@noresources/command

A lightweight command line interface definition package focusing on reusability, extensibility and a clean API.

Installation

npm install --save @noresources/command

Features

• Plain object based command component descriptors
  • Program
  • Command, subcommands
  • Option
  • Positional
  • Parameter (option and positional argument value type)
• Chain-based program builder API
• Exporter to well-known command packages
  • Commander.js

Examples

Component descriptors

Commands, options and positional arguments can be declared using a simple plain javascript object.

export const Verbosity = {
    'type': 'counter',
    'documentation': 'Verbosity level',
    'initial': 0,
    'names': ['verbosity', 'v']
};

Then, a factory function will creates the correct class instance.

import { createOption } from "@noresources/command"
const option = createOption(Verbosity);

Builder API

The ProgramBuilder class provides a fluent interface to define the whole program interface using method chaining.

import { ProgramBuilder } from "@noresources/command"

const builder = new ProgramBuilder;
builder.name('chatbot')
    .version('1.2.3')
    .option(Verbosity) // out option descriptor presented above.
    .positional({
        documentation: 'Some text to insert in conversation'
    }).handler(function (input) {
            if (input.options.verbosity > 2) console.log('Bark bark')
            if (input.arguments.length)
                console.log (input.arguments[0])
            console.log ('This program is not really meaningful'),
    })

Exporter to commander.js

For now, this package does not provide a command line parser by itself. It relies on well established parser Commander.jsa to for parsing.

Converting a @noresources/command program to a Commander.js command is made with a simple function call.

import {	createCommand } from '@noresources/command/commander'

const command = createCommand(builder.program); // assuming builder is the ProgramBuilder instance defined above.
command.parse ();

Note that the commander package is not included in @noresources/command package dependencies. You have to install it manually to usie this feature.