Validate rdf:JSON typed literal

json-literals.ttl

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix ex: <http://example.com/> .

# valid JSON literals
ex:bob ex:has '{"name": robert"}'^^rdf:JSON .
ex:bob ex:has '{"name": ["robert", "bob"]}'^^rdf:JSON .

# invalid JSON literals
ex:bob ex:has '{"name": "robert"}'^^rdf:JSON .
ex:bob ex:has '{"name": ["robert", "bob",]}'^^rdf:JSON .

jsontest.rq

PREFIX js: <http://jena.apache.org/ARQ/jsFunction#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

SELECT ?o (js:isJsonLiteralValid(?o) AS ?isValid)
WHERE {
  ?s ?p ?o .
  FILTER (datatype(?o) = rdf:JSON)
}

myjs.js

// validate json
function isJsonLiteralValid(jsonLiteral) {
  try {
    JSON.parse(jsonLiteral);
    return true;
  } catch(e) {
    return false;
  }
}

script.sh

#!/bin/bash

export JVM_ARGS=-Djena:scripting=true
arq --set arq:js-library=myjs.js --query jsontest.rq --data json-literals.ttl