Global Names UUID

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Gem gn_uuid creates UUID version 5 out of scientific name string. It uses domain for DNS namespace. There is a 1:1 relationship between the string and the corresponding UUID, so it allows globally connect data about a name string originated from independent sources without a need to negotiate identifiers. You can find more information about UUID v5 from the original RFC4122 document.


Add this line to your application's Gemfile:

gem 'gn_uuid'

And then execute:

$ bundle

Or install it yourself as:

$ gem install gn_uuid


GnUUID.uuid(string, guid = true)

Parameter Type Description
str String Scientific Name String
guid Boolean true returns a String guid, false -- UUID object; default true
require "gn_uuid"

uuid = GnUUID.uuid("Homo sapiens")
# output: 16f235a0-e4a3-529c-9b83-bd15fe722110

If you plan to convert uuid into its other formats use

uuid = GnUUID.uuid("Homo sapiens", false)
# output: urn:uuid:b33e4b19-2399-56c8-9dd3-eff79f221d2f

# as a 'stanard guid'
# output: b33e4b19-2399-56c8-9dd3-eff79f221d2f

# as an decimal integer
# output: 30500639462008600581628158843502600464

# as an URI
uuid.inspect (alias_method for to_uri)
# output: urn:uuid:b33e4b19-2399-56c8-9dd3-eff79f221d2f

# as a 16-bytes string
# output: "\x16\xF25\xA0\xE4\xA3R\x9C\x9B\x83\xBD\x15\xFEr!\x10"

# return UUID version
# output: 5

Please note that the internal GnUUID::UUID does not have to be of the version 5, but GnUUID.uuid generates only version 5 UUIDs


Takes a uuid string like "b33e4b19-2399-56c8-9dd3-eff79f221d2f" and returns an instance of GnUUID::UUID class. It can parse any UUID, not only version 5

uuid = GnUUID.parse("b33e4b19-2399-56c8-9dd3-eff79f221d2f")
# output: urn:uuid:b33e4b19-2399-56c8-9dd3-eff79f221d2f


After checking out the repo, run bin/setup to install dependencies. Then, run rake rspec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to


Bug reports and pull requests are welcome on GitHub at


This gem heavily borrowed ideas and code from Urabe Shyouhei's ruby-uuid gem


The gem is available as open source under the terms of the MIT License.

Author -- Dmitry Mozzherin

Copyright (c) 2015 Marine Biological Laboratory.