Puppet data to XML

examples-test.pp

$data = {
  '?xml version="1.0" encoding="UTF-8"?' => false,
  'xml' => {
    'fruit' => 'apple',
    'vegetables' => {
      'green' => 'cucumber',
      'brown' => 'potato'
    },
    'nested' => {
      'one' => {
        'foo' => 'bar',
      },
      'two' => {
        'foo' => 'bar',
      }
    }
  }
}

file { '/tmp/example.xml':
  ensure  => file,
  content => hash_to_xml($data),
}
file { '/tmp/example2.xml':
  ensure  => file,
  content => hash_to_xml($data, 0, "\t", 4),
}

lib-puppet-functions-hash_to_xml.rb

Puppet::Functions.create_function(:hash_to_xml) do
  dispatch :hash_to_xml do
    param 'Hash', :data
    optional_param 'Integer', :level
    optional_param 'String', :character
    optional_param 'Integer', :num
  end

  def calc_indent(level)
    @character * @num * level
  end

  def kv_to_xml(k, v = nil, level = 0, open = true, close = true)
    output = ''
    output += calc_indent(level)
    output +="<#{k}>" if open
    output += v if (open and close)
    output += "</#{k}>" if close
    output += "\n"
  end

  def hash_to_xml(h, level = 0, character = "\s", num = 2)
    @character             = character
    @num                   = num
    xml                    = ''
    h.each do |key, value|
      case value
      when String
        xml += kv_to_xml(key, value, level)
      when Hash
        xml += kv_to_xml(key, nil, level, true, false)
        xml += hash_to_xml(value, level+1, @character, @num)
        xml += kv_to_xml(key, nil, level, false, true)
      when FalseClass
        xml += kv_to_xml(key, nil, level, true, false)
      else
        fail('Error')
      end
    end
    return xml
  end
end

puppet.sh

[root@puppet /opt/puppetlabs/puppet/modules/hash_to_xml]# puppet apply examples/test.pp && cat /tmp/example.xml && cat /tmp/example2.xml
Notice: Compiled catalog for puppet.puppetlabs.vm in environment production in 0.08 seconds
Notice: Applied catalog in 0.25 seconds
<?xml version="1.0" encoding="UTF-8"?>
<xml>
  <fruit>apple</fruit>
  <vegetables>
    <green>cucumber</green>
    <brown>potato</brown>
  </vegetables>
  <nested>
    <one>
      <foo>bar</foo>
    </one>
    <two>
      <foo>bar</foo>
    </two>
  </nested>
</xml>
<?xml version="1.0" encoding="UTF-8"?>
<xml>
				<fruit>apple</fruit>
				<vegetables>
								<green>cucumber</green>
								<brown>potato</brown>
				</vegetables>
				<nested>
								<one>
												<foo>bar</foo>
								</one>
								<two>
												<foo>bar</foo>
								</two>
				</nested>
</xml>