config.rb in pione-0.1.1

- old
+ new
@@ -1,20 +1,68 @@
 module Pione
   module System
-    # Config represents a PIONE system configuration.
+    # Config is a class for setting PIONE system configuration.
     class Config < PioneObject
       extend Forwardable
 
-      attr_reader :path
+      # This exception class is raised when configuration file is in invalid format.
+      class InvalidConfigFormat < StandardError
+        # config file path
+        # @return [Pathname]
+        attr_reader :path
+
+        # Create an exception.
+        #
+        # @param path [Pathname]
+        #   configuration file path
+        def initialize(path)
+          @path = path
+        end
+
+        # @api private
+        def message
+          "invalid format configuration file: %s" % @path
+        end
+      end
+
+      class << self
+        # Load configuration and apply it to global settings.
+        #
+        # @param path [Pathname or String]
+        #   configuration file path
+        # @return [void]
+        def load(path)
+          new(path).tap {|x| x.apply}
+        end
+      end
+
       def_delegator :@table, "[]"
 
-      # Creates a new configuration.
-      # @param [Hash] data
-      #   preset configuration table
+      # config file path
+      # @return [Pathname]
+      attr_reader :path
+
+      # Create a new configuration.
+      #
+      # @param path [Pathname or String]
+      #   configuration file path
       def initialize(path)
         @path = Pathname.new(path)
         @table = @path.exist? ? YAML.load(@path.read) : {}
-        raise TypeError.new(@path) unless @table.kind_of?(Hash)
+        raise InvalidConfigFormat.new(@path) unless @table.kind_of?(Hash)
+      end
+
+      # Apply config date to global settings.
+      #
+      # @return [void]
+      def apply
+        # set values
+        keys = Global.all_names
+        @table.each do |key, val|
+          Global.send("set_%s" % key, val) if keys.include?(key.to_sym)
+        end
+        # initialize global settings with new configuration
+        Global.init
       end
     end
   end
 end