add JRuby-JDOM backend for XmlMini

Signed-off-by: Jeremy Kemper <jeremy@bitsweat.net>

2 files changed, 315 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/xml_mini/jdom.rb b/activesupport/lib/active_support/xml_mini/jdom.rb
new file mode 100644
index 0000000000..d795d55690
--- /dev/null
+++ b/activesupport/lib/active_support/xml_mini/jdom.rb
@@ -0,0 +1,162 @@
+raise "JRuby is required to use the JDOM backend for XmlMini" unless RUBY_PLATFORM =~ /java/
+
+require 'jruby'
+include Java
+
+import javax.xml.parsers.DocumentBuilder unless defined? DocumentBuilder
+import javax.xml.parsers.DocumentBuilderFactory unless defined? DocumentBuilderFactory
+import java.io.StringReader unless defined? StringReader
+import org.xml.sax.InputSource unless defined? InputSource
+import org.xml.sax.Attributes unless defined? Attributes
+import org.w3c.dom.Node unless defined? Node
+
+# = XmlMini JRuby JDOM implementation
+module ActiveSupport
+  module XmlMini_JDOM #:nodoc:
+    extend self
+
+    CONTENT_KEY = '__content__'.freeze
+
+    NODE_TYPE_NAMES = %w{ATTRIBUTE_NODE CDATA_SECTION_NODE COMMENT_NODE DOCUMENT_FRAGMENT_NODE
+    DOCUMENT_NODE DOCUMENT_TYPE_NODE ELEMENT_NODE ENTITY_NODE ENTITY_REFERENCE_NODE NOTATION_NODE
+    PROCESSING_INSTRUCTION_NODE TEXT_NODE}
+
+    node_type_map = {}
+    NODE_TYPE_NAMES.each { |type| node_type_map[Node.send(type)] = type }
+
+    # Parse an XML Document string into a simple hash using Java's jdom.
+    # string::
+    #   XML Document string to parse
+    def parse(string)
+      if string.blank?
+        {}
+      else
+        @dbf = DocumentBuilderFactory.new_instance
+        xml_string_reader = StringReader.new(string)
+        xml_input_source = InputSource.new(xml_string_reader)
+        doc = @dbf.new_document_builder.parse(xml_input_source)
+        merge_element!({}, doc.document_element)
+      end
+    end
+
+    private
+
+    # Convert an XML element and merge into the hash
+    #
+    # hash::
+    #   Hash to merge the converted element into.
+    # element::
+    #   XML element to merge into hash
+    def merge_element!(hash, element)
+      merge!(hash, element.tag_name, collapse(element))
+    end
+
+    # Actually converts an XML document element into a data structure.
+    #
+    # element::
+    #   The document element to be collapsed.
+    def collapse(element)
+      hash = get_attributes(element)
+
+      child_nodes = element.child_nodes
+      if child_nodes.length > 0
+        for i in 0...child_nodes.length
+          child = child_nodes.item(i)
+          merge_element!(hash, child) unless child.node_type == Node.TEXT_NODE
+        end
+        merge_texts!(hash, element) unless empty_content?(element)
+        hash
+      else
+        merge_texts!(hash, element)
+      end
+    end
+
+    # Merge all the texts of an element into the hash
+    #
+    # hash::
+    #   Hash to add the converted emement to.
+    # element::
+    #   XML element whose texts are to me merged into the hash
+    def merge_texts!(hash, element)
+      text_children = texts(element)
+      if text_children.join.empty?
+        hash
+      else
+        # must use value to prevent double-escaping
+        merge!(hash, CONTENT_KEY, text_children.join)
+      end
+    end
+
+    # Adds a new key/value pair to an existing Hash. If the key to be added
+    # already exists and the existing value associated with key is not
+    # an Array, it will be wrapped in an Array. Then the new value is
+    # appended to that Array.
+    #
+    # hash::
+    #   Hash to add key/value pair to.
+    # key::
+    #   Key to be added.
+    # value::
+    #   Value to be associated with key.
+    def merge!(hash, key, value)
+      if hash.has_key?(key)
+        if hash[key].instance_of?(Array)
+          hash[key] << value
+        else
+          hash[key] = [hash[key], value]
+        end
+      elsif value.instance_of?(Array)
+        hash[key] = [value]
+      else
+        hash[key] = value
+      end
+      hash
+    end
+
+    # Converts the attributes array of an XML element into a hash.
+    # Returns an empty Hash if node has no attributes.
+    #
+    # element::
+    #   XML element to extract attributes from.
+    def get_attributes(element)
+      attribute_hash = {}
+      attributes = element.attributes
+      for i in 0...attributes.length
+         attribute_hash[attributes.item(i).name] =  attributes.item(i).value
+       end
+      attribute_hash
+    end
+
+    # Determines if a document element has text content
+    #
+    # element::
+    #   XML element to be checked.
+    def texts(element)
+      texts = []
+      child_nodes = element.child_nodes
+      for i in 0...child_nodes.length
+        item = child_nodes.item(i)
+        if item.node_type == Node.TEXT_NODE
+          texts << item.get_data
+        end
+      end
+      texts
+    end
+
+    # Determines if a document element has text content
+    #
+    # element::
+    #   XML element to be checked.
