Question about adding another local project as a dependency

[mark13hardware]

I'm working on a project that's going to be installed onto a computer that doesn't have network access. Right now I've created two libraries, foo and bar. I thought I could just create a .whl for each, copy them from my development workstation to removable media, and install them on the destination computer with pip. But the foo library has the bar library as a dependency, and I'm not sure how to do this in poetry.

Running "poetry add bar ../bar" in the foo project (../bar is the path to where I'm developing the bar library) seemed to do the trick, but it looks like this results in a foo.whl that always wants to satisfy it's dependency on bar by building it with poetry in /home/mark13/foo instead of using of using the. I can create a directory like that in the destination computer, but installing poetry would be pretty difficult without network access.

As far as I can tell, the proper thing to do is add a source (https://python-poetry.org/docs/cli/#source-add) where poetry can find the bar library, then just do "poetry add bar". But as far as I can tell from the poetry docs, poetry doesn't support sources that aren't web servers. I did hope "poetry source add --priority=supplemental /home/mark13/foo" or "poetry source add --priority=supplemental file:///home/mark13/foo" would work, but both give the error: "A custom source cannot be added without a URL."

I can't upload to pypi as it's proprietary code, and I don't have access to a web server I can upload the packages to. I think I could figure out how to set up a python-based simple repository (https://peps.python.org/pep-0503/), but I was hoping I wouldn't have to go that far.

Is there a way for me to get poetry to create a .whl for the foo library that simply has the foo library as a dependency? Such that installing foo.whl via pip doesn't trigger trying to build bar via poetry?

[agammann]

With Poetry 2.x, you can keep a local path for development while putting a normal version requirement in the built wheel. In foo/pyproject.toml, the relevant parts would be:

[project]
name = "foo"
version = "1.0.0"
requires-python = ">=3.12"
dependencies = ["bar>=1.0.0,<2.0.0"]

[tool.poetry.dependencies]
bar = { path = "../bar", develop = true }

[build-system]
requires = ["poetry-core>=2.0.0,<3.0.0"]
build-backend = "poetry.core.masonry.api"

Here project.dependencies supplies the wheel metadata; tool.poetry.dependencies supplies Poetry's local dependency information for locking/installing. This behavior is documented in project.dependencies and tool.poetry.dependencies.

Build both projects on the development machine (poetry build -f wheel in each), then copy their wheels into one wheelhouse directory on the offline computer. Install with that computer's Python:

python -m pip install --no-index --find-links=wheelhouse "foo==1.0.0"

Pip finds the matching bar wheel there, so the target needs neither your development directory nor Poetry. Include wheels for any other runtime dependencies too, with versions and platform/Python compatibility appropriate for the target.

I tested this with Poetry 2.5.1: development installation used ../bar, but the built foo wheel contained Requires-Dist: bar (>=1.0.0,<2.0.0) with no path reference. Installing into a fresh environment using --no-index and only the two wheels succeeded, and importing foo imported bar. Pip documents this under installing from local packages.