figs

Config inheritance & overriding

Figs—config management!

Provides config inheritance & overriding in a plethora of ways!

First of all, I want to say overriding will MERGE objects, not clobber the old one with the new one. Also, the following are listed from lowest precedence to highest.

This will allow you to inherit & override configs in parent directories.

This is useful if you want to share a config between multiple projects.

For example:

/home/subc/ringer.io/config.json

{"foo": "base", "bar": "meow"}

/home/subc/ringer.io/frontend/config.json

{"hello": "WORLD", "foo": "OVERRIDE"}

Result:

{"hello": "WORLD", "foo": "OVERRIDE", "bar": "meow"}

We'll next load any config.local.js and config.local.json configs! Inheritance also works with these local configs too.

This is useful if you want to override things in your repo without committing them.

/home/subc/ringer.io/frontend/config.json

{"foo": "bar"}

/home/subc/ringer.io/frontend/config.local.json

{"foo": "OVERRIDE"}

Result:

{"foo": "OVERRIDE"}

Finally, you can club children by creating a config.js or config.json in a parent directory. This works in the exact opposite of the config inheritance, think of it as seniority.

This is useful for when you're working on multiple projects, and you want to clobber all those mofos at once, and you're too lazy to use an environment variable.

For example:

/home/subc/ringer.io/frontend/config.json

{"ringer_www_domain": "ringer.io"}

/home/subc/clobber.json

{"ringer_www_domain": "localhost"}

Result:

{"ringer_www_domain": "localhost"}

You can also load a config by setting CONFIG="/home/subc/ringer.io-override.js" in your environment before starting the Node.js process.

This is useful for production, so we can specify production configurations.


You can override any property with a string by passing in a ENV variable which maps to a key in the object.

This is useful for production, if you're too lazy to add the override to a file.

To map a key to an ENV variable, replace . with __, and prepend it with CONFIG_.

Passing true, false will set booleans! Otherwise it will set the string you pass.

For example:

CONFIG_domain__ringer_www__host="dev.ringer.io.com"
CONFIG_debug="true"

Result:

{"domain": {"ringer_www": {"host": "dev.ringer.io.com"}},
 "debug": true}

To use the tool, install this library globally with NPM:

$ npm install -g figs
Use: figs [-opts] [directory]
 
Arguments:
  directory   inspect from the specified directory
 
Options:
  --help, -h  this message
  --list, -l  all configs in the inheritance chain
  --view, -v  full stack trace of all the configs & contents
  --json, -j  View the raw JSON

Require figs directly into your config variable.

// config.js 
exports.debug = true;
 
// app.js 
var config = require('figs');
 
console.log('Are we in debug mode?', config.debug);

Simply pass the config object into browserify, and this will build the state of your config into your browserify bundle at the time of compilation.

// bundling 
browserify.use(require('figs'));
 
// front-end 
var config = require('figs');

You can also call figs with an object to return a Browserify plugin mounting that as your config in the front end. This will wash your configuration to only include a subset of your configuration. Because I'm sure you have secret keys in your config.

var config = require('figs');
 
var bundle = browserify({
    // ... 
});
 
bundle.use(config({
    extra: 'config variables',
    domain: config.domain,
    fb: {
        app_id: config.fb.app_id,
        scope: config.fb.scope
        // We don't want our `fb.secret` in our front end! 
    }
}));

You can also use it from the browserify tool.

$ browserify --plugin figs

(The MIT License)

Copyright (c) 2012 Ryan Munro <ryan@subc.io>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.