock file, and copy it to its final destination (lint.toml).

Yeah, this is a good idea and probably the path I'll go down. I understand PDM is more than just a LockFile generator - so maybe what I'm trying to do is a bit against the spirit of the tool. But this is one feature that pip-compile supports that I think wouldn't be terribly hard to do with PDM. FWIW PDM supports almost all the same features I enjoy about hatch so maybe it's time to look at switching over rather than writing a plugin.

[pawamoy]

Maybe 😄

I think you could use PDM's API without too many difficulties: https://github.com/pdm-project/pdm/blob/main/src/pdm/cli/actions.py#L38.

[juftin]

Nice - I will take a look, thank you. That was one of my challenges with trying to use pip-compile for this - their API is tangled up with their CLI implementation. I love that pdm exposes final API methods like do_lock and do_sync

[frostming]

but be careful about that, PDM doesn't have a clear strategy of the stability of its APIs.

[pawamoy]

their API is tangled up with their CLI implementation

Amen. This is my nemesis. Let me guess... they use Click? Yep.