Samovar

Motivation

I've been using Optimist and while it's not bad, it's hard to use for sub-commands in a way that generates nice documentation. It also has pretty limited support for complex command lines (e.g. nested commands, splits, matching tokens, etc). Samovar is a high level bridge between the command line and your code: it generates decent documentation, maps nicely between the command line syntax and your functions, and supports sub-commands using classes which are easy to compose.

One of the other issues I had with existing frameworks is testability. Most frameworks expect to have some pretty heavy logic directly in the binary executable, or at least don't structure your code in a way which makes testing easy. Samovar structures your command processing logic into classes which can be easily tested in isolation, which means that you can mock up and spec your command-line executables easily.

Usage

Please browse the source code index or refer to the guides below.

Releases

Please browse the releases for more details.

See Also

• Teapot is a build system and uses multiple top-level commands.
• Synco is a backup tool and sends commands across the network and has lots of options with default values.
• Bake is an alternative task runner that makes it easy to expose Ruby methods as command-line tasks.

Contributing

We welcome contributions to this project.

1. Fork it.
2. Create your feature branch (git checkout -b my-new-feature).
3. Commit your changes (git commit -am 'Add some feature').
4. Push to the branch (git push origin my-new-feature).
5. Create new Pull Request.

Developer Certificate of Origin

In order to protect users of this project, we require all contributors to comply with the Developer Certificate of Origin. This ensures that all contributions are properly licensed and attributed.

Community Guidelines

This project is best served by a collaborative and respectful environment. Treat each other professionally, respect differing viewpoints, and engage constructively. Harassment, discrimination, or harmful behavior is not tolerated. Communicate clearly, listen actively, and support one another. If any issues arise, please inform the project maintainers.

Future Work

Multi-value Options

Right now, options can take a single argument, e.g. --count <int>. Ideally, we support a specific sub-parser defined by the option, e.g. --count <int...> or --tag <section> <tags...>. These would map to specific parsers using Samovar::One and Samovar::Many internally.

Global Options

Options can only be parsed at the place they are explicitly mentioned, e.g. a command with sub-commands won't parse an option added to the end of the command:

command list --help

One might reasonably expect this to parse but it isn't so easy to generalize this:

command list -- --help

In this case, do we show help? Some effort is required to disambiguate this. Initially, it makes sense to keep things as simple as possible. But, it might make sense for some options to be declared in a global scope, which are extracted before parsing begins. I'm not sure if this is really a good idea. It might just be better to give good error output in this case (you specified an option but it was in the wrong place).

Shell Auto-completion

Because of the structure of the Samovar command parser, it should be possible to generate a list of all possible tokens at each point. Therefore, semantically correct tab completion should be possible.

As a secondary to this, it would be nice if Samovar::One and Samovar::Many could take a list of potential tokens so that auto-completion could give meaningful suggestions, and possibly improved validation.

Short/Long Help

It might be interesting to explore whether it's possible to have -h and --help do different things. This could include command specific help output, more detailed help output (similar to a man page), and other useful help related tasks.