+    def empty_content?(element)
+      text = ''
+      child_nodes = element.child_nodes
+      for i in 0...child_nodes.length
+        item = child_nodes.item(i)
+        if item.node_type == Node.TEXT_NODE
+          text << item.get_data.strip
+        end
+      end
+      text.strip.length == 0
+    end
+  end
+end
diff --git a/activesupport/test/xml_mini/jdom_engine_test.rb b/activesupport/test/xml_mini/jdom_engine_test.rb
new file mode 100644
index 0000000000..b745228994
--- /dev/null
+++ b/activesupport/test/xml_mini/jdom_engine_test.rb
@@ -0,0 +1,153 @@
+require 'abstract_unit'
+require 'active_support/xml_mini'
+
+if RUBY_PLATFORM =~ /java/
+
+class JDOMEngineTest < Test::Unit::TestCase
+  include ActiveSupport
+
+  def setup
+    @default_backend = XmlMini.backend
+    XmlMini.backend = 'JDOM'
+  end
+
+  def teardown
+    XmlMini.backend = @default_backend
+  end
+
+  # def test_file_from_xml
+  #   hash = Hash.from_xml(<<-eoxml)
+  #     <blog>
+  #       <logo type="file" name="logo.png" content_type="image/png">
+  #       </logo>
+  #     </blog>
+  #   eoxml
+  #   assert hash.has_key?('blog')
+  #   assert hash['blog'].has_key?('logo')
+  #
+  #   file = hash['blog']['logo']
+  #   assert_equal 'logo.png', file.original_filename
+  #   assert_equal 'image/png', file.content_type
+  # end
+
+  def test_exception_thrown_on_expansion_attack
+    assert_raise NativeException do
+      attack_xml = <<-EOT
+      <?xml version="1.0" encoding="UTF-8"?>
+      <!DOCTYPE member [
+        <!ENTITY a "&b;&b;&b;&b;&b;&b;&b;&b;&b;&b;">
+        <!ENTITY b "&c;&c;&c;&c;&c;&c;&c;&c;&c;&c;">
+        <!ENTITY c "&d;&d;&d;&d;&d;&d;&d;&d;&d;&d;">
+        <!ENTITY d "&e;&e;&e;&e;&e;&e;&e;&e;&e;&e;">
+        <!ENTITY e "&f;&f;&f;&f;&f;&f;&f;&f;&f;&f;">
+        <!ENTITY f "&g;&g;&g;&g;&g;&g;&g;&g;&g;&g;">
+        <!ENTITY g "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx">
+      ]>
+      <member>
+      &a;
+      </member>
+      EOT
+      Hash.from_xml(attack_xml)
+    end
+  end
+
+  def test_setting_JDOM_as_backend
+    XmlMini.backend = 'JDOM'
+    assert_equal XmlMini_JDOM, XmlMini.backend
+  end
+
+  def test_blank_returns_empty_hash
+    assert_equal({}, XmlMini.parse(nil))
+    assert_equal({}, XmlMini.parse(''))
+  end
+
+  def test_array_type_makes_an_array
+    assert_equal_rexml(<<-eoxml)
+      <blog>
+        <posts type="array">
+          <post>a post</post>
+          <post>another post</post>
+        </posts>
+      </blog>
+    eoxml
+  end
+
+  def test_one_node_document_as_hash
+    assert_equal_rexml(<<-eoxml)
+    <products/>
+    eoxml
+  end
+
+  def test_one_node_with_attributes_document_as_hash
+    assert_equal_rexml(<<-eoxml)
+    <products foo="bar"/>
+    eoxml
+  end
+
+  def test_products_node_with_book_node_as_hash
+    assert_equal_rexml(<<-eoxml)
+    <products>
+      <book name="awesome" id="12345" />
+    </products>
+    eoxml
+  end
+
+  def test_products_node_with_two_book_nodes_as_hash
+    assert_equal_rexml(<<-eoxml)
+    <products>
+      <book name="awesome" id="12345" />
+      <book name="america" id="67890" />
+    </products>
+    eoxml
+  end
+
+  def test_single_node_with_content_as_hash
+    assert_equal_rexml(<<-eoxml)
+      <products>
+        hello world
+      </products>
+    eoxml
+  end
+
+  def test_children_with_children
+    assert_equal_rexml(<<-eoxml)
+    <root>
+      <products>
+        <book name="america" id="67890" />
+      </products>
+    </root>
+    eoxml
+  end
+
+  def test_children_with_text
+    assert_equal_rexml(<<-eoxml)
+    <root>
+      <products>
+        hello everyone
+      </products>
+    </root>
+    eoxml
+  end
+
+  def test_children_with_non_adjacent_text
+    assert_equal_rexml(<<-eoxml)
+    <root>
+      good
+      <products>
+        hello everyone
+      </products>
+      morning
+    </root>
+    eoxml
+  end
+
+  private
+  def assert_equal_rexml(xml)
+    hash = XmlMini.with_backend('REXML') { XmlMini.parse(xml) }
+    assert_equal(hash, XmlMini.parse(xml))
+  end
+end
+
+else
+  # don't run these test because we aren't running in JRuby
+end