lib/ezid/metadata.rb in ezid-client-1.0.1 vs lib/ezid/metadata.rb in ezid-client-1.1.0

@@ -1,44 +1,56 @@
-require "delegate"
+require "forwardable"
 
 module Ezid
   #
   # EZID metadata collection for an identifier.
   #
   # @api private
   #
-  class Metadata < SimpleDelegator
+  class Metadata
+    extend Forwardable
+
+    attr_reader :elements
+
+    def_delegators :elements, :[], :[]=, :each, :clear, :to_h, :empty?
     
     class << self
-      def metadata_reader(method, alias_as=nil)
-        define_method method do
-          self[method.to_s]
+      def metadata_reader(element, alias_as=nil)
+        define_method element do
+          get(element)
         end
         if alias_as
-          alias_method alias_as, method
+          alias_method alias_as, element
         end
       end
 
-      def metadata_writer(method, alias_as=nil)
-        define_method "#{method}=" do |value|
-          self[method.to_s] = value
+      def metadata_writer(element, alias_as=nil)
+        define_method "#{element}=" do |value|
+          set(element, value)
         end
         if alias_as
-          alias_method "#{alias_as}=".to_sym, "#{method}=".to_sym
+          alias_method "#{alias_as}=".to_sym, "#{element}=".to_sym
         end 
       end
 
-      def metadata_accessor(method, alias_as=nil)
-        metadata_reader method, alias_as
-        metadata_writer method, alias_as
+      def metadata_accessor(element, alias_as=nil)
+        metadata_reader element, alias_as
+        metadata_writer element, alias_as
       end
 
-      def metadata_profile(profile, *methods)
-        methods.each do |method| 
-          element = [profile, method].join(".")
-          alias_as = [profile, method].join("_")
-          metadata_accessor element, alias_as
+      def metadata_profile(profile, *elements)
+        elements.each do |element| 
+          profile_element = [profile, element].join(".")
+          method = [profile, element].join("_")
+          
+          define_method method do
+            get(profile_element)
+          end
+
+          define_method "#{method}=" do |value|
+            set(profile_element, value)
+          end
         end
       end
     end
 
     # EZID metadata field/value separator
@@ -69,35 +81,47 @@
 
     # EZID reserved metadata elements that are read-only
     # @see http://ezid.cdlib.org/doc/apidoc.html#internal-metadata
     READONLY = %w( _owner _ownergroup _shadows _shadowedby _datacenter _created _updated )
 
+    # EZID metadata profiles - a hash of (profile => elements)
+    # @see http://ezid.cdlib.org/doc/apidoc.html#metadata-profiles
+    # @note crossref is not included because it is a simple element
+    PROFILES = {
+      dc: [:creator, :title, :publisher, :date, :type],
+      datacite: [:creator, :title, :publisher, :publicationyear, :resourcetype],
+      erc: [:who, :what, :when]
+    }
+    
+    PROFILES.each do |profile, elements|
+      metadata_profile profile, *elements 
+    end
+
+    # Accessors for EZID internal metadata elements
     metadata_accessor :_coowners, :coowners
     metadata_accessor :_crossref
     metadata_accessor :_export, :export
     metadata_accessor :_profile, :profile
     metadata_accessor :_status, :status
     metadata_accessor :_target, :target
 
-    metadata_accessor :crossref
-    metadata_accessor :datacite
-    metadata_accessor :erc
-
+    # Readers for EZID read-only internal metadata elements
     metadata_reader :_created 
     metadata_reader :_datacenter, :datacenter
     metadata_reader :_owner, :owner
     metadata_reader :_ownergroup, :ownergroup
     metadata_reader :_shadowedby, :shadowedby
     metadata_reader :_shadows, :shadows
     metadata_reader :_updated 
 
-    metadata_profile :dc, :creator, :title, :publisher, :date, :type
-    metadata_profile :datacite, :creator, :title, :publisher, :publicationyear, :resourcetype
-    metadata_profile :erc, :who, :what, :when
+    # Accessors for 
+    metadata_accessor :crossref
+    metadata_accessor :datacite
+    metadata_accessor :erc
 
     def initialize(data={})
-      super coerce(data)
+      @elements = coerce(data)
     end
 
     def created
       to_time _created
     end
@@ -108,20 +132,42 @@
 
     # Output metadata in EZID ANVL format
     # @see http://ezid.cdlib.org/doc/apidoc.html#request-response-bodies
     # @return [String] the ANVL output
     def to_anvl(include_readonly = true)
-      hsh = __getobj__.dup
+      hsh = elements.dup
       hsh.reject! { |k, v| READONLY.include?(k) } unless include_readonly
-      elements = hsh.map do |name, value| 
+      lines = hsh.map do |name, value| 
         element = [escape(ESCAPE_NAMES_RE, name), escape(ESCAPE_VALUES_RE, value)]
         element.join(ANVL_SEPARATOR)
       end
-      elements.join("\n").force_encoding(Encoding::UTF_8)
+      lines.join("\n").force_encoding(Encoding::UTF_8)
     end
 
+    def inspect
+      "#<#{self.class.name} elements=#{elements.inspect}>"
+    end
+
     def to_s
       to_anvl
+    end
+
+    def get(element)
+      self[element.to_s]
+    end
+
+    def set(element, value)
+      self[element.to_s] = value
+    end
+
+    protected
+
+    def method_missing(method, *args)
+      return get(method) if args.size == 0
+      if element = method.to_s[/^([^=]+)=$/, 1]
+        return set(element, *args)
+      end
+      super
     end
 
     private
 
     def to_time(value)