Implemented SHACL Xone constraint

RDFSharp/Model/Validation/Abstractions/Constraints/RDFXoneConstraint.cs

@@ -0,0 +1,115 @@
+/*
+   Copyright 2012-2020 Marco De Salvo
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+using RDFSharp.Query;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace RDFSharp.Model
+{
+    /// <summary>
+    /// RDFXoneConstraint represents a SHACL constraint requiring exactly one of the given shapes for a given RDF term
+    /// </summary>
+    public class RDFXoneConstraint : RDFConstraint {
+
+        #region Properties
+        /// <summary>
+        /// Shapes required for the given RDF term
+        /// </summary>
+        internal Dictionary<Int64, RDFResource> XoneShapes { get; set; }
+        #endregion
+
+        #region Ctors
+        /// <summary>
+        /// Default-ctor to build a xone constraint
+        /// </summary>
+        public RDFXoneConstraint() : base() {
+            this.XoneShapes = new Dictionary<Int64, RDFResource>();
+        }
+        #endregion
+
+        #region Methods
+        /// <summary>
+        /// Adds the given shape to the required shapes of this constraint
+        /// </summary>
+        public RDFXoneConstraint AddShape(RDFResource shapeUri) {
+            if (shapeUri != null && !this.XoneShapes.ContainsKey(shapeUri.PatternMemberID)) {
+                this.XoneShapes.Add(shapeUri.PatternMemberID, shapeUri);
+            }
+            return this;
+        }
+
+        /// <summary>
+        /// Evaluates this constraint against the given data graph
+        /// </summary>
+        internal override RDFValidationReport ValidateConstraint(RDFShapesGraph shapesGraph, RDFGraph dataGraph, RDFShape shape, RDFPatternMember focusNode, List<RDFPatternMember> valueNodes) {
+            RDFValidationReport report = new RDFValidationReport();
+
+            //Search for given xone shapes
+            List<RDFShape> xoneShapes = new List<RDFShape>();
+            foreach (RDFResource xoneShapeUri in this.XoneShapes.Values) {
+                RDFShape xoneShape = shapesGraph.SelectShape(xoneShapeUri.ToString());
+                if (xoneShape != null)
+                    xoneShapes.Add(xoneShape);
+            }
+
+            #region Evaluation
+            foreach (RDFPatternMember valueNode in valueNodes) {
+                Int32 valueNodeConformsCounter = 0;
+                foreach (RDFShape xoneShape in xoneShapes) {
+                    RDFValidationReport xoneShapeReport = RDFValidationEngine.ValidateShape(shapesGraph, dataGraph, xoneShape, new List<RDFPatternMember>() { valueNode });
+                    if (xoneShapeReport.Conforms)
+                        valueNodeConformsCounter++;
+                }
+
+                if (valueNodeConformsCounter != 1)
+                    report.AddResult(new RDFValidationResult(shape,
+                                                             RDFVocabulary.SHACL.XONE_CONSTRAINT_COMPONENT,
+                                                             focusNode,
+                                                             shape is RDFPropertyShape ? ((RDFPropertyShape)shape).Path : null,
+                                                             valueNode,
+                                                             shape.Messages,
+                                                             shape.Severity));
+            }
+            #endregion
+
+            return report;
+        }
+
+        /// <summary>
+        /// Gets a graph representation of this constraint
+        /// </summary>
+        internal override RDFGraph ToRDFGraph(RDFShape shape) {
+            RDFGraph result = new RDFGraph();
+            if (shape != null) {
+
+                //Get collection from xoneShapes
+                RDFCollection xoneShapes = new RDFCollection(RDFModelEnums.RDFItemTypes.Resource) { InternalReificationSubject = this };
+                foreach (RDFResource xoneShape in this.XoneShapes.Values)
+                    xoneShapes.AddItem(xoneShape);
+                result.AddCollection(xoneShapes);
+
+                //sh:xone
+                result.AddTriple(new RDFTriple(shape, RDFVocabulary.SHACL.XONE, xoneShapes.ReificationSubject));
+
+            }
+            return result;
+        }
+        #endregion
+
+    }
+}

RDFSharp/Model/Validation/RDFValidationHelper.cs

@@ -203,6 +203,7 @@ private static RDFSelectQuery GetShapeQuery() {
                      .AddPattern(new RDFPattern(new RDFVariable("NSHAPE"), RDFVocabulary.SHACL.QUALIFIED_MIN_COUNT, new RDFVariable("QUALIFIEDMINCOUNT")).Optional())
                      .AddPattern(new RDFPattern(new RDFVariable("NSHAPE"), RDFVocabulary.SHACL.QUALIFIED_MAX_COUNT, new RDFVariable("QUALIFIEDMAXCOUNT")).Optional())
                      .AddPattern(new RDFPattern(new RDFVariable("NSHAPE"), RDFVocabulary.SHACL.UNIQUE_LANG, new RDFVariable("UNIQUELANG")).Optional())
+                     .AddPattern(new RDFPattern(new RDFVariable("NSHAPE"), RDFVocabulary.SHACL.XONE, new RDFVariable("XONE")).Optional())
                      .UnionWithNext()
                  )
                  .AddPatternGroup(new RDFPatternGroup("PROPERTYSHAPES")
@@ -255,6 +256,7 @@ private static RDFSelectQuery GetShapeQuery() {
                      .AddPattern(new RDFPattern(new RDFVariable("PSHAPE"), RDFVocabulary.SHACL.QUALIFIED_MIN_COUNT, new RDFVariable("QUALIFIEDMINCOUNT")).Optional())
                      .AddPattern(new RDFPattern(new RDFVariable("PSHAPE"), RDFVocabulary.SHACL.QUALIFIED_MAX_COUNT, new RDFVariable("QUALIFIEDMAXCOUNT")).Optional())
                      .AddPattern(new RDFPattern(new RDFVariable("PSHAPE"), RDFVocabulary.SHACL.UNIQUE_LANG, new RDFVariable("UNIQUELANG")).Optional())
+                     .AddPattern(new RDFPattern(new RDFVariable("PSHAPE"), RDFVocabulary.SHACL.XONE, new RDFVariable("XONE")).Optional())
                  );
         }
         private static RDFShape ParseShapeType(DataRow shapesRow) {
@@ -628,6 +630,19 @@ private static void ParseShapeConstraints(DataRow shapesRow, RDFGraph graph, RDF
                     shape.AddConstraint(new RDFUniqueLangConstraint(Boolean.Parse(((RDFTypedLiteral)uniqueLang).Value)));
             }
 
+            //sh:xone
+            if (!shapesRow.IsNull("?XONE")) {
+                RDFPatternMember reifSubj = RDFQueryUtilities.ParseRDFPatternMember(shapesRow.Field<string>("?XONE"));
+                if (reifSubj is RDFResource) {
+                    RDFXoneConstraint xoneConstraint = new RDFXoneConstraint();
+                    RDFCollection xoneColl = RDFModelUtilities.DeserializeCollectionFromGraph(graph, (RDFResource)reifSubj, RDFModelEnums.RDFTripleFlavors.SPO);
+                    xoneColl.Items.ForEach(item => {
+                        xoneConstraint.AddShape((RDFResource)item);
+                    });
+                    shape.AddConstraint(xoneConstraint);
+                }
+            }
+
         }
         private static void MergeShape(RDFShapesGraph result, RDFShape shape) {
             RDFShape existingShape = result.SelectShape(shape.ToString());