Class: Tilia::Xml::Element::XmlFragment

Inherits:
Object
  • Object
show all
Includes:
Tilia::Xml::Element
Defined in:
lib/tilia/xml/element/xml_fragment.rb

Overview

The XmlFragment element allows you to extract a portion of your xml tree, and get a well-formed xml string.

This goes a bit beyond ‘innerXml` and friends, as we’ll also match all the correct namespaces.

Please note that the XML fragment:

  1. Will not have an <?xml declaration.

  2. Or a DTD

  3. It will have all the relevant xmlns attributes.

  4. It may not have a root element.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from XmlDeserializable

#xml_deserialize

Constructor Details

#initialize(xml) ⇒ XmlFragment

Returns a new instance of XmlFragment.



19
20
21
 
# File 'lib/tilia/xml/element/xml_fragment.rb', line 19

def initialize(xml)
  @xml = xml
end

Instance Attribute Details

#xml ⇒ Object (readonly)

Returns the value of attribute xml.



23
24
25
 
# File 'lib/tilia/xml/element/xml_fragment.rb', line 23

def xml
  @xml
end

Class Method Details

.xml_deserialize(reader) ⇒ Object

The deserialize method is called during xml parsing.

This method is called statictlly, this is because in theory this method may be used as a type of constructor, or factory method.

Often you want to return an instance of the current class, but you are free to return other data as well.

You are responsible for advancing the reader to the next element. Not doing anything will result in a never-ending loop.

If you just want to skip parsing for this element altogether, you can just call $reader->next();

$reader->parseInnerTree() will parse the entire sub-tree, and advance to the next element.

Parameters:

Returns:

  • (Object) 


71
72
73
74
75
 
# File 'lib/tilia/xml/element/xml_fragment.rb', line 71

def self.xml_deserialize(reader)
  result = new(reader.read_inner_xml)
  reader.next
  result
end

Instance Method Details

#==(other) ⇒ Object

TODO: document



78
79
80
81
82
83
84
 
# File 'lib/tilia/xml/element/xml_fragment.rb', line 78

def ==(other)
  if other.is_a? self.class
    other.xml == @xml
  else
    false
  end
end

#xml_serialize(writer) ⇒ void

This method returns an undefined value.

The xmlSerialize method is called during xml writing.

Use the $writer argument to write its own xml serialization.

An important note: do not create a parent element. Any element implementing XmlSerializble should only ever write what’s considered its ‘inner xml’.

The parent of the current element is responsible for writing a containing element.

This allows serializers to be re-used for different element names.

If you are opening new elements, you must also close them again.

Parameters:



26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
 
# File 'lib/tilia/xml/element/xml_fragment.rb', line 26

def xml_serialize(writer)
  reader = Reader.new

  # Wrapping the xml in a container, so root-less values can still be
  # parsed.
  xml = <<XML
<?xml version="1.0"?>
<xml-fragment xmlns="http://sabre.io/ns">#{@xml}</xml-fragment>
XML

  reader.xml(xml)

  while reader.read
    if reader.depth < 1
      # Skipping the root node.
      next
    end

    case reader.node_type
    when ::LibXML::XML::Reader::TYPE_ELEMENT
      writer.start_element(reader.clark)
      empty = reader.empty_element?

      while reader.move_to_next_attribute != 0
        case reader.namespace_uri
        when '', nil # RUBY namespace_uri = nil ...
          writer.write_attribute(reader.local_name, reader.value)
        when 'http://www.w3.org/2000/xmlns/'
          # Skip namespace declarations
        else
          writer.write_attribute(reader.clark, reader.value)
        end
      end

      writer.end_element if empty
    when ::LibXML::XML::Reader::TYPE_CDATA,
        ::LibXML::XML::Reader::TYPE_TEXT
      writer.write_string(reader.value)
    when ::LibXML::XML::Reader::TYPE_END_ELEMENT
      writer.end_element
    end
  end
end