Merge pull request #385 from bci-oss/373-fix-logical-shacl-components

Fix evaluation of logical SHACL components

Author: atextor

core/esmf-aspect-model-validator/src/main/java/org/eclipse/esmf/aspectmodel/shacl/ShaclValidator.java

@@ -41,6 +41,7 @@
 import org.apache.jena.rdf.model.Property;
 import org.apache.jena.rdf.model.RDFNode;
 import org.apache.jena.rdf.model.Resource;
+import org.apache.jena.rdf.model.ResourceFactory;
 import org.apache.jena.rdf.model.Statement;
 import org.apache.jena.vocabulary.RDF;
 
@@ -78,8 +79,7 @@ public ShaclValidator( final Model shapesModel ) {
     * If you have more than one element to validate, prefer the method {@link #validateElements(List)} to calling this method in a loop
     * for better performance.
     * {@link Resource#getModel()} on the element must not return null, i.e., the resource may not be created using
-    * {@link org.apache.jena.rdf.model.ResourceFactory#createProperty(String)}, but instead must be created via
-    * {@link Model#createResource(String)}.
+    * {@link ResourceFactory#createProperty(String)}, but instead must be created via {@link Model#createResource(String)}.
     *
     * @param element the element to be validated
     * @return the list of {@link Violation}s if there are violations
@@ -170,45 +170,59 @@ public List<Violation> validateElements( final List<Resource> elements ) {
    }
 
    public List<Violation> validateShapeForElement( final Resource element, final Shape.Node nodeShape, final Model resolvedModel ) {
+      return validateShapeForElement( element, nodeShape, resolvedModel, Optional.empty() );
+   }
+
+   public List<Violation> validateShapeForElement( final Resource element, final Shape.Node nodeShape, final Model resolvedModel,
+         final Optional<EvaluationContext> parentContext ) {
       final List<Violation> violations = new ArrayList<>();
       for ( final Shape.Property propertyShape : nodeShape.properties() ) {
-         for ( final Constraint constraint : propertyShape.attributes().constraints() ) {
-            final List<Statement> reachableNodes = propertyShape.path().accept( element, retriever );
-            // For all values that are present on the target node, check the applicable shapes and collect violations
-            for ( final Statement assertion : reachableNodes ) {
-               final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.of( propertyShape ),
-                     Optional.of( assertion.getPredicate() ), List.of( assertion ), this, resolvedModel );
-               violations.addAll( constraint.apply( assertion.getObject(), context ) );
-            }
-
-            // important detail: Sparql constraints must run independent of whether there are any matches via the sh:path property or not
-            // ( the check could be the verification whether the property exists )
-            if ( reachableNodes.isEmpty() && constraint instanceof SparqlConstraint ) {
-               final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.of( propertyShape ), Optional.empty(),
-                     List.of(), this, resolvedModel );
-               violations.addAll( constraint.apply( null, context ) );
-            }
-
-            // MinCount needs to be handled separately: If the property is not used at all on the target node, but a MinCount constraints
-            // >= 1 exists, a violation must be emitted even though no value for the property exists
-            if ( reachableNodes.isEmpty() && constraint instanceof MinCountConstraint
-                  && propertyShape.path() instanceof final PredicatePath predicatePath ) {
-               final Property rdfProperty = resolvedModel.createProperty( predicatePath.predicate().getURI() );
-               final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.of( propertyShape ),
-                     Optional.of( rdfProperty ), List.of(), this, resolvedModel );
-               violations.addAll( constraint.apply( null, context ) );
-            }
-         }
+         violations.addAll( validateShapeForElement( element, nodeShape, propertyShape, resolvedModel, parentContext ) );
       }
 
-      final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.empty(), Optional.empty(), List.of(), this,
-            resolvedModel );
+      final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.empty(), Optional.empty(),
+            parentContext, List.of(), this, resolvedModel );
       for ( final Constraint constraint : nodeShape.attributes().constraints() ) {
          if ( !constraint.canBeUsedOnNodeShapes() ) {
             continue;
          }
          violations.addAll( constraint.apply( element, context ) );
       }
+      return violations;
+   }
+
+   public List<Violation> validateShapeForElement( final Resource element, final Shape.Node nodeShape, final Shape.Property propertyShape,
+         final Model resolvedModel, final Optional<EvaluationContext> parentContext ) {
+      final List<Violation> violations = new ArrayList<>();
+
+      for ( final Constraint constraint : propertyShape.attributes().constraints() ) {
+         final List<Statement> reachableNodes = propertyShape.path().accept( element, retriever );
+         // For all values that are present on the target node, check the applicable shapes and collect violations
+         for ( final Statement assertion : reachableNodes ) {
+            final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.of( propertyShape ),
+                  Optional.of( assertion.getPredicate() ), parentContext, List.of( assertion ), this, resolvedModel );
+            violations.addAll( constraint.apply( assertion.getObject(), context ) );
+         }
+
+         // important detail: Sparql constraints must run independent of whether there are any matches via the sh:path property or not
+         // ( the check could be the verification whether the property exists )
+         if ( reachableNodes.isEmpty() && constraint instanceof SparqlConstraint ) {
+            final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.of( propertyShape ), Optional.empty(),
+                  parentContext, List.of(), this, resolvedModel );
+            violations.addAll( constraint.apply( null, context ) );
+         }
+
+         // MinCount needs to be handled separately: If the property is not used at all on the target node, but a MinCount constraints
+         // >= 1 exists, a violation must be emitted even though no value for the property exists
+         if ( reachableNodes.isEmpty() && constraint instanceof MinCountConstraint ) {
+            final Optional<Property> property = propertyShape.path() instanceof PredicatePath ?
+                  Optional.of( resolvedModel.createProperty( ((PredicatePath) propertyShape.path()).predicate().getURI() ) ) :
+                  Optional.empty();
+            final EvaluationContext context = new EvaluationContext( element, nodeShape, Optional.of( propertyShape ),
+                  property, parentContext, List.of(), this, resolvedModel );
+            violations.addAll( constraint.apply( null, context ) );
+         }
+      }
 
       return violations;
    }
@@ -267,4 +281,8 @@ public List<Shape.Node> getShapes() {
    public Model getShapesModel() {
       return shapesModel;
    }
+
+   public PathNodeRetriever getRetriever() {
+      return retriever;
+   }
 }

core/esmf-aspect-model-validator/src/main/java/org/eclipse/esmf/aspectmodel/shacl/Shape.java

@@ -16,24 +16,37 @@
 import java.util.List;
 import java.util.Optional;
 
+import org.eclipse.esmf.aspectmodel.shacl.constraint.Constraint;
+import org.eclipse.esmf.aspectmodel.shacl.path.Path;
+
 import org.apache.jena.query.Query;
 import org.apache.jena.rdf.model.RDFNode;
 import org.apache.jena.rdf.model.Resource;
 
-import org.eclipse.esmf.aspectmodel.shacl.path.Path;
-import org.eclipse.esmf.aspectmodel.shacl.constraint.Constraint;
-
 /**
  * Implements <a href="https://www.w3.org/TR/shacl/#node-shapes">sh:NodeShape</a>
  */
 public interface Shape {
    Attributes attributes();
 
+   <T> T accept( Visitor<T> visitor );
+
    /**
     * Implements the valid values for <a href="https://www.w3.org/TR/shacl/#NodeKindConstraintComponent">sh:nodeKind</a>
     */
    enum NodeKind {
-      BlankNode, IRI, Literal, BlankNodeOrIRI, BlankNodeOrLiteral, IRIOrLiteral;
+      BlankNode( "an anonymous node" ),
+      IRI( "a named element" ),
+      Literal( "a value" ),
+      BlankNodeOrIRI( "an anonymous node or a named element" ),
+      BlankNodeOrLiteral( "an anonymous node or a value" ),
+      IRIOrLiteral( "a named element or a value" );
+
+      private final String humanRepresentation;
+
+      NodeKind( final String humanRepresentation ) {
+         this.humanRepresentation = humanRepresentation;
+      }
 
       public static NodeKind forNode( final RDFNode node ) {
          if ( node.isLiteral() ) {
@@ -47,6 +60,10 @@ public static NodeKind forNode( final RDFNode node ) {
          }
          throw new RuntimeException( "Invalid nodekind: " + node );
       }
+
+      public String humanReadable() {
+         return humanRepresentation;
+      }
    }
 
    record Attributes(
@@ -76,6 +93,10 @@ record Node(
          Attributes attributes,
          List<Property> properties
    ) implements Shape {
+      @Override
+      public <T> T accept( final Visitor<T> visitor ) {
+         return visitor.visitNodeShape( this );
+      }
    }
 
    /**
@@ -85,6 +106,16 @@ record Property(
          Attributes attributes,
          Path path
    ) implements Shape {
+      @Override
+      public <T> T accept( final Visitor<T> visitor ) {
+         return visitor.visitPropertyShape( this );
+      }
+   }
+
+   interface Visitor<T> {
+      T visitNodeShape( Shape.Node shapeNode );
+
+      T visitPropertyShape( Shape.Property propertyShape );
    }
 }