Fig

DRY up those magic numbers and hard coded strings into something more managable. Fig is the smart way to manage stuff that really belongs in a config file instead of scattered throughout your code.

Why

I know that Ruby is a dynamic language and that hard coded values aren’t as big a deal, but… it’s still good practice to have a centralized place to hold certain settings.

I used to create a globally available Hash to store this stuff, but have always wanted something more powerful and elegant.

What

Fig is a simple to use configuration management tool for Ruby applications and libraries.

The primary features are:

Multiple configuration files
Dynamic updating and re-loading of configuration files
Simple dot-notation access to configuration settings
YAML access to configuration settings
Safe options to request settings that may not exist
Interpolation to help DRY up configuration files through reuse of settings
Thread safe

How

The simplest way to get started is to watch the 10 minute tutorial.

Installation

Fig is availabe as both a Gem and as a Rails Plugin.

To install as a Gem:

First, be sure that Github has been added as a gem source. (This only needs to be done once.)

gem sources -a http://gems.github.com

Second, install the Gem.

sudo gem install hopsoft-fig

To install as a Rails Plugin:

script/plugin install git://github.com/hopsoft/fig.git

Usage

Create a YAML file that will serve as one of the configuration files you plan to use. In a Rails application, I usually create the file config/app.yml, but you can name the file anything you like and can save it to any location within your appliation or library.

Require Fig either explicitly or implicitly. In a Rails application, I generally do this in environment.rb.

# implicit
require 'hopsoft/fig'
# explicit
gem 'hopsoft-fig'

Instantiate a Fig object that is globally available to your application. In a Rails application, I generally do this in environment.rb.

APP_CONFIG = Fig.new(RAILS_ROOT + '/config/app.yml')

Start using your settings.

puts APP_CONFIG.settings.message
puts APP_CONFIG.yaml['message']
puts APP_CONFIG.get_setting('message')
# returns nil instead of an error when the setting doesn't exist
puts APP_CONFIG.get_setting('some.nested.setting.that.may.not.exist')

Reuse settings in your YAML file (This is a great way to apply the DRY principle to your configuration settings):

name: Nathan Hopkins
message: {fig:name} says hello.

puts APP_CONFIG.get_setting('message')
# outputs -> Nathan Hopkins says hello.

Update the YAML file and load the changes without restarting your application.

APP_CONFIG.load