yargs-config

Configuration object wrapper for nested configs with yargs integration. Extends nested-config with runCmd function.

JSDoc

API docs are available on the wiki.

Usage

yargs-config is itself a configuration object. All your current settings are stored in it. It keeps track of default options for you as well.

Initialize with your default settings

Create new config object using create(overrides [object], defaults [object]).

const yc = require('yargs-config');

let defaults = {
    yourOption: 1,
    nested: {
        option: "two"
    },
    meta: {
        yourOption: 'This is my option',
        nested: {
            option: 'This is my nested option'
        }
    }
};

let config = yc.create({}, defaults);

Notice the structure of meta object. It is used to populate yargs configuration. You can use either short form and provide just the description as shown above, or you can provide full meta object.

// ...
meta: {
    yourOption: {
        desc: 'This is my option',
        alias: 'y'
        // default: 1,     // will be filled automatically anyway
        // type: 'number'  // will be filled automatically anyway
    }
    // ...
}

default and type will be determined automatically, so no need to fill them out explicitly. Note that if config property is not inside meta object, it will not be exposed through yargs.

Update current settings

let overrides = {
    yourOption: 2,
    nested: {
        option: "three",
    },
};

config.add(overrides, {});  // performs deep merge into current config state

Access settings

config.yourOption;  // 2
config.getDefault('yourOption');  // 1
config.nested.option;  // "three"
config.getDefault('nested.option');  // "two"

Run yargs

runFromCmd(propStr [string], callback)

Starts command-line application with yargs, supporting piped inputs.

• propStr - where to look for settings in case of nested config (e.g. consider propStr as the root). Leave empty for using whole object.
• callback - calls when done with (err, data, argv), where data is stdin and argv is parsed yargs argv object.

if (!module.parent) {
  // Running from CLI
  config.runFromCmd('', (err, data, argv) => {
    // err is null if ok
    console.log(`This is input: ${data}`);
    console.log(`These are passed settings: ${argv}`);
  });
  
} else {
  // Using as a module
  module.exports = ...;
}

Now your application app.js can be launched from CLI as follows:

$ echo "your input" | app.js --yourOption 5 --nested.option "five"
$ app.js "your input" --yourOption 5 --nested.option "five"