vrc

This is a configuration loader based on rc, extended by argument validation and --help.

const { Vrc } = require( 'vrc' );

const conf = new Vrc( 'myAppName', [
    { name: 'name', dflt: 'Jack', desc: 'Name to print', type: 'string' },
], { description: 'This tool solves any problem given' } ).run();

console.log( `Name: ${conf.get('name')}` );

Automatic help shows default values and actually used values.

Configuration

vrc( appName, conf ) : { conf, invalidNames }

Returns the conf object from rc and a list of invalid names where the user supplied wrong parameters (e.g. string instead of number). Invalid values will be replaced by their defaults.

A configuration entry takes the following arguments:

• name: Name of the variable/parameter
• desc: Description, shown in the help
• dflt: Default value
• type: Supported values: 'string', 'number', 'boolean', number[], number[][]
• options: Array holding valid options for the argument. Currently only for strings.

Number arrays are passed as comma-separated values and are converted; 1,3,42 results in [1,3,42].

TypeScript usage

Vrc can be used with limited typing support by passing an interface to the constructor.

import { Vrc } from 'vrc';

interface Conf {
    balloons : number;
    colour : string;
}

const conf = new Vrc<Conf>( 'balloon', [
    { name: 'balloons', type: 'number', dflt: 99, desc: 'Number of balloons' },
    { name: 'colour', type: 'string', dflt: 'red', desc: 'Balloon colour' },
] ).run();

console.log( conf.conf.balloons ); // 99

Changelog

v2.1.0 – 2020-04-02

This version fixes the way arguments are marked as invalid and does not replace invalid user arguments by default values anymore as this is potentially dangerous.

• Added VrcConf.unnamedArgs which contains positional/unnamed arguments
• Added VrcConf.printArgs() to print a summary of all arguments
• Added the secr modifier for arguments which causes them not to be printed with the above function
• Breaking: Invalid arguments are not replaced by default values anymore.

v2.0.0 – 2020-03-03

• Breaking: Configuration is now created with new Vrc() which can be typed in TypeScript.
• Breaking: To evaluate the help parameter, use new Vrc().run().
• Removed: VrcConf.invalidNames

v1.11.0 – 2020-03-03

• Added: vrc now returns a VrcConf object which can e.g. check if an argument is using a default value or a user-provided value. The object is backwards compatible and still exhibits the old properties.

v1.10.0 – 2020-03-02

• Added options for string parameters to define possible values

v1.9.0 – 2020-02-10

• Changed: Long description lines are now wrapped in the help output.

v1.8.0 – 2020-01-08

• Added support for string[]