Settings

A special hash for application-wide settings.

Description

Small and simple specialized Hash which is helpful for storing immutable, required key/value pairs to be loaded from a YAML file.

New instances of Settings::Hash are readonly -- any attempt to write to the Hash after initialization will fail with a TypeError. This way you can avoid inadvertently altering the expected value of a setting at runtime.

Any attempt to read a key which is not set will raise a Settings::Hash::SettingNotFound error. This way expected values will raise when expected, making them easier to track down than if they had silently returned nil.

Settings::Hash supports an optional namespace which can be used to define multiple groups of settings within a single .yml file. Commonly this can be used to define per-environment settings, i.e. "test" and "development".

Finally, there is a small module which you can use in your Rack applications to provide some sensible defaults for loading a settings file.

Usage

config/settings.yml

test:
  :foo: 123456
development:
  :foo: "abcdef"

Settings::Hash:

settings = Settings::Hash.new("config/settings.yml")
settings["test"][:foo] #=> 123456
settings["development"][:foo] #=> "abcdef"

settings = Settings::Hash.new("config/settings.yml", "test")
settings[:foo] #=> 123456

ENV["RACK_ENV"] = "development"
settings = Settings::Hash.new("config/settings.yml", ENV["RACK_ENV"])
settings[:foo] #=> "abcdef"

Cuba:

Cuba.send :extend, Settings

Cuba.define do
  on "/" do
    res.write Cuba.setting(:foo) #=> "abcdef"
  end
end

Sinatra:

class MyApplication < Sinatra::Base
  extend Settings

  get "/" do
    MyApplication.setting(:foo) #=> "abcdef"
  end
end

Rails:

gem "settings", "0.0.4" # (in `Gemfile`)

Rails.send :extend, Settings # (in `config/initializers/settings.rb`)

class WidgetController < ActionController::Base
  def index
    Rails.setting("foo") #=> "abcdef"
  end
end

Installation

$ sudo gem install settings

Test

$ rake

Changelog

0.0.4

Settings no longer symbolizes keys. If you want to use symbols for keys, define your keys as symbols in your .yml file, i.e.:

:test:
  :alphabet: "abcdef"

instead of:

test:
  alphabet: "abcdef"

Settings no longer explicitly supports Rails -- instead it comes with some defaults for Rack applications which could be used with Rails.

License

Copyright (c) 2009-2011 Ben Alavi for Citrusbyte

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.