InfoBus SPARQL

SPARQL endpoint for transit data using Apache Jena Fuseki and GTFS ontologies.

Overview

This project provides a SPARQL endpoint for querying transit data based on the General Transit Feed Specification (GTFS). It uses Apache Jena Fuseki as the triplestore and includes a comprehensive set of GTFS ontologies.

Features

• Apache Jena Fuseki Server: High-performance RDF triplestore with SPARQL endpoint
• GTFS Ontologies: Comprehensive ontologies covering all GTFS data elements:
  • gtfs.ttl - Core GTFS ontology with base classes and properties
  • stops.ttl - Ontology for stop locations, stations, and facilities
  • trips.ttl - Ontology for trip scheduling and operations
  • routes.ttl - Ontology for transit routes
  • calendar.ttl - Ontology for service schedules and calendars
  • agency.ttl - Ontology for transit agencies
  • shapes.ttl - Ontology for route shapes and geographic paths
  • fares.ttl - Ontology for fare information and pricing rules
• TDB2 Storage: Efficient persistent storage using Apache Jena TDB2
• Auto-loading: Automatically loads ontologies from the ontology/ directory on startup

Project Structure

infobus-sparql/
├── ontology/           # GTFS ontology files (.ttl)
│   ├── gtfs.ttl
│   ├── stops.ttl
│   ├── trips.ttl
│   ├── routes.ttl
│   ├── calendar.ttl
│   ├── agency.ttl
│   ├── shapes.ttl
│   └── fares.ttl
├── data/
│   └── tdb2/          # TDB2 triplestore data (auto-created)
├── config/
│   └── fuseki-config.ttl  # Fuseki server configuration
├── src/
│   └── main/java/
│       └── com/simovilab/infobus/
│           └── FusekiServer.java
└── pom.xml            # Maven project configuration

Requirements

• Java 11 or higher
• Maven 3.6 or higher

Getting Started

1. Build the Project

mvn clean package

This will compile the code and create an executable JAR file in the target/ directory.

2. Run the Server

java -jar target/infobus-sparql-1.0.0-SNAPSHOT.jar

Or run directly with Maven:

mvn exec:java -Dexec.mainClass="com.simovilab.infobus.FusekiServer"

3. Access the Endpoints

Once the server is running, the following endpoints are available:

• SPARQL Query: http://localhost:3030/infobus/sparql
• SPARQL Update: http://localhost:3030/infobus/update
• Graph Store: http://localhost:3030/infobus/data
• Fuseki UI: http://localhost:3030/ (if using full Fuseki server)

Using the SPARQL Endpoint

Example Query

Query all GTFS classes defined in the ontologies:

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX gtfs: <http://vocab.gtfs.org/terms#>

SELECT ?class ?label ?comment
WHERE {
  ?class rdf:type owl:Class .
  ?class rdfs:label ?label .
  OPTIONAL { ?class rdfs:comment ?comment }
  FILTER(STRSTARTS(STR(?class), "http://vocab.gtfs.org/terms#"))
}
ORDER BY ?label

Inserting Data

You can insert transit data using SPARQL UPDATE:

PREFIX gtfs: <http://vocab.gtfs.org/terms#>
PREFIX ex: <http://example.org/transit/>

INSERT DATA {
  ex:agency1 a gtfs:Agency ;
    gtfs:agencyId "METRO" ;
    gtfs:agencyName "Metro Transit" ;
    gtfs:agencyUrl <http://metro.example.org> ;
    gtfs:agencyTimezone "America/New_York" .
}

Ontology Documentation

Core GTFS Ontology (gtfs.ttl)

Defines the base classes and properties for GTFS data:

• Classes: Agency, Stop, Route, Trip, StopTime, Calendar, etc.
• Properties: Identifiers, names, relationships
• Route types: Bus, Subway, Rail, Ferry, etc.

Stops Ontology (stops.ttl)

Extended ontology for stop locations:

• Stop location types (platform, station, entrance, etc.)
• Geographical properties
• Accessibility features
• Amenities (shelters, benches, ticket machines, etc.)

Trips Ontology (trips.ttl)

Extended ontology for trip operations:

• Trip properties (headsign, direction, block ID)
• Stop time properties (pickup/dropoff types)
• Trip status (scheduled, delayed, canceled)
• Accessibility information

Routes Ontology (routes.ttl)

Extended ontology for transit routes:

• Route properties (colors, URLs, descriptions)
• Route classifications (local, express, rapid transit)
• Route patterns

Calendar Ontology (calendar.ttl)

Extended ontology for service schedules:

• Service availability by day of week
• Date ranges for service
• Calendar exceptions (holidays, special events)
• Frequency-based service

Agency Ontology (agency.ttl)

Extended ontology for transit agencies:

• Agency contact information
• Service areas
• Agency relationships (parent/subsidiary)

Shapes Ontology (shapes.ttl)

Extended ontology for route shapes:

• Shape points and sequences
• Geographic coordinates
• Distance calculations
• GeoJSON and WKT representations

Fares Ontology (fares.ttl)

Extended ontology for fare information:

• Fare attributes and pricing
• Payment methods
• Fare rules and zones
• Discount types and fare products

Development

Adding More Ontologies

1. Create a new .ttl file in the ontology/ directory
2. Define your RDF classes and properties using Turtle syntax
3. Restart the server - ontologies are auto-loaded

Custom Configuration

Edit config/fuseki-config.ttl to customize:

• Dataset location
• Service endpoints
• Security settings
• Query timeouts

License

Apache License 2.0 - See LICENSE file for details

Contributing

Contributions are welcome! Please submit pull requests or open issues for bugs and feature requests.

Resources

• GTFS Reference
• Apache Jena Documentation
• SPARQL 1.1 Query Language
• RDF 1.1 Turtle