Strip invalid XML characters.

Author: hapiben

lib/oai/client.rb

@@ -251,6 +251,7 @@ def load_document(xml)
         end
       when 'rexml'
         begin
+          xml = strip_invalid_xml_chars(xml)
           return REXML::Document.new(xml)
         rescue REXML::ParseException => e
           raise OAI::Exception, 'response not well formed XML: '+e.message, caller
@@ -354,5 +355,18 @@ def strip_invalid_utf_8_chars(xml)
       xml
     end
 
+    def strip_invalid_xml_chars(xml)
+      invalid = false
+
+      begin
+        REXML::Document.new(xml)
+      rescue REXML::ParseException => e
+        invalid = true
+      end
+
+      return xml.gsub!(/&(?!(?:amp|lt|gt|quot|apos);)/, '&') if invalid
+      return xml
+    end
+
   end
 end