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There was some discussion of this question here: http://stackoverflow.com/questions/931548/the-state-of-rdf-in-ruby where Dave Beckett notes that the Ruby bindings for his Redland library have not been updated for a while (though probably still work). Can anyone comment on whether the Ruby Redland bindings work correctly in recent versions of Ruby?

I've also been experimenting with RdfContext from Gregg Kellogg http://github.com/gkellogg/rdf_context

What library do you use and what are its pros and cons?

flag	asked Jan 27 at 12:34 billroberts 718●8

Gregg Kellogg · Accepted Answer · 2010-02-08 16:31:37Z UTC

I started RdfContext due to frustrations with the Redland Ruby Bindings. The primary issues for me were installation problems across different platforms, which is a real problem when you're developing a gem as a utility for non-programmers to use. A buggy Rdfa parser (which has since been updated and is now state-of-the-spec). And garbage collection issues, which didn't affect operation, but left complaints all over the place.

Redland's still the way to go for straight-out performance, but I felt that a pure-Ruby approach was necessary. The works not done; more stores could be added, and performance can be improved. I'm working on updating the N3 parser to take advantage of Quoted Graphs and be more compliant. I'd also like to add a SPARQL engine and work on better Rails integration.

Arto Bendiken · Answer 2 · 2010-04-25 23:17:39Z UTC

The active pure-Ruby projects at this moment are RDF.rb, RdfContext and RDFObjects, and the most convenient Redland binding for Ruby is Redleaf.

I'm the lead developer for RDF.rb, so that's what I use. In brief, RDF.rb's pros are:

100% pure Ruby with minimal dependencies and no bloat.
100% free and unencumbered public domain software.
Extremely well-commented source code.
Compatible with Ruby 1.8.x, Ruby 1.9.x, and JRuby.
Provides a clean RDF object model and related APIs.
Fully modularized with a lean core, most non-core functionality available as add-on plugin gems.
Supports parsing and serializing N-Triples, Turtle, RDF/XML, RDF/JSON, and TriX data.
Supports accessing and storing RDF data in SQLite, PostgreSQL, MongoDB, Cassandra, Sesame, RedStore, and the Talis Platform.

The cons are primarily the lack of a SPARQL engine at present (a SPARQL client already exists, however).

If you wish to learn more, there are several in-depth tutorials available for RDF.rb:

The public-rdf-ruby@w3.org mailing list has also undergone something of a revival in the last month, so I'd highly recommend that anyone who cares about RDF in Ruby subscribe to the list and participate in the ongoing discussions.

Ross Singer · Answer 3 · 2010-04-26 12:27:22Z UTC

ActiveRDF pretty much requires that you have a persistence layer with a SPARQL endpoint, which, in my case, at least, isn't always a given when I'm just trying to parse and work with some RDF. It's also very Rails-centric.

The major difference between RDFObjects (full disclosure, I am the main developer) and RDF.rb and RdfContext is that its intention is to abstract the graphs away into something more idiomatically Ruby-ish (aligning it more, API-wise, with ActiveRDF). The other two stick pretty closely to RDF for their interfaces. Like RdfContext, the only reason I started RDFObjects was a completely inability to get the Redland bindings working.

I'm not sure I can subscribe to any of them being "pure-Ruby", per se, since RDFObjects and RdfContext require Nokogiri and RDF.rb requires raptor to work with anything but ntriples or JSON (basically), but these are certainly much lower barriers than the Redland bindings have presented.

Anyway, it's nice to see an ecosystem building (finally) around RDF for Ruby.

davidseth · Answer 4 · 2010-07-05 12:00:18Z UTC

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Take a look at the excellent Spira Project. "It's time to breathe life into your linked data."

And a blog post with further info: http://blog.datagraph.org/2010/05/spira

answered Jul 5 at 12:00

davidseth
31●1

thanks - looks interesting – billroberts Jul 5 at 14:08

Harshal · Answer 5 · 2010-04-26 03:04:54Z UTC

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As an alternative, you can explore ActiveRDF. A fork is being developed by enthusiasts on GitHub. I had used it a couple of years ago. Hope that helps.

answered Apr 26 at 3:04

Harshal
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Ian · Answer 6 · 2010-04-27 10:15:49Z UTC

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@Arto Bendiken I think your RDF.rb project is pretty interesting, but surely it's not "100% pure Ruby" since you rely on Redland to parse RDF/XML and Turtle?

Ian

answered Apr 27 at 10:15

Ian
327●3

	RDF.rb itself is indeed 100% pure Ruby with no native dependencies. RDF::Raptor, which you refer to, is an external add-on plugin that happens to rely on Raptor. It is not to be considered part of RDF.rb itself, but rather part of the RDF.rb ecosystem. We draw a clear line between the core library and plugins, so that plugins (rubygems.org/search?query=rdf-) can have any dependencies they want. For instance, people working with JRuby may create JRuby-dependent plugins that rely on Jena or Sesame, but that's not going to affect nor interest any RDF.rb users not working with Java. – Arto Bendiken Apr 27 at 17:19
	think this answer should be a comment on the earlier answer – Ian Davis Jul 5 at 13:12
	A feature of the StackExchange software is that you can't comment on another answer until you have earned enough rep. When I posted this answer, it was because I wasn't allowed to comment. – Ian Jul 6 at 16:20

What Ruby library do you use for working with RDF?

6 Answers