collate-config

A utility that climbs the directory tree looking for and optionally combining JSON config files specified in parent modules/projects.

This allows you to change how a dependency builds or behaves depending on config hosted in your importing project (similar to how .babelrc and similar files work)

Usage

import collateConfig from 'collate-config';

const config = collateConfig('.yourmodulerc');

In this example collate-config will, starting from its own root dir, climb up the directory tree looking for a directory containing BOTH a package.json and a .yourmodulerc file. If it finds one, it will parse the latter as JSON, Object.assign the result to a collection, and continue up the tree. If it encounters another valid config directory, the properties from that .yourmodulerc will override the ones specified earlier by default.

For example, with the following files and directory structure:

// ~/parent-project/node_modules/some-dependency/.yourmodulerc
{
  "a": "I've just been defined!",
  "b": "Hey me too!"
}

/* ... */

// ~/parent-project/.yourmodulerc
{
  "b": "I've just been overridden!",
  "c": "I'm new around here."
}

/* ... */

// ~/parent-project/node_modules/some-dependency/index.js

import collateConfig from 'collate-config';

const config = collateConfig('.yourmodulerc');
/*
  config = {
    "a": "I've just been defined!",
    "b": "I've just been overridden!",
    "c": "I'm new around here."
  }
*/

Sealing config to prevent unwanted overrides

By default collate-config will traverse up the entire directory tree until it hits the root. To prevent this behavior you can "seal" any particular config file by defining the __sealed property in its JSON object with any truthy value.

For example, if we made the following edit to our above example:

// ~/parent-project/node_modules/some-dependency/.yourmodulerc
{
  "__sealed": true,
  "a": "I've just been defined!",
  "b": "Hey me too!"
}

Then collate-config would stop after parsing this file and would NOT parse the .yourmodulerc file in parent-project's root. The final output would then be:

{
  "__sealed": true,
  "a": "I've just been defined!",
  "b": "Hey me too!"
}