argtoml 0.5.4

Add the keys from a .toml file to your CLI as arguments. Their values default to the values in the .toml file.

README

The argtoml package wraps around argparse. It adds the content of a toml file to the cli options. After parsing, it creates a types.SimpleNameSpace object.

install

Argtoml has no mandatory dependencies outside of pythons standard library.

pip install argtoml

You can optionally install tomli_w if you want to save your configuration at runtime.

pip install 'argtoml[save]'

usage

If there's a src/config.toml

debug = true
home = "~"

[project]
author = "Jono"
name = "argconfig"
pyproject = "./pyproject.toml"

and a src/__main__.py

from argtoml import parse_args  # , ArgumentParser

args = parse_args(path=True)
print(args.debug)
print(args.home)
print(args.project.author)
print(args.project.name)
print(args.project.pyproject)

then the shell can look like

$ pwd
/home/jono/project
$ python src/__main__.py --project.name argtoml --no-debug
False
/home/jono
Jono
argtoml
/home/jono/project/pyproject.toml

documentation

There is none, the code is not that large, but I expect you to only use:

parse_args(
  # An argparse parser for adding extra arguments not present in the toml.
  parser: Optional[argparse.ArumentParser] = None,
  # An extra help message.
  description: str = "",
  # The location of the toml file.
  toml_path: pathlib.Path = Path("config.toml"),
  # The dictionary in which to look for the toml file.
  toml_dir: Optional[TPath] = None,
  # Whether to try to interpret strings as paths.
  base_path: Union[Path, bool] = True,
  # Whether to look for the toml file in the parent of the toml_dir folder.
  grandparent: bool = True
) -> SimpleNamespace

save(args: Union[SimpleNamespace, dict], path: pathlib.Path):
  with open(path, "wb") as f:
    tomli_w.dump(args, f)

toml file location

You are encouraged to specify the location of the toml file when calling parse_args with an absolute path like this:

parse_args(toml_path="/home/user/dir/my_config.toml")

If you provide a relative path, argtoml will look for my_config.toml in the package directory if the main file using argtoml is from a package, otherwise argtoml will look for my_config.toml in the same directory as the main file. This automatic toml-finding function might change in the future, so probably just provide absolute paths.

packaging

If you want to ship a toml file with your package, make sure to add the toml file to your package. You should also call parse_args with a relative toml_path.

notes

This is a personal tool thus far, some idiosyncrasies remain:

• Adding dotted arguments not present in the toml might break everything I didn't even test this.
• I don't feel like adding other formats but toml.
• I don't know if, in the above example, the user can do something like python __main__.py --project {author="jo3"} --project.author jjj, but it should crash if they do this.
• Interpreting strings as paths probably only works with unix style paths.

todos

• Add toml comments as argument descriptions.
• Pretty-print the output of parse_args.
• Load and merge multiple toml files