Persey

gem "persey", '>= 1.0.0'

# Rails.root are not initialized here
app_path = File.expand_path('../../', __FILE__)

# your redis config
redis_config = File.join(app_path, 'config', 'redis.yml.example')

# your project config
# as example - it's default options from opensource
# you don't want redeclare then with copy default file
project_config = File.join(app_path, 'config', 'project.yml.example')

# some different environment specifed configuration options in separate config
project_env_config = File.join(app_path, 'config', "project.#{Rails.env}.yml")

# config for awesome gem
awesome_gem_config = File.join(app_path, 'config', 'awesome_gem_config.yml')

# config with secret keys
# you don't want store this config in repository and copy to secret folder on host machine
my_secret_key_config = '/home/user/secret/keys.yml'

# We support not only YAML
# Also JSON
my_node_js_config = '/rest/u/apps/node/config.json'
# And TOML
my_berkshelf_config = File.join(app_path, 'provisioning', '.berkshelf')
# And INI
my_ini_config = File.join(app_path, 'provisioning', 'php.ini') # lol

# Persey.init ENV["environment"] do # set current environment
Persey.init Rails.env do # set current environment
  source :yaml, redis_config,         :redis              # set specific namespace for settings (mount config in :redis key)
  source :yaml, project_config                            # if project config and project_env_config have some options keys
  source :yaml, project_env_config                        # last declared keys overwite before declared
  source :yaml, awesome_gem_config,   :awesome_gem        # it's good to mount unknown configs to special :namespace
  source :yaml, my_secret_key_config, :secret             # no comments. It's secret!
  source :json, my_node_js_config,    :node_js_namespace
  source :toml, my_berkshelf_config,  :berkshelf_namespace
  source :ini,  my_ini_config,        :ini_namespace

  env :production do
    site_name 'Example'
    web do
      # domain   'example.com'   # domain described in project_env_config
                                 # you can use them, or overwirite here
      protocol 'https'           # we overwrite prolocol option here
                                 # by default was 'http', but we need some little security
      port      12345            # more, more security!
      # and now we use configs for our options, which are not declared in any config
      uri      -> { "#{protocol}://#{domain}:#{port}" }
    end

    site_uri   -> { web.uri }    # we can re-re-use different options

    email do
      pop do
        address 'pop.example.com'
        port    110
      end
      smtp do
        address 'smtp.example.com'
        port    25
      end
    end
  end

  env :development, :parent => :production do
    web do
      domain   'localhost'
      protocol 'http'
      port      9292
    end
    email do
      smtp do
        address 'smpt.text.example.com'
      end
    end
  end
end

#...
# We require gem here
require "persey"
require File.expand_path('../config', __FILE__)

module AppName
  # If you don't want use configs with call Persey.config
  # you can do something like it:
  def self.config
    Persey.config
  end

  class Application < Rails::Application
    # ...
  end
end

config = Persey.config

config.site_name      # => 'Example'
config.web.uri        # => 'https://example.com:80'
config.site_uri       # => 'https://example.com:80'
config.email.pop.port # => 110

AppName.config.site_name # => 'Example'

Persey.init Rails.env do
  # settings
end

# config/environments/development.rb
ActionDispatch::Reloader.to_prepare do
  load Rails.root.join('config/config.rb')
end