Use external Node.js installation via PyPI wheels

[agriyakhetarpal]

Description

This PR swaps out our Node.js dependency by including the (unofficial) binaries from PyPI: https://github.com/njzjz/nodejs-wheel. This means that pyodide venv's Python interpreter should no longer need to rely on an Node.js installation.

Closes #119

[agriyakhetarpal]

A blocker early into the implementation:

We would still need to address how to make pyodide venv work. When we install pyodide-build in a virtual environment, say, in a folder named venv/, it will now install Node.js only into that virtual environment and not globally.

Now, when we'll create a virtual environment using pyodide venv, say, at .venv-pyodide and then activate it, we won't have node on our PATH as it existed only in the other environment. We'll need to install nodejs-wheel inside the virtual environment.

Then, even if we do so, https://github.com/njzjz/nodejs-wheel/blob/4dfd45dbffbe412dc216746eb71ec1fc73d8ed50/nodejs_wheel/executable.py uses subprocesses, which won't work... their implementation is in contrast to my approach, where I use the execv syscall: https://github.com/agriyakhetarpal/hugo-python-distributions/blob/12aea38b785434c89b92873248a76c69b793cf8c/hugo/cli.py#L68

[agriyakhetarpal]

Never mind – the tests passed, and I'm not sure how. :D

[agriyakhetarpal]

...and it doesn't work, as we don't have wasm32 binaries on PyPI or on jsDelivr:

pip install nodejs-wheel
Looking in indexes: https://pypi.org/simple, file:///Users/agriyakhetarpal/Library/Caches/.pyodide-xbuildenv-0.30.1.dev0+ga4b038c.d20250408/0.27.5/xbuildenv/pyodide-root/package_index
WARNING: Location 'file:/Users/agriyakhetarpal/Library/Caches/.pyodide-xbuildenv-0.30.1.dev0+ga4b038c.d20250408/0.27.5/xbuildenv/pyodide-root/package_index/nodejs-wheel/' is ignored: it is neither a file nor a directory.
Collecting nodejs-wheel
  Downloading nodejs_wheel-22.14.0-py3-none-any.whl.metadata (5.6 kB)
WARNING: Location 'file:/Users/agriyakhetarpal/Library/Caches/.pyodide-xbuildenv-0.30.1.dev0+ga4b038c.d20250408/0.27.5/xbuildenv/pyodide-root/package_index/nodejs-wheel-binaries/' is ignored: it is neither a file nor a directory.
INFO: pip is looking at multiple versions of nodejs-wheel to determine which version is compatible with other requirements. This could take a while.
  Downloading nodejs_wheel-22.13.1-py3-none-any.whl.metadata (5.6 kB)
  Downloading nodejs_wheel-22.13.0-py3-none-any.whl.metadata (5.3 kB)
  Downloading nodejs_wheel-22.12.0-py3-none-any.whl.metadata (5.3 kB)
  Downloading nodejs_wheel-22.11.0-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.18.0-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.17.0-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.16.0-py3-none-any.whl.metadata (3.8 kB)
INFO: pip is still looking at multiple versions of nodejs-wheel to determine which version is compatible with other requirements. This could take a while.
  Downloading nodejs_wheel-20.15.1-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.15.0-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.14.0-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.13.1-py3-none-any.whl.metadata (3.8 kB)
  Downloading nodejs_wheel-20.13.0.post1-py3-none-any.whl.metadata (2.6 kB)
INFO: This is taking longer than usual. You might need to provide the dependency resolver with stricter constraints to reduce runtime. See https://pip.pypa.io/warnings/backtracking for guidance. If you want to abort this run, press Ctrl + C.
ERROR: Cannot install nodejs-wheel==20.13.0.post1, nodejs-wheel==20.13.1, nodejs-wheel==20.14.0, nodejs-wheel==20.15.0, nodejs-wheel==20.15.1, nodejs-wheel==20.16.0, nodejs-wheel==20.17.0, nodejs-wheel==20.18.0, nodejs-wheel==22.11.0, nodejs-wheel==22.12.0, nodejs-wheel==22.13.0, nodejs-wheel==22.13.1 and nodejs-wheel==22.14.0 because these package versions have conflicting dependencies.

The conflict is caused by:
    nodejs-wheel 22.14.0 depends on nodejs-wheel-binaries==22.14.0
    nodejs-wheel 22.13.1 depends on nodejs-wheel-binaries==22.13.1
    nodejs-wheel 22.13.0 depends on nodejs-wheel-binaries==22.13.0
    nodejs-wheel 22.12.0 depends on nodejs-wheel-binaries==22.12.0
    nodejs-wheel 22.11.0 depends on nodejs-wheel-binaries==22.11.0
    nodejs-wheel 20.18.0 depends on nodejs-wheel-binaries==20.18.0
    nodejs-wheel 20.17.0 depends on nodejs-wheel-binaries==20.17.0
    nodejs-wheel 20.16.0 depends on nodejs-wheel-binaries==20.16.0
    nodejs-wheel 20.15.1 depends on nodejs-wheel-binaries==20.15.1
    nodejs-wheel 20.15.0 depends on nodejs-wheel-binaries==20.15.0
    nodejs-wheel 20.14.0 depends on nodejs-wheel-binaries==20.14.0
    nodejs-wheel 20.13.1 depends on nodejs-wheel-binaries==20.13.1
    nodejs-wheel 20.13.0.post1 depends on nodejs-wheel-binaries==20.13.0

To fix this you could try to:
1. loosen the range of package versions you've specified
2. remove package versions to allow pip to attempt to solve the dependency conflict

WARNING: Location 'file:/Users/agriyakhetarpal/Library/Caches/.pyodide-xbuildenv-0.30.1.dev0+ga4b038c.d20250408/0.27.5/xbuildenv/pyodide-root/package_index/pip/' is ignored: it is neither a file nor a directory.
ERROR: ResolutionImpossible: for help visit https://pip.pypa.io/en/latest/topics/dependency-resolution/#dealing-with-dependency-conflicts

Here, we don't particularly need a wasm32 wheel for https://pypi.org/search/?q=+nodejs-wheel-binaries, just a Linux or macOS wheel that gets installed into the venv despite the incompatibility (either through pip install --target or similar).

At this point, I think that this is something that isn't worth doing, unless we want to be super hacky. I'd say it's okay to include a bunch of hacks as we've discussed elsewhere, but this one feels too quirky. We could easily ask users to install Node.js externally and globally, whether it is through Homebrew, https://github.com/njzjz/nodejs-wheel, or whichever package manager they use on their system.

What do you think, @hoodmane?

[ryanking13]

...and it doesn't work, as we don't have wasm32 binaries on PyPI or on jsDelivr:

I don't understand this. Why is it needed to install nodejs inside the pyodide venv? I thought we need to install it in the host environment.

---

I'm personally against including Node.js in pyodide-build, for the same reason I'm against including emscripten in pyodide-build. If Node.js is supported by a package with enough trusted people and users (like cmake supported by the scikit-build team), I think it's fine, but, njzjz/nodejs-wheel seems a bit unreliable for us to trust and use.