Saicheg · September 19, 2013 07:59 · Feb 28, 2012 · Feb 15, 2011
diff --git a/xml_parser.rb b/xml_parser.rb
@@ -68,6 +68,7 @@ def for_element(name, &block)
     end
 
     def inside_element(name=nil, &block)
+      return if @node.self_closing?
       return unless name.nil? or (self.name == name and is_start?)
 
       name = @node.name

diff --git a/xml_parser.rb b/xml_parser.rb
@@ -0,0 +1,82 @@
+# A small DSL for helping parsing documents using Nokogiri::XML::Reader. The
+# XML Reader is a good way to move a cursor through a (large) XML document fast,
+# but is not as cumbersome as writing a full SAX document handler. Read about
+# it here: http://nokogiri.org/Nokogiri/XML/Reader.html
+# 
+# Just pass the reader in this parser and specificy the nodes that you are interested
+# in in a block. You can just parse every node or only look inside certain nodes.
+# 
+# A small example:
+# 
+# Xml::Parser.new(Nokogiri::XML::Reader(open(file))) do
+#   inside_element 'User' do
+#     for_element 'Name' do puts "Username: #{inner_xml}" end
+#     for_element 'Email' do puts "Email: #{inner_xml}" end
+#     
+#     for_element 'Address' do
+#       puts 'Start of address:'
+#       inside_element do
+#         for_element 'Street' do puts "Street: #{inner_xml}" end
+#         for_element 'Zipcode' do puts "Zipcode: #{inner_xml}" end
+#         for_element 'City' do puts "City: #{inner_xml}" end
+#       end
+#       puts 'End of address'
+#     end
+#   end
+# end
+# 
+# It does NOT fail on missing tags, and does not guarantee order of execution. It parses
+# every tag regardless of nesting. The only way to guarantee scope is by using
+# the `inside_element` method. This limits the parsing to the current or the named tag.
+# If tags are encountered multiple times, their blocks will be called multiple times.
+
+
+require 'nokogiri'
+
+module Xml
+  class Parser
+    def initialize(node, &block)
+      @node = node
+      @node.each do
+        self.instance_eval &block
+      end
+    end
+
+    def name
+      @node.name
+    end
+
+    def inner_xml
+      @node.inner_xml.strip
+    end
+
+    def is_start?
+      @node.node_type == Nokogiri::XML::Reader::TYPE_ELEMENT
+    end
+
+    def is_end?
+      @node.node_type == Nokogiri::XML::Reader::TYPE_END_ELEMENT
+    end
+
+    def attribute(attribute)
+      @node.attribute(attribute)
+    end
+
+    def for_element(name, &block)
+      return unless self.name == name and is_start?
+      self.instance_eval &block
+    end
+
+    def inside_element(name=nil, &block)
+      return unless name.nil? or (self.name == name and is_start?)
+
+      name = @node.name
+      depth = @node.depth
+
+      @node.each do
+        return if self.name == name and is_end? and @node.depth == depth
+        self.instance_eval &block
+      end
+    end
+  end
+end