README

Path: README
Last Update: Wed Aug 29 15:39:26 -0400 2007

INSTALLATION

Installation is simple. Follow the following steps:

Rubygems

  gem install libxml-ruby

Tarball/zip

  $ rake test
  $ rake install

If extconf yacks up an error, follow the instructions it provides. You will need to chdir to ext/xml and run ‘ruby extconf.rb’ to provide options, after which you can either use Rake for everything or do with make (make && make install).

Once installed, look at the test scripts (tests/*.rb), and run ‘rake doc’ to generate API documentation. You can find the latest documentation at:

DEPENDENCIES

libxml requires a few other libraries to be installed inorder to function properly.

  • libm (math routines: very standard)
  • libz (zlib)
  • libiconv
  • libxml2

USAGE

Basic usage for reading and writing documents.

WRITING

Writing a simple document: 

  # require 'rubygems' # if installed via Gems
        require 'xml/libxml'

        doc = XML::Document.new()
        doc.root = XML::Node.new('root_node')
        root = doc.root

        root << elem1 = XML::Node.new('elem1')
        elem1['attr1'] = 'val1'
        elem1['attr2'] = 'val2'

        root << elem2 = XML::Node.new('elem2')
        elem2['attr1'] = 'val1'
        elem2['attr2'] = 'val2'

        root << elem3 = XML::Node.new('elem3')
        elem3 << elem4 = XML::Node.new('elem4')
        elem3 << elem5 = XML::Node.new('elem5')

        elem5 << elem6 = XML::Node.new('elem6')
        elem6 << 'Content for element 6'

        elem3['attr'] = 'baz'

        # Namespace hack to reduce the numer of times XML:: is typed
        include XML
        root << elem7 = Node.new('foo')
        1.upto(10) do |i|
          elem7 << n = Node.new('bar')
          n << i
        end

        format = true
        doc.save('output.xml', format)

The file output.xml contains: 

        <?xml version="1.0"?>
        <root_node>
          <elem1 attr1="val1" attr2="val2"/>
          <elem2 attr1="val1" attr2="val2"/>
          <elem3 attr="baz">
            <elem4/>
            <elem5>
              <elem6>Content for element 6</elem6>
            </elem5>
          </elem3>
          <foo>
            <bar>1</bar>
            <bar>2</bar>
            <bar>3</bar>
            <bar>4</bar>
            <bar>5</bar>
            <bar>6</bar>
            <bar>7</bar>
            <bar>8</bar>
            <bar>9</bar>
            <bar>10</bar>
          </foo>
        </root_node>

READING

Reading XML is slightly more complex and there are many more ways to perform this operation. This reads in and processes the above generated XML document, output.xml. This script assumes that the structure of the document is already known. 

  # require 'rubygems' # if installed via Gems
        require 'xml/libxml'
        doc = XML::Document.file('output.xml')
        root = doc.root

        puts "Root element name: #{root.name}"

        elem3 = root.find('elem3').to_a.first
        puts "Elem3: #{elem3['attr']}"

        doc.find('//root_node/foo/bar').each do |node|
          puts "Node path: #{node.path} \t Contents: #{node.content}"
        end

And your terminal should look like: 

        Root element name: root_node
        Elem3: baz
        Node path: /root_node/foo/bar[1]         Contents: 1
        Node path: /root_node/foo/bar[2]         Contents: 2
        Node path: /root_node/foo/bar[3]         Contents: 3
        Node path: /root_node/foo/bar[4]         Contents: 4
        Node path: /root_node/foo/bar[5]         Contents: 5
        Node path: /root_node/foo/bar[6]         Contents: 6
        Node path: /root_node/foo/bar[7]         Contents: 7
        Node path: /root_node/foo/bar[8]         Contents: 8
        Node path: /root_node/foo/bar[9]         Contents: 9
        Node path: /root_node/foo/bar[10]        Contents: 10

MORE INFORMATION

If you have any questions, please send email to libxml-devel@rubyforge.org.

# $Id: README 143 2007-08-29 21:45:48Z transami $

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