btrconf

Better (read: simpler) node.js config loader.

While there are other node.js config loaders out there, they force you to split your config into separate files. A default config file and then another per environment. For a small application (or microservice) it's often overkill to have your config spread across 3-5 different files.

btrconf is of the opinion that, for small projects, one config file is not just sufficient, but better. If you find your config file getting too large, split it into multiple files by configuration type (eg. database config, external service auth, etc.).

Usage

btrconf uses the NODE_ENV environment variable to determine which config it should load (default: 'development').

Given a config file ./config.js:

var env = process.env;
module.exports = {
  default: {
    port: env.PORT || 8080,
    errors: env.DISPLAY_ERRORS || true,
    db: {
      client: 'pg'
    }
  },
  test: {
    db: {
      connection: 'postgres://localhost:5432/testdb'
    }
  },
  development: {
    db: {
      connection: 'postgres://localhost:5432/devdb'
    }
  },
  production: {
    db: {
      connection: env.DB_URI,
    },
    errors: false
  }
}

You might have a server.js that looks something like:

var btrconf = require('btrconf');
var express = require('express');
var knex = require('knex');
 
var config = btrconf.load('./config');
var db = knex(config.db);
var server = express();
 
/* Set up your routes, etc. */
 
server.listen(config.port);

Typescript

This module comes with it's own (tiny) type definitions. The only real difference when you're using Typescript is that you'll need an interface that describes the structure of your config file.

To load the config file in the example above, your Typescript would look something like:

import * as btrconf from 'btrconf';
 
interface AppConfig {
  port: number;
  errors: boolean;
  db: {
    client: string;
    connection: string;
  };
}
 
let config = btrconf.load<AppConfig>('./config');
/* ... */

At the moment, there is no guarantee that the object is read from your config file matches your interface. If this is something you're interested in, raise an issue as I have a solution for this; I just haven't had time to implement it.

Caveats

Hey, we said it was better, not perfect ;)

Requiring btrconf from multiple files.

Since we're requiring files relative to your module, from all the way down in your node_modules/, we use module.parent.filename to determine the name of the file you are requiring btrconf from. We then load the specified config file relative to your that file.

This means that if you require('btrconf') from multiple files, module.parent.filename will refer to the first file to require btrconf. In this case, you can pass an absolute filename using:

var config = btrconf.load(require.resolve('./config'));

Due to the above, btrconf is currently not suitable for use in other npm modules, sorry!