banana-rdf

An RDF library in Scala

banana-rdf is a library for RDF, SPARQL and Linked Data technologies in Scala.

It can be used with existing libraries without any added cost. There is no wrapping involved: you manipulate directly the real objects. We currently support Jena, Sesame and Plantain, a pure Scala implementation.

Features

banana-rdf emphasizes type-safety and immutability, so it can come with some cost when the underlying implementation is very mutable (I'm looking at you, Jena and Sesame). We try to keep a clear distinction between the core concepts and the enhanced syntax that Scala can give us.

RDF itself is defined as a record of types. Implementations just have to plug their own types. And because types alone are not enough, we introduce the RDFOps typeclass, which defines the mandatory operations that an RDF implementation must implement. SparqlOps does the same for SPARQL.

With banana-rdf, you get Diesel, a nice DSL to build and navigate within pointed graphs (graphs with a pointer to an inner node). You also get an abstraction for graph stores (GraphStore), which do not have to be SPARQL engines (SparqlEngine). Of course, you can serialize and deserialize most of the RDF syntaxes as well as JSON-LD (RDFa will come soon).

banana-rdf introduces the concept of binders, which let you bridge the Scala and RDF worlds. Most of the common datastructures are already available, and you can even map your own classes. Unlike usual ORM techniques, this does not rely on annotation or reflection.

Until we write thorough documentation, the best place to understand what you can do is to go through the test suite.

How to start geeking

You only need a recent version of Java, that's all:

$ git clone git@github.com:w3c/banana-rdf.git
$ cd banana-rdf
$ sbt

It's also easy to just build specific target platforms:

$ sbt +banana_js/test    # for javascript only 
$ sbt +banana_jvm/test   # for jvm only

( note: scala-js compilation uses more memory. see travis.yml )

IDE Setup

banana-rdf works with both eclipse and IntelliJ IDEA.

global.sbt

Independent of your preferred IDE, optionally the add the following line to ~/.sbt/0.13/global.sbt to prevent the generation of empty source directories:

    unmanagedSourceDirectories in Compile ~= { _.filter(_.exists) }

Eclipse

Eclipse should work "out of the box" with the addition of the following global settings:

In ~/.sbt/0.13/global.sbt:

    unmanagedSourceDirectories in Compile ~= { _.filter(_.exists) }

In ~/.sbt/0.13/plugins/build.sbt

    addSbtPlugin("com.typesafe.sbteclipse" % "sbteclipse-plugin" % "2.5.0")

To generate eclipse project files, just run the command:

$ sbt eclipse

IntelliJ IDEA

IntelliJ IDEA works with just one global change:

In ~/.sbt/0.13/plugins/build.sbt

    addSbtPlugin("com.github.mpeltonen" % "sbt-idea" % "1.6.0")

To generate IntelliJ project files, just run the command:

$ sbt gen-idea

Community

For discussions that don't fit in the issues tracker, you may try either

• the w3c banana-rdf mailing list, for longer discussions
• the banana-rdf irc channel on freenode using a dedicated IRC client connecting to irc://irc.freenode.net:6667/banana-rdf or using the freenode html interface, for quick real time socialising

Contributions

All contributions are welcome. By contributing, you accept to give the ownership of your contribution to the World Wide Web Consortium. They are a nonprofit organization and just want to simplify the governance of this opensource project.

Before contributing please make sure to copy the bin/pre-commit shell script to the .git/hooks/ directory of your clone. This will ensure that all your commits are formatted in a consistent way before you push, making it easier to see the real diffs in a project. On Unix you can do this with the command

$ cp bin/pre-commit .git/hooks/

Code of Conduct

Banana-RDF contributors all agree to follow the W3C Code of Ethics and Professional Conduct.

If you want to take action, feel free to contact Alexandre Bertails alexandre@bertails.org. You can also contact W3C Staff as explained in W3C Procedures.

Licence

This source code is made available under the W3C Licence. This is a business friendly license.