Nori

Really simple XML parsing ripped from Crack which ripped it from Merb.
Nori was created to bypass the stale development of Crack, improve its XML parser
and fix certain issues.

parser = Nori.new
parser.parse("<tag>This is the contents</tag>")
# => { 'tag' => 'This is the contents' }

Nori supports pluggable parsers and ships with both REXML and Nokogiri implementations.
It defaults to Nokogiri since v2.0.0, but you can change it to use REXML via:

Nori.new(:parser => :rexml)  # or :nokogiri

Make sure Nokogiri is in your LOAD_PATH when parsing XML, because Nori tries to load it
when it's needed.

Typecasting

Auto-Detection / Advanced Typecasting

Nori supports auto detection for text nodes without a defined type, beside the regular typecasting mechanism that uses the type attribute for conversion. This option is called :advanced_typecasting and can currently detect and cast:

• "true" and "false" values
• XMLSchema types: time, date, dateTime

It is enabled by default and must be disabled explicitly:

Nori.new(:advanced_typecasting => false)

see Nori::TypeConverter::Autodetect

Custom Type Conversion

Custom types can be converted easily with custom conversions.

E.g to convert a range of integers:

XML

<?xml version="1.0" encoding="UTF-8"?>
  <officeHours type="interval">8..17</officeHours>

Custom Conversion Class

class ToIntRange
  def self.convert(value)
    return nil if (value.nil? || value.length == 0)
    range = value.split('..')
    return range.first.to_i..range.last.to_i
  end
end

type_converter = Nori::TypeConverter.new('interval' => ToIntRange)
nori = Nori.new(:type_converter => type_converter)
nori.parse(xml)

Namespace Prefix Detection

Nori::TypeConverter does type conversion based on the type attribute. By default the namespace prefix for the type attribute and the type value is empty. In order to use a non-empty namespace prefix it provides builtin namespace detection for XMLSchema / XMLSchema-instance namespace:

  xml = request.body.read
  type_converter = Nori::DEFAULT_TYPE_CONVERTER.tap {|c| c.detect_namespace_prefixes!(xml)}
  nori = Nori.new(:type_converter => type_converter)

• You can also use custom namespaces - see TypeConverter spec

Namespaces

Nori can strip the namespaces from your XML tags. This feature might raise
problems and is therefore disabled by default. Enable it via:

Nori.new(:strip_namespaces => true)

XML tags -> Hash keys

Nori lets you specify a custom formula to convert XML tags to Hash keys.
Let me give you an example:

parser = Nori.new(:convert_tags_to => lambda { |tag| tag.snakecase.to_sym })

xml = '<userResponse><accountStatus>active</accountStatus></userResponse>'
parser.parse(xml)  # => { :user_response => { :account_status => "active" }