To get JSON results from a SPARQL query you can make a HTTP request to https://query.wikidata.org/sparql?query={SPARQL}&format=json, which with wikidata-sdk
can be done like this:
import { WBK } from 'wikibase-sdk'
// Make sure you initialize wbk with a sparqlEndpoint
const wbk = WBK({
instance: 'https://my-wikibase-instan.se',
sparqlEndpoint: 'https://query.my-wikibase-instan.se/sparql'
})
const sparql = 'SELECT * WHERE { ?s ?p ?o } LIMIT 10'
const url = wbk.sparqlQuery(sparql)
const headers = { 'User-Agent': '<FILL IN YOUR USER-AGENT INFORMATION>' }; // see https://foundation.wikimedia.org/wiki/Policy:User-Agent_policy
// request the generated URL with your favorite HTTP request library
request({ method: 'GET', url, headers})
For more information on including the correct User-Agent
You can then simplify the response using wbk.simplify.sparqlResults
.
Exemple taken from inventaire SPARQL queries (here written using ES6 template string capabilities)
const authorQid = 'Q535'
const sparql = `
SELECT ?work ?date WHERE {
?work wdt:P50 wd:${authorQid} .
OPTIONAL {
?work wdt:P577 ?date .
}
}
`
const url = wbk.sparqlQuery(sparql)
// => https://query.my-wikibase-instan.se/sparql?format=json&query=%0APREFIX%20wd%3A%20%3Chttp%3A%2F%2Fwww.wikidata.org%2Fentity%2F%3E%0APREFIX%20wdt%3A%20%3Chttp%3A%2F%2Fwww.wikidata.org%2Fprop%2Fdirect%2F%3E%0A%0ASELECT%20%3Fwork%20%3Fdate%20WHERE%20%7B%0A%20%20%3Fwork%20wdt%3AP50%20wd%3AQ535%20.%0A%20%20OPTIONAL%20%7B%0A%20%20%20%20%3Fwork%20wdt%3AP577%20%3Fdate%20.%0A%20%20%7D%0A%7D%0A
Querying this url should return a big collection of objects with work
and date
attributes corresponding to all Mr Q535's works, that you might want to simplify before working with it.
If the generated request URL gets too long, you can make a POST request instead
const [ url, body ] = wbk.sparqlQuery(sparql).split('?')
request({ method: 'POST', url, body })