CLI with Fire

cli.py

from fire import Fire as _Fire
import sys


def Fire(target):
    """
    Changing Log Levels:
        To manage the logging level, you can set the LOGLEVEL environment variable before running the command.
        Supported values are DEBUG, CRITICAL, ERROR, WARNING, and INFO (the default). For example:

            LOGLEVEL=DEBUG {script} [subcomand] [parameter..]

    About MyPackage
    ---------------
    The MyPackage CLI is procedurally generated. Most tools include one or more subcommands, and you can view
    help documentation for each one. To view help for a specific command, try:

        {script} subcommand -- --help

    This documentation is also available online at:
        https://link.to.docs.site/

    We have made every attempt to generate tools that are safe, predictable, and easy to use. If this is not your
    experience, please report a bug or make a feature request using this link:
        https://support.request.site/

    """
    try:
        target.__doc__ += Fire.__doc__.format(script=sys.argv[0])
        _Fire(target)

    # catch common failures with common remediation actions
    except SignOnFailureException:
        print("Do you need to refresh your credentials?")
        raise SystemExit(1)
    except HealthCheckException:
        print("It isn't safe to run this command right now because reasons.")

some-service

#!/bin/env python
from lib import someservice

someservice.run()

someservice.py

from cli import Fire

class SomeServiceCLI:
    """some-service

    Command:
        some-service -- a tool for interacting with SomeService

    Description:
        This tool implements a command-line interface for SomeService.
    """

    def __init__(self):
        self._service = SomeServiceHelper()

    def is_alive(self, ipv6=True, ipv4=True):
        """some-service is-alive

        Command:
            some-service is-alive -- Determine if SomeService is responding on at least one interface.

        Description:
            This tool will print "True" if the service is responding to ping requests, or "False" otherwise.

        Examples:

            % some-service is-alive
            True

            % some-service is-alive ipv6=False
            False

            % some-service is-alive ipv4=True ipv6=False
            True
            
        Options:
        IPV6    Set to False to skip checking the IPv6 interface
        IPV4    Set to False to skip checking the IPv4 interface
        """
        if not (ipv6 or ipv4):
            raise RuntimeError("You must include at least one interface; see some-service is-alive -- --help")
        if ipv6 and self._service.ping6():
            return True
        elif ipv4 and self._service.ping():
            return True
        return False

def run():
    Fire(SomeServiceCLI())

% some-service is-alive --help
Type:        CLI
String form: <lib.someservice.SomeServiceCLI object at 0x7f31a5afdba8>
Docstring:   some-service is-alive

Command:
    some-service is-alive -- Determine if SomeService is responding on at least one interface.

Description:
    This tool will print "True" if the service is responding to ping requests, or "False" otherwise.

Examples:

    % some-service is-alive
    True

    % some-service is-alive ipv6=False
    False

    % some-service is-alive ipv4=True ipv6=False
    True

Changing Log Levels:
    To manage the logging level, you can set the LOGLEVEL environment variable before running the command.
    Supported values are DEBUG, CRITICAL, ERROR, WARNING, and INFO (the default). For example:
            LOGLEVEL=DEBUG some-service [subcomand] [parameter..]

About MyPackage
---------------
The MyPackage CLI is procedurally generated. Most tools include one or more subcommands, and you can view
help documentation for each one. To view help for a specific command, try:
    some-service subcommand -- --help

This documentation is also available online at:
    https://link.to.docs.site/

We have made every attempt to generate tools that are safe, predictable, and easy to use. If this is not your
experience, please report a bug or make a feature request using this link:
    https://support.request.site/

Options:
IPV6    Set to False to skip checking the IPv6 interface
IPV4    Set to False to skip checking the IPv4 interface

Usage:    some-service is-alive [IPV6] [IPV4]
          some-service is-alive [--ipv6 IPV6] [--ipv4 IPV4]