LDCache

A cache for Linked Data-driven Web applications

Developers Workshop at ISWC 2014

2014-10-19

Hannes Ebner, PhDhannes@metasolutions.se

metasolutions.se

Overview

● Background

● Problem

● Solution

● Usage

Background (1/3)

Background (2/3)

Background (3/3)

Nobel Laureate

Problem

Nobel Prize

YAGO

Freebase

DBpedia

VIAF

Bio2RDF

Linked Life Data

...

...

Solution (1/2)

Solution (2/2)

● A Linked Data Cache: LDCache

● LDCache solves several problems

○ Reliability issues of third party data sources

○ Streamlining multiple dereferenciation steps

○ RDF format alignment

○ Offloading to a CDN

Usage (1/2)

● Java

○ Web container or standalone

● Simple JSON-based configuration

○ Root-resource(s) to start from

○ Predicates to follow

○ The maximum depth for graph traversal

○ Whitelist of destination prefixes

○ Whitelist of literal languages

○ ...

● Only pre-fetched resources are returned

● LDCache is not a caching proxy

Usage (2/2)

GET http://{ldc-base}/?

url=http://data.nobelprize.org/resource/laureate/6&follow=dbp:doctoralStudent,owl:sameAs,dbp:spouse&followDepth=3&includeDestinations=http://dbpedia.org/&format=application/ld+json

LDCache

License Apache License 2.0

Documentation http://entrystore.org/ldcache/

Source code https://bitbucket.org/metasolutions/ldcache/

Slides http://ebner.se/20141019

Paper http://ceur-ws.org/Vol-1268/paper12.pdf

Contact hannes@metasolutions.se