record.rb in exlibris-aleph-1.0.0

- old
+ new
@@ -1,64 +1,58 @@
 module Exlibris
   module Aleph
+    require 'marc'
     # ==Overview
     # Provides access to the Aleph Record REST API.
-    class Record < Rest
-      attr_reader :bib_library, :record_id
+    class Record < Rest::Base
+      attr_accessor :bib_library, :record_id
 
-      # Creates an instance of Exlibris::Aleph::Record for the given :bib_library and :record_id
-      def initialize(bib_library, record_id, uri)
-        @record_id = record_id
-        raise "Initialization error in #{self.class}. Missing record id." if @record_id.nil?
-        @bib_library = bib_library
-        raise "Initialization error in #{self.class}. Missing bib library." if @bib_library.nil?
-        super(uri)
-        @uri = @uri+ "/record/#{bib_library}#{record_id}"
-        # Format :xml parses response as a hash.
-        # Eventually I'd like this to be the default since it raises exceptions for invalid XML.
-        # self.class.format :xml
-        # Format :html does no parsing, just passes back raw XML for parsing by client
-        self.class.format :html
+      def initialize(*args)
+        super
       end
 
-      # Returns an XML string representation of a bib.  
+      # Returns a MARC::Record that contains the bib data
       # Every method call refreshes the data from the underlying API.
-      # Raises and exception if there are errors.
-      # Returns a HTTParty::Response.
+      # Raises an exception if the response is not valid XML or there are errors.
       def bib
-        @response = self.class.get(@uri+ "?view=full")
-        raise "Error getting bib from Aleph REST APIs. #{error}" unless error.nil?
-        return @response
+        self.response = self.class.get("#{record_url}?view=full")
+        raise_error_if("Error getting bib from Aleph REST APIs.") {
+          (response.parsed_response["get_record"].nil? or response.parsed_response["get_record"]["record"].nil?)
+        }
+        MARC::XMLReader.new(StringIO.new(xml(xml: response.body).at_xpath("get-record/record").to_xml(xml_options).strip)).first
       end
 
-      # Returns an array of items. Each item is represented as an HTTParty hash. 
+      # Returns an array of items. Each item is represented as a Hash.
       # Every method call refreshes the data from the underlying API.
       # Raises an exception if the response is not valid XML or there are errors.
-      # Returns a HTTParty::Response.
       def items
-        @items = []
-        self.class.format :xml
         # Since we're parsing xml, this will raise an error
         # if the response isn't xml.
-        @response = self.class.get(@uri+ "/items?view=full")
-        self.class.format :html
-        raise "Error getting items from Aleph REST APIs. #{error}" if not error.nil? or 
-          @response.nil? or @response["get_item_list"].nil? or @response["get_item_list"]["items"].nil?
-        item_list = @response["get_item_list"]["items"]["item"]
-        @items.push(item_list) if item_list.instance_of?(Hash)
-        item_list.each {|item|@items.push(item)} if item_list.instance_of?(Array)
-        # Rails.logger.warn("No items returned from Aleph in #{self.class}.") if @items.empty?
-        return @items
+        self.response = self.class.get("#{record_url}/items?view=full")
+        raise_error_if("Error getting items from Aleph REST APIs.") {
+          (response.parsed_response["get_item_list"].nil? or response.parsed_response["get_item_list"]["items"].nil?)
+        }
+        [response.parsed_response["get_item_list"]["items"]["item"]].flatten
       end
 
-      # Returns an XML string representation of holdings 
+      # Returns an array of holdings. Each holding is represented as a MARC::Record.
       # Every method call refreshes the data from the underlying API.
-      # Raises and exception if there are errors.
-      # Returns a HTTParty::Response.
+      # Raises an exception if there are errors.
       def holdings
-        @response = self.class.get(@uri+ "/holdings?view=full")
-        raise "Error getting holdings from Aleph REST APIs. #{error}" unless error.nil?
-        return @response
+        self.response = self.class.get("#{record_url}/holdings?view=full")
+        raise_error_if("Error getting holdings from Aleph REST APIs.") {
+          (response.parsed_response["get_hol_list"].nil? or response.parsed_response["get_hol_list"]["holdings"].nil?)
+        }
+        xml(xml: response.body).xpath("get-hol-list/holdings/holding").collect{ |holding|
+          # Change the tag name to record so that the MARC::XMLReader can parse it.
+          holding.name = "record"
+          MARC::XMLReader.new(StringIO.new(holding.to_xml(xml_options).strip)).first
+        }
       end
+
+      def record_url
+        @record_url ||= "#{rest_url}/record/#{bib_library}#{record_id}"
+      end
+      private :record_url
     end
   end
 end
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