URN 
Ruby library to validate and normalize URNs according to RFC 2141.
Supported Ruby versions: >= 2.3
Installation
Add this line to your application's Gemfile:
gem 'urn', '~> 2.0'And then execute:
$ bundle
Or install it yourself as:
$ gem install urn -v '~> 2.0'
Usage
urn = URN('URN:NameSpace:Identifier')
#=> #<URN:0x007fd97a835558 @urn="URN:NameSpace:Identifier">
urn = URN.new('URN:NameSpace:Identifier')
#=> #<URN:0x007fd97a835558 @urn="URN:NameSpace:Identifier">
urn.normalize
#=> "urn:namespace:Identifier"
urn = URN('123')
#=> URN::InvalidURNError: bad URN(is not URN?): 123API Documentation
URN::PATTERN
text.match(/\?urn=(#{URN::PATTERN})/)Return a String of an unanchored regular expression suitable for matching URNs.
URN::REGEX
URN::REGEX
#=> /\A(?i:urn:(?!urn:)[a-z0-9][a-z0-9-]{1,31}:(?:[a-z0-9()+,-.:=@;$_!*']|%[0-9a-f]{2})+)\z/Return a Regexp object with the anchored regular expression suitable to match a URN.
URN() or URN.new
urn = URN('urn:nid:nss')
#=> #<URN:0xdecafbad @urn="urn:nid:nss">
urn = URN.new('urn:nid:nss')
#=> #<URN:0xdecafbad @urn="urn:nid:nss">
urn = URN('1234')
#=> URN::InvalidURNError: bad URN(is not URN?): 1234Return a new URN instance when the given string is valid according to RFC 2141. Otherwise, it raises an URN::InvalidURNError
URN#normalize
URN('URN:FOO:BAR').normalize
#=> #<URN:0x007fb9a3096848 @urn="urn:foo:BAR">Return the normalized URN object, normalizing the case
of the urn token and namespace identifier. Call #to_s after #normalize if you want the normalized String representation.
URN#nid
URN('urn:nid:nss').nid
#=> "nid"Return the namespace identifier part.
URN#nss
URN('urn:nid:nss').nss
#=> "nss"Return the namespace specific string part.
URN#to_s
URN('urn:Nid:Nss').to_s
#=> "urn:Nid:Nss"Return the String representation.
#===(other)
URN('urn:name:spec') === 'URN:Name:spec'
#=> true
URN('urn:name:spec') === URN('URN:Name:spec')
#=> trueReturn true if the URN objects are equivalent. This method normalizes both URNs before doing the comparison, and allows comparison against Strings.
#==(other)
URN('urn:name:spec') == 'URN:Name:spec'
#=> false
URN('urn:name:spec') == URN('URN:Name:spec')
#=> trueReturns true if the URN objects are equivalent. This method normalizes both URNs before doing the comparison.
#eql?(other)
URN('urn:name:spec').eql?('urn:name:spec')
#=> false
URN('urn:name:spec').eql?(URN('urn:NAME:spec'))
#=> false
URN('urn:name:spec').eql?(URN('urn:name:spec'))
#=> trueReturns true if the URN objects are equal. This method does NOT normalize either URN before doing the comparison.
.extract(str)
URN.extract('text urn:1234:abc more text URN:foo:bar%23.\\')
#=> ['urn:1234:abc', 'URN:foo:bar%23.']
normalized_urns = []
#=> []
URN.extract('text urn:1234:abc more text URN:foo:bar%23.\\') { |urn| normalized_urns << URN(urn).normalize.to_s }
#=> nil
normalized_urns
#=> ['urn:1234:abc', 'URN:foo:bar%23.']Extracts URNs from a string. If block given, iterates through all matched URNs. Returns nil if block given or array with matches.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/altmetric/urn.
License
Copyright © 2016-2024 Altmetric LLP
Distributed under the MIT License.