click shared option boilerplate

click-shared-option-boilerplate.py

"""
A shared option boilerplate with click.

The top-level do NOT collect enough information about shared options because of how click work.
To achieve the goal, the logic handling shared options must be postponed until shared options in interest are collected.

=====================
This is free and unencumbered software released into the public domain.

Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.

In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
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ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

For more information, please refer to <http://unlicense.org/>
"""

from dataclasses import dataclass
from typing import Any, Dict

import click


@dataclass()
class Repo:
    """
    Being a dataclass for convenience
    The logic handling shared options is located in `finish()`
    """
    verbose: int = 0
    finished: bool = False

    def filter_options(self, kwargs) -> Dict[str, Any]:
        """Return a dict without shared options"""
        if self.finished:
            raise ValueError("finish() has been called")

        kwargs = dict(kwargs)
        self.verbose += kwargs.pop('verbose', 0)
        return kwargs

    def consume_options(self, kwargs):
        """All options are consumed or raise"""
        empty = self.filter_options(kwargs)

        if empty:
            raise ValueError(f"Unknown option {next(iter(empty))}")

    def finish(self, options=None):
        if options:
            self.consume_options(options)

        if self.finished:
            raise ValueError("finish() has been called")
        self.finished = True

        del options

        verbose = self.verbose
        print(f"Configure logging based on verbosity = {verbose}")


pass_repo = click.make_pass_decorator(Repo, ensure=True)


def shared_options(func=None):
    def decorate(fn):
        options = (
            click.option('--verbose', '-v', count=True),
        )

        for opt in options:
            fn = opt(fn)

        fn = pass_repo(fn)

        return fn

    if callable(func):
        return decorate(func)
    return decorate


@click.group()
@shared_options()
def cli(repo: Repo, **kwargs):
    repo.consume_options(kwargs)

    print('repo in cli', repo)


@cli.group()
@shared_options()
def group_a(repo: Repo, **kwargs):
    repo.consume_options(kwargs)

    print('repo in feed', repo)


@group_a.command()
@click.argument('argument')
@shared_options()
def command_b(repo: Repo, argument: str, **kwargs):
    repo.finish(kwargs)

    print("Argument is", argument)


if __name__ == '__main__':
    cli()