airsequel / oclis

The obvious CLI specification format. You define the spec, Oclis generates the code! Support for PureScript so far. PRs for more languages appreciated!

Oclis

CLI (Command Line Interface) app builder based on a simple, obvious specification file.

Motivation

Building a CLI application is a repetitive task. The same code is written over and over again. But fear not, Oclis is here to help you out!

Usage

1. cargo install oclis
2. oclis init - Creates an oclis.ncl specifcation file.
3. Adapt the specification file to your liking.
   (Check out the examples directory for inspiration.)
4. Run oclis build to generate the CLI parsing code
   (It automatically detects the main repo language, but only PureScript is supported at the moment.)
5. Add missing dependencies to your project.
   (E.g. for PureScript check out the spago.yaml file.)
6. Define the handler functions for your commands.
   (Check out the main function of Transity for an example.)
7. Commit the generated code to the repository.

How It Works

Processing Pipeline of the Generated CLI App

Unsupported CLI designs

Some features of other CLI frameworks are deliberately not supported:

• Specifying a flag several times. (e.g. tar -v -v -v) This is error prone as it's easy to accidentally add it several times. Use a numerical verbosity flag instead (e.g. tar -v=3) or define your own counting system (e.g. tar -v=xxx)
• Specifying flags/options after the arguments. (e.g. pandoc in.md --output=out.pdf) Disallowing this helps to prevent errors from accidentally providing an argument which is understood as a flag/option. Suggested alternatives:
  • Sub-command: pandoc convert in.md out.pdf
  • Option first: pandoc --output=out.pdf in.md
  • Extra option: pandoc --input=in.md --output=out.pdf

Related

Other CLI Builders

• CLI Definition Language - DSL for defining command line interfaces of C++ programs.
• Decli - Declarative CLI tool builder.
• docopt - Command-line interface description language.
• make-cli - Declarative CLI framework for Node.js.

Manual CLI Frameworks

Check out the repo awesome-cli-frameworks for a full overview.

Specifications

• clig.dev - Command Line Interface Guidelines.
• GNU Table of Long Options
• Heroku CLI Style Guide
• OpenAutoComplete - CLI autocomplete specification.
• POSIX Utility Conventions

Generate GUIs From CLI

• Claui - A GUI generator for clap using egui.
• Gooey - Turn CLI programs into a full GUI application.
• Klask - Automatically create GUI applications from clap apps.

Generate GUIs From Simple Code

• Sparkle - Infer user interfaces from type signatures.
• Streamlit - Turns data scripts into shareable web apps.