Feat/dynamic odrl

demo/dynamic-policy.ts

@@ -0,0 +1,107 @@
+import { Parser, Writer } from 'n3';
+import { materializePolicy, ODRLEngineMultipleSteps, ODRLEvaluator, resourceToOptimisedTurtle } from "../dist/index";
+
+
+// Variant on test case 036: Read request from Alice to resource X returns into yes (temporal lt) (Alice Request Read X).
+// https://github.com/SolidLabResearch/ODRL-Test-Suite/blob/main/data/test_cases/testcase-036-alice-read-x.ttl
+const policy = `
+@prefix odrl: <http://www.w3.org/ns/odrl/2/> .
+@prefix ex: <http://example.org/> .
+@prefix dct: <http://purl.org/dc/terms/> .
+@prefix odrluc: <https://w3id.org/force/odrlproposed#> .
+
+<urn:uuid:32127a3f-5296-4cc6-b9d6-ef6c647a721d> a odrl:Set ;
+  odrl:uid <urn:uuid:32127a3f-5296-4cc6-b9d6-ef6c647a721d> ;
+  dct:description "ALICE may READ resource X when it is before 'ex:updateValue' (see sotw)." ;
+  dct:source <https://github.com/SolidLabResearch/ODRL-Test-Suite/> ;
+  odrl:permission <urn:uuid:d6ab4a38-68fb-418e-8af5-e77649a2187a> .
+
+<urn:uuid:d6ab4a38-68fb-418e-8af5-e77649a2187a> a odrl:Permission ;
+  odrl:assignee ex:alice ;
+  odrl:action odrl:read ;
+  odrl:target ex:x ;
+  odrl:constraint <urn:uuid:constraint:86526f9b-57c2-4c94-b079-9762fec562f1> .
+
+<urn:uuid:constraint:86526f9b-57c2-4c94-b079-9762fec562f1> odrl:leftOperand odrl:dateTime ;
+  odrl:operator odrl:lt ;
+  odrl:rightOperandReference ex:operandReference1 .
+
+ex:operandReference1 a odrluc:OperandReference ;
+    odrluc:reference ex:externalSource ;
+    odrluc:path ex:updatedValue .
+`
+
+// state of the world -> with external value indicating the time
+const sotw = `
+@prefix ex: <http://example.org/> .
+@prefix temp: <http://example.com/request/> .
+@prefix dct: <http://purl.org/dc/terms/> .
+
+<urn:uuid:192620fa-06d9-447b-adbd-bd1ece4f9b12> a ex:Sotw ;
+  ex:includes temp:currentTime .
+
+temp:currentTime dct:issued "2017-02-12T11:20:10.999Z"^^<http://www.w3.org/2001/XMLSchema#dateTime> .
+
+# external value that will be materialized in the policy
+ex:externalSource ex:updatedValue "2018-02-12T11:20:10.999Z"^^<http://www.w3.org/2001/XMLSchema#dateTime> .
+`
+
+const request = `
+@prefix odrl: <http://www.w3.org/ns/odrl/2/> .
+@prefix ex: <http://example.org/> .
+@prefix dct: <http://purl.org/dc/terms/> .
+
+<urn:uuid:1bafee59-006c-46a3-810c-5d176b4be364> a odrl:Request ;
+  odrl:uid <urn:uuid:1bafee59-006c-46a3-810c-5d176b4be364> ;
+  dct:description "Requesting Party ALICE requests to READ resource X." ;
+  odrl:permission <urn:uuid:186be541-5857-4ce3-9f03-1a274f16bf59> .
+
+<urn:uuid:186be541-5857-4ce3-9f03-1a274f16bf59> a odrl:Permission ;
+  odrl:assignee ex:alice ;
+  odrl:action odrl:read ;
+  odrl:target ex:x .
+`
+
+async function main() {
+  const parser = new Parser()
+  const writer = new Writer()
+
+  const odrlDynamicPolicyQuads = parser.parse(policy)
+
+  const odrlRequestQuads = parser.parse(request)
+  const stateOfTheWorldQuads = parser.parse(sotw)
+
+  const instantiatedPolicyQuads = materializePolicy(odrlDynamicPolicyQuads, stateOfTheWorldQuads)
+
+  console.log("Instantiated Policy:")
+  console.log(writer.quadsToString(instantiatedPolicyQuads));
+
+
+  // reasoning over dynamic policy
+  const evaluator = new ODRLEvaluator(new ODRLEngineMultipleSteps());
+  const reasoningResult = await evaluator.evaluate(
+    odrlDynamicPolicyQuads,
+    odrlRequestQuads,
+    stateOfTheWorldQuads)
+
+  const output = writer.quadsToString(reasoningResult);
+  console.log("Compliance Report")
+  console.log(output);
+
+      const prefixes = {
+          'odrl': 'http://www.w3.org/ns/odrl/2/',
+          'ex': 'http://example.org/',
+          'temp': 'http://example.com/request/',
+          'dct': 'http://purl.org/dc/terms/',
+          'xsd': 'http://www.w3.org/2001/XMLSchema#',
+          'foaf': 'http://xmlns.com/foaf/0.1/',
+          'report': 'https://w3id.org/force/compliance-report#'
+      }
+
+      // created report with N3
+      // @ts-ignore
+      console.log(resourceToOptimisedTurtle(reasoningResult, prefixes));
+
+}
+main()
+

package.json

@@ -17,6 +17,7 @@
     "clean": "rm -rf ./dist",
     "demo:test-engine": "ts-node demo/test-n3-engine.ts",
     "demo:test-evaluator": "ts-node demo/test-n3-evaluator.ts",
+    "demo:dynamic-policy": "ts-node demo/dynamic-policy.ts",
     "prepare": "npm run build",
     "release": "npm run build && npm publish --access public",
     "test": "jest"
@@ -39,8 +40,8 @@
     "@types/jest": "^29.5.12",
     "@types/tmp": "^0.2.6",
     "jest": "^29.7.0",
-    "ts-jest": "^29.2.5",
     "jest-rdf": "^2.0.0",
+    "ts-jest": "^29.2.5",
     "ts-node": "^10.9.2",
     "typescript": "^5.4.5"
   },
@@ -50,9 +51,10 @@
     "eyereasoner": "^16.18.4",
     "n3": "^1.20.4",
     "rdf-isomorphic": "^1.3.1",
+    "rdf-lens": "^1.3.5",
     "rdf-parse": "^3.0.0",
     "rdf-store-stream": "^2.0.1",
-    "rdf-vocabulary": "^1.0.0",
+    "rdf-vocabulary": "^1.0.1",
     "streamify-string": "^1.0.1",
     "tmp": "^0.2.3",
     "uuidv4": "^6.2.13"

src/evaluator/DynamicConstraint.ts

@@ -0,0 +1,66 @@
+import { Quad, Term } from "@rdfjs/types";
+import { Literal, NamedNode, Store } from 'n3';
+import { BasicLensM, CBDLens, Cont, pred, ShaclPath } from "rdf-lens";
+import { ODRL, ODRLUC, RDF } from "../util/Vocabularies";
+
+// use RDF lens instead of clownface for SHACL Property Paths: https://ceur-ws.org/Vol-3759/paper13.pdf
+export const pathLens = pred(ODRLUC.terms.path)
+  .one()
+  .then(ShaclPath);
+
+// Utility function to extract the SHACL property path of the Dynamic ODRL Policy using `odrluc:path`
+export function getPath(id: Term, quads: Quad[]): BasicLensM<Cont, Term> {
+  return pathLens.execute({ id, quads