Closed shapes lead to a TypeError

[NSeydoux]

When trying to validate a closed shape (i.e. with sh:closed true), the following error is thrown:

(node:6649) UnhandledPromiseRejectionWarning: TypeError: Cannot read property 'equals' of undefined
    at RDFLibGraph.rdfListToArray (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/src/rdflib-graph.js:74:22)
    at validateClosed (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/src/validators.js:35:36)
    at ValidationFunction.execute (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/src/validation-function.js:11:22)
    at ValidationEngine.validateNodeAgainstConstraint (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/src/validation-engine.js:213:42)
    at ValidationEngine.validateNodeAgainstShape (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/src/validation-engine.js:171:16)
    at ValidationEngine.validateAll (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/src/validation-engine.js:144:20)
    at SHACLValidator.validate (/home/nseydoux/dev/sandbox/shapes-hal/node_modules/rdf-validate-shacl/index.js:35:27)
    at main (/home/nseydoux/dev/sandbox/shapes-hal/index.js:51:36)
    at Object.<anonymous> (/home/nseydoux/dev/sandbox/shapes-hal/index.js:68:1)
    at Module._compile (internal/modules/cjs/loader.js:1147:30)

To reproduce

Run the following code snippet:

const SHACLValidator = require("rdf-validate-shacl")
const {Parser} = require("n3")

const ttlData = `
@prefix ex: <http://example.org#>.
@prefix xsd: <http://www.w3.org/2001/XMLSchema#>.

ex:Alice
a ex:Person ;
ex:ssn "987-65-432A" .

ex:Bob
a ex:Person ;
ex:ssn "123-45-6789" ;
ex:ssn "124-35-6789" .

ex:Calvin
a ex:Person ;
ex:birthDate "1971-07-07"^^xsd:date ;
ex:worksFor ex:UntypedCompany .`

const ttlShape = `
@prefix ex: <http://example.org#>.
@prefix xsd: <http://www.w3.org/2001/XMLSchema#>.
@prefix sh: <http://www.w3.org/ns/shacl#>.
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.

ex:PersonShape
a sh:NodeShape ;
sh:targetClass ex:Person ;    # Applies to all persons
sh:property [                 # _:b1
    sh:path ex:ssn ;           # constrains the values of ex:ssn
    sh:maxCount 1 ;
    sh:datatype xsd:string ;
] ;
sh:property [                 # _:b2
    sh:path ex:worksFor ;
    sh:class ex:Company ;
    sh:nodeKind sh:IRI ;
] ;
#sh:closed true ;
sh:ignoredProperties ( rdf:type ) .`

async function main() {
    const parser = new Parser();
    const data = parser.parse(ttlData);
    const shapes = parser.parse(ttlShape);

    const validator = new SHACLValidator(shapes)
    console.log("coucou1")
    const report = await validator.validate(data)
     console.log("coucou2")
    // Check conformance: `true` or `false`
    console.log(report.conforms)

    for (const result of report.results) {
      // See https://www.w3.org/TR/shacl/#results-validation-result for details
      // about each method
      console.log(result.message)
      console.log(result.path)
      console.log(result.focusNode)
      console.log(result.severity)
      console.log(result.sourceConstraintComponent)
      console.log(result.sourceShape)
    }
} 

main()

The rdf-validate-shacl version is 0.1.1.

[martinmaillard]

This error is caused by a conflict between blank node IDs. The proper way to solve this would be to use the same data factory throughout the whole process:

const { DataFactory } = require('n3');

const parser = new Parser({ factory: DataFactory }); // <- factory option
const data = parser.parse(ttlData);
const shapes = parser.parse(ttlShape);

const validator = new SHACLValidator(shapes, { factory: DataFactory }) // <- factory option
const report = await validator.validate(data)

But because of an issue in N3.js, it won't solve your problem just yet. I'm working on it ⏳

[NSeydoux]

Thanks ! Does this mean that the issue would disappear altogether if the shape did not include blank nodes at all ?

[martinmaillard]

It should, yes :)

[martinmaillard]

Upgrading N3.js to 1.3.6 should fix your issue :)