Features

• Argparse friendly:
  • Reuse as much as possible from argparse, but allow a new modular way to built CLI.
  • If you know argparse, then you already know how to use clak.
  • Same API:
    • argparse.ArgumentParser() becomes class MyApp(Parser):
    • .add_argument(...) becomes dest = Argument(...)
    • .add_subparser(...) becomes subcmd1 = SubCommand(...)
  • Extended API:
    • .add_argument("--option", "o", help="Optional argument") => option = Opt("--option", "o", help="Optional argument")
    • .add_argument("param", help="Positional argument") => param = Arg(help="Positional argument")
    • .add_suparser(...) => subcmd1 = Cmd(ChildrenParserClass, help="Subcommand help")

• Class based approach:
  • Use Python class to provide declarative command line.
  • Since we use class, we can take advantage of Python inheritance to create CLI.
    • Including organizing command in a tree structure.
    • Inherit and share settings among different class, to allow maximum reusability.
  • Hide internal argparse implementation from user, so you can focus on your app.

• Build git-like CLI with ease
  • Rely on arparse subparser functionality.
  • Pythonic class based approach to represent.
  • Each subcommands are Parser instances, referenced via the SubCommand field.

• Easy sub-command discovery
  • All possible command are show in the root help
  • All subcommands display indiviudal and customizable help message.

• Modular components and reusable components:
  • Help:
    • Comprehensive help message with command tree display.
    • Manage --help and -h flags.
    • Easily change usage, description or epilog
  • Logging:
    • Configure and enable Basic Logger
    • Provide per Node logger
    • Provide --verbose and -v,-vv,-vvv flags
  • Config:
    • Use XDG Base Directory Specification to provide config files and directory paths.
    • Load yaml, json, toml, ini files easily
  • Completion:
    • Provide completion or --complete flag to generate completion script.
    • Support most common shell via the argcomplete library.
  • More to come ...
    • Environment var support
    • Automatic app config reader/writer
  • Build your own:
    • Reuse your existing code, your favorite CLI options, put them in a library and ship it.