README
Comunica SPARQL Solid
Comunica SPARQL Solid is a SPARQL query engine for JavaScript that can query over Solid data pods.
This package is safe to use in both Node.js and browser environments.
This module is part of the Comunica framework. Click here to learn more about Comunica and Solid.
Known issues
This library has the following known issues in certain cases, that are out of our control (but have been reported).
- Web Workers: This library can not be used within due to an open issue in https://github.com/inrupt/solid-client-authn-js/issues/1657
- Enterprise Solid Server (https://pod.inrupt.com/):
- Patch requests are not accepted, so only new documents can be created, but existing ones can not be modified.
- Due to missing
Accept-Patch
, andAccept-Put
headers, the destination type has to be forced. This will only work for creating new documents via theputLdp
destination type. Updating existing documents viapatchSparqlUpdate
are currently not possible because of the previous issue.
- Node Solid Server (https://solidcommunity.net/):
- Querying or updating existing documents fails with the error
Error translating between RDF formats
(https://github.com/solid/node-solid-server/issues/1618). Creating new documents does work.
- Querying or updating existing documents fails with the error
No issues are known with the Community Solid Server
Install
$ yarn add @comunica/query-sparql-solid
or
$ npm install -g @comunica/query-sparql-solid
Usage
Show 100 triples from a private resource by authenticating through the https://solidcommunity.net/ identity provider (when using https://pod.inrupt.com/, your IDP will be https://broker.pod.inrupt.com/):
$ comunica-sparql-solid --idp https://solidcommunity.net/ \
http://example.org/private-resource.ttl \
"SELECT * WHERE {
?s ?p ?o
} LIMIT 100"
This command will connect with the given identity provider, and open your browser to log in with your WebID. After logging in, the query engine will be able to access all the documents you have access to.
Show the help with all options:
$ comunica-sparql-solid --help
Just like Comunica SPARQL,
a dynamic variant (comunica-dynamic-sparql-solid
) 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/query-sparql-solid').newEngine;
const { interactiveLogin } = require('solid-node-interactive-auth');
// This will open your Web browser to log in
const session = await interactiveLogin({ oidcIssuer: 'https://solidcommunity.net/' });
const myEngine = newEngine();
const result = await myEngine.query(`
SELECT * WHERE {
?s ?p ?o
} LIMIT 100`, {
sources: [session.info.webId], // Sets your profile as query source
'@comunica/actor-http-inrupt-solid-client-authn:session': session,
});
// 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 a private resource via the SPARQL protocol, i.e., a SPARQL endpoint, by authenticating through the https://solidcommunity.net/ identity provider.
$ comunica-sparql-solid-http --idp https://solidcommunity.net/ \
http://example.org/private-resource.ttl
Show the help with all options:
$ comunica-sparql-solid-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.