oxigraph/README.md

Oxigraph

Oxigraph is a work in progress graph database implementing the SPARQL standard.

There is no released version yet.

Its goal is to provide a compliant, safe and fast graph database based on the RocksDB key-value store. It is written in Rust.

It is split into multiple parts:

• The lib directory contains the database written as a Rust library
• The server directory contains a stand-alone binary of a web server implementing the SPARQL 1.1 Protocol.
• The wikibase directory contains a stand-alone binary of a web server able to synchronize with a Wikibase instance.

Are currently implemented:

• SPARQL 1.1 Query except FROM and FROM NAMED.
• Turtle, TriG, N-Triples, N-Quads and RDF XML RDF serialization formats for both data ingestion and retrieval using the Rio library.
• SPARQL Query Results XML Format and SPARQL Query Results JSON Format.

A preliminary benchmark is provided.

Run the web server

Build

You need to have a recent stable version of Rust and Cargo installed. You also need llvm (and clang) to build the rocksDB and other bindings.

If it's done, executing cargo build --release in the root directory of this repository should compile the full server after having downloaded its dependencies. It will create a fat binary in target/release/oxigraph_server.

Usage

Run ./oxigraph_server to start the server. It listen by default on localhost:7878.

The server provides an HTML UI with a form to execute SPARQL requests.

It provides the following routes:

• / allows to POST data to the server. For example curl -f -X POST -H 'Content-Type:application/n-triples' --data-binary "@MY_FILE.nt" http://localhost:7878/ will add the N-Triples file MY_FILE.nt to the server repository. Turtle, TriG, N-Triples, N-Quads and RDF XML are supported.
• /query allows to evaluate SPARQL queries against the server repository following the SPARQL 1.1 Protocol. For example curl -f -X POST -H 'Content-Type:application/sparql-query' --data 'SELECT * WHERE { ?s ?p ?o } LIMIT 10' http://localhost:7878/query. This route supports content negotiation and could return Turtle, N-Triples, RDF XML, SPARQL Query Results XML Format and SPARQL Query Results JSON Format.

Use oxigraph_server --help to see the possible options when starting the server.

Run the web server for Wikibase

Build

You need to have a recent stable version of Rust and Cargo installed.

If it's done, executing cargo build --release in the root directory of this repository should compile the full server after having downloaded its dependencies. It will create a fat binary in target/release/oxigraph_wikibase.

Usage

To start a server that is synchronized with test.wikidata.org you should run:

./oxigraph_wikibase --mediawiki_api=https://test.wikidata.org/w/api.php --mediawiki_base_url=https://test.wikidata.org/wiki/ --namespaces=0,120 --file=test.wikidata

It creates a SPARQL endpoint listening to localhost:7878/query that could be queried just like Blazegraph.

The configuration parameters are:

• mediawiki_api URL of the MediaWiki API to use
• mediawiki_base_url Base URL of MediaWiki pages like https://test.wikidata.org/wiki/ for test.wikidata.org or http://localhost/w/index.php?title= for "vanilla" installations.
• namespaces The ids of the Wikibase namespaces to synchronize with, separated by ,.
• file Path of where Oxigraph should store its data.

License

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Futures by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.