GraFa

Faceted Browsing over Wikidata triples

Use the system

The system is currently running on: http://grafa.dcc.uchile.cl

Installation

Required libraries:

• Lucene 6.5
• Tomcat 7
• RDF4J 2.2

Config file

The file facet.properties contains the following options:

• languages: list of supported languages (using the same language tag from the dataset)
• entityIRI: prefix for entities
• propertyIRI: prefix for properties
• labelIRI: predicate of the triple containing the label
• descriptionIRI: predicate of the triple containing the description
• alt_labelIRI: predicate of the triples containing alt labels or aliases
• instanceOf: IRI (with no prefix) of the type or instance of predicate
• image: IRI (with no prefix) of the image predicate
• entityPrefix: prefix of all entities (excluding the domain prefix)

Binaries

The included build.xml generates several jar files. These are the most important:

• index.jar: Creates an index from all entities based on an NT file
• rank.jar: Computes the graph and the Page Rank value of each entity
• boosts.jar: Copies the index from index.jar but adding the ranks from rank.jar
• cache.jar: Generates a list of all queries with a large results set that need caching.
• instances.jar: Creates an index of all instances/types of the main index and also caches the results from the list of cache.jar
• values.jar: Creates the cache for values for every property of every query that needs caching. This process may take a couple of days.
• grafa.war: Tomcat Webapp's war file. The config file need the directory of the indexes.
• The other jar files are for debugging and generate statistics (there may also be unused classes)