Install build or other dependencies from pyproject.toml

install-deps

#!/usr/bin/env python

import tomllib
import argparse
import sys
import subprocess


parser = argparse.ArgumentParser()
parser.add_argument(
    "-e", "--extras",
    help="Which extras to install; use `list` for options"
)
args = parser.parse_args()

config = tomllib.load(open("pyproject.toml", "rb"))

def get_config(key):
    d = config
    for subkey in key.split('.'):
        try:
            d = d[subkey]
        except KeyError:
            return None
    return d


if args.extras is None:
    # Install build dependencies
    key = 'build-system.requires'
    requires = get_config(key)
    if requires is None:
        print("Could not find build dependencies")
        print(f"Ensure pyproject.toml has `{key}` key")
        sys.exit(1)
else:
    # Install extras
    key = 'build-system.requires'
    extra_requires = get_config("project.optional-dependencies")
    if extra_requires is None:
        print("Could not find extra dependencies")
        print(f"Ensure pyproject.toml has `{key}` key")
        sys.exit(1)

    def print_extras():
        print("`extras` can be one of:\n")
        for key in extra_requires:
            print(f"- {key}")
        print()

    if args.extras == 'list':
        print_extras()
        sys.exit(0)

    if not args.extras in extra_requires:
        print(
            f"Extras `{args.extras}` not listed under "
            "[[project.optional-dependencies]] in pyproject.toml.\n"
        )
        print_extras()
        sys.exit(1)

    requires = extra_requires[args.extras]

cmd = ["pip", "install"] + requires
print("$ " + " ".join(cmd))
subprocess.run(cmd)