Comunica SPARQL AMF Init Actor

Comunica SPARQL AMF is a SPARQL query engine for JavaScript that takes into account approximate membership functions.

This can be tested using the feature-handlers-amf-2 branch in the LDF Server.

This module is part of the Comunica framework.

Install

$ yarn add @comunica/actor-init-sparql-amf

or

$ npm install -g @comunica/actor-init-sparql-amf

Usage

Show 100 triples from http://localhost:3000/dataset:

$ comunica-sparql-amf http://localhost:3000/dataset "CONSTRUCT WHERE { ?s ?p ?o } LIMIT 100"

Show the help with all options:

$ comunica-sparql-amf --help

Just like Comunica SPARQL, a dynamic variant (comunica-dynamic-sparql-amf) also exists.

Read more about querying from the command line.

Usage within application

This engine can be used in JavaScript/TypeScript applications as follows:

const newEngine = require('@comunica/actor-init-sparql-amf').newEngine;
const myEngine = newEngine();

const result = await myEngine.query(`
  SELECT * WHERE {
      ?s ?p ?o
  }`, {
  sources: ['http://localhost:3000/dataset'],
});

// Consume results as a stream (best performance)
result.bindingsStream.on('data', (binding) => {
    console.log(binding.get('?s').value);
    console.log(binding.get('?s').termType);

    console.log(binding.get('?p').value);

    console.log(binding.get('?o').value);
});

// Consume results as an array (easier)
const bindings = await result.bindings();
console.log(bindings[0].get('?s').value);
console.log(bindings[0].get('?s').termType);

Read more about querying an application.

Usage as a SPARQL endpoint

Start a webservice exposing http://localhost:3000/dataset via the SPARQL protocol, i.e., a SPARQL endpoint.

$ comunica-sparql-amf-http https://www.rubensworks.net/

Show the help with all options:

$ comunica-sparql-amf-http --help

The SPARQL endpoint can only be started dynamically. An alternative config file can be passed via the COMUNICA_CONFIG environment variable.

Use bin/http.js when running in the Comunica monorepo development environment.

Read more about setting up a SPARQL endpoint.