ruby-configuration.rb

module Configuration
  Error = Class.new StandardError
  class << self

    def config(&block)
      @config ||= initialize_config
      block_given? and yield @config
      @config
    end

    def initialize_config
      _config = OpenStruct.new
    end

    def config=(config)
      @config = config
    end
  end
end

# project directory and name
Configuration.config.app_root = File.expand_path( File.dirname(__FILE__) + '/..' )
Configuration.config.app_name = Configuration.config.app_root.split('/')[-1]

# loading database
require_relative '../config/database'
Configuration.config.database = Sequel.connect(Configuration.config.database_url)

########################################################################################
# config/database.rb
########################################################################################
Configuration.config do |config|
  config.database_url = "sqlite:///#{config.app_root}/db/development.sqlite3"
end