ConfigNewton

A common pattern for Ruby libraries is to have some kind of configuration that can be set at the library level. ConfigNewton is a simple library that provides a user-friendly way to expose that configuration.

Installation

gem install config_newton

Usage

require 'config_newton'

# The library author sets it up like this:

module MyLibrary
  include ConfigNewton

  config :email
  config :special_sauce, :default => true
end

# And the end user can set it like this:

MyLibrary.configure do |config|
  config.email = '[email protected]'
  config.special_sauce = false
end

# And the library author can use it like this:

module MyLibrary
  class Client
    # ... somewhere in the code ...
    MyLibrary.config.email # => '[email protected]'
  end
end

Other Useful Bits

There are a few other useful features of ConfigNewton. For instance, you can convert the configuration to a hash at any time, or just access it like one:

MyLibrary.config.to_hash # => {:email => '[email protected]', :special_sauce => false}
MyLibrary.config[:special_sauce] # => false

You can also load user settings from a YAML file quite easily. Let’s say you’re developing a Rails plugin. You can easily load a config directory YAML file like this:

MyLibrary.config.load_from("#{Rails.root}/config/my_library.yml", Rails.env)

The second argument specified is the “root key” for the configuration, allowing you to easily specify environments or other conditions. Using our examples above the user would create a YAML file in config/my_library.yml and populate it like this:

development:
  email: [email protected]
  special_sauce: false

production
  email: [email protected]
  special_sauce: true

Roadmap

There’s still further I’d like to take this library, here are a few thoughts:

Hierarchical Configuration: Create multi-level configurations that retain an intuitive interface both for the library developer and the user.
Typed Configurations: Implement a simple casting system to automatically convert values into desired types.

Note on Patches/Pull Requests