Common OWL/RDFS Vocabularies for use with Ruby RDF.rb

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This gem extends RDF::Vocabulary with #to_ttl, #to_jsonld, and #to_html methods to create special-purpose vocabulary serializations. The HTML version is templated using a Haml template to allow output to be customized.

Also extends RDF::Vocabulary::Format with the gen-vocab command extension to the rdf executable.



Add to your Gemfile

gem "rdf-vocab"


bundle install


require "rdf/vocab"

This will load all the vocabulary classes in the library.

Also adds the gen-vocab command to the rdf command-line executable to generate specifically generated output in Turtle, JSON-LD, and HTML+RDFa for either built-in or arbitrary vocabularies.

Adding new vocabularies

  • First, add an entry to lib/rdf/vocab.rb, the key names contained within for guidance. For more information, see the documentation on RDF::Vocabulary.
  • Next, create an empty file in lib/rdf/vocab based on the key name for your vocabulary. For example, if you've added the vocabulary :foo, create a new empty file at lib/rdf/vocab/foo.rb.
  • Run rake gen_vocabs.



This repository uses Git Flow to mange development and release activity. All submissions must be on a feature branch based on the develop branch to ease staging and integration.

  • Do your best to adhere to the existing coding conventions and idioms.
  • Don't use hard tabs, and don't leave trailing whitespace on any line. Before committing, run git diff --check to make sure of this.
  • Do document every method you add using YARD annotations. Read the tutorial or just look at the existing code for examples.
  • Don't touch the .gemspec or VERSION files. If you need to change them, do so on your private branch only.
  • Do note that in order for us to merge any non-trivial changes (as a rule of thumb, additions larger than about 15 lines of code), we need an explicit public domain dedication on record from you.


This is free and unencumbered public domain software. For more information, see http://unlicense.org/ or the accompanying LICENSE file.