SHACL-JS Functions Not Executing Correctly in pyshacl

[Myasir92]

JavaScript constraint functions defined in external .js files are not executing the actual code in the file. The validation behaves as if a different version of the function is being used, suggesting a caching issue or file loading problem.

Environment

• pyshacl version: 0.30.1
• pyduktape2 version: 0.5.0
• Python version: 3.10.12
• OS: WSL Ubuntu on Windows
• rdflib version: 7.4.0

Expected Behavior

When a SHACL-JS constraint references an external JavaScript file, the current content of that file should be loaded and executed during validation.

Actual Behavior

The validation executes a different version of the JavaScript function than what is currently in the file, suggesting either:

1. The JavaScript file is cached and not reloaded
2. The wrong file is being loaded

Minimal Reproduction Case

1. Setup Files

data.ttl:

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

ex:Item1 a ex:Product ;
    ex:name "Test Name" .

shape.ttl:

@prefix sh: <http://www.w3.org/ns/shacl#> .
@prefix ex: <http://example.org/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

ex:ProductNameShape
    a sh:NodeShape ;
    sh:targetClass ex:Product ;
    sh:property [
        sh:path ex:name ;
        sh:js [
            a sh:JSConstraint ;
            sh:message "Name must be between 3 and 100 characters" ;
            sh:jsFunctionName "validateName" ;
            sh:jsLibrary [
                sh:jsLibraryURL "validate.js"^^xsd:anyURI ;
            ] ;
        ] ;
    ] .

validate.js:

function validateName($value) {
    var name = $value;
    var length = name.length;
    // Return true if length is between 3 and 100
    return length >= 3 && length <= 100;
}

2. Run Validation

from pyshacl import validate

r = validate(
    'data.ttl',
    shacl_graph='shape.ttl',
    js=True,
    advanced=True
)

conforms, results_graph, results_text = r
print(f"Conforms: {conforms}")
print(results_text)

3. Observe the Problem

Test Case: "Test Name" = 9 characters

Expected Result:

• Since 9 is between 3 and 100, the function should return true
• Validation should PASS (conforms = True)

Actual Result:

Conforms: False
Results (1):
Constraint Violation in JSConstraint
    Focus Node: ex:Item1
    Value Node: Literal("Test Name")
    Message: Name must be between 3 and 100 characters

The validation FAILS, meaning the JavaScript function returned false, but according to the code return length >= 3 && length <= 100, it should return true for 9 characters.

Additional Evidence

Test with Multiple Items

data.ttl with 3 items:

@prefix ex: <http://example.org/> .

ex:Item1 a ex:Product ;
    ex:name "Hello World" .          # 11 characters

ex:Item2 a ex:Product ;
    ex:name "X" .                     # 1 character

ex:Item3 a ex:Product ;
    ex:name "Sample Product" .        # 14 characters

Current JavaScript function:

function validateName($value) {
    var name = $value;
    var length = name.length;
    return length >= 3 && length <= 100;  // Accept 3-100 chars
}

Expected Results:

• "X" (1 char) → FAIL (< 3)
• "Hello World" (11 chars) → PASS (3 ≤ 11 ≤ 100)
• "Sample Product" (14 chars) → PASS (3 ≤ 14 ≤ 100)
• Total: 1 failure

Actual Results:

Validation FAILED
Total errors: 3

All 3 items fail validation

This confirms the JavaScript is not executing the current code. It appears to be executing an older version where the condition was different (possibly >= 90 && <= 100).

Impact

This makes SHACL-JS unreliable for production use because:

• Changes to JavaScript validation logic don't take effect
• No way to debug or verify which version of the code is executing
• Unpredictable validation behavior
• Cannot trust that the JavaScript function in the file is what's being executed

References:

• SHACL-JS Spec: https://www.w3.org/TR/shacl-js/
• pyshacl Repository: https://github.com/RDFLib/pySHACL
• Duktape: https://duktape.org/

[ashleysommer]

Thanks for the bug report @Myasir92 ! I appreciate it. SHACL-JS support in PySHACL is the least used feature, and gets the least amount of real world testing. Its not surprising you've found an issue like this. This could be a duktape bug, but more likely an issue with how it is implemented in PySHACL. We will look into it, but I can't give you a timeframe for when it would be fixed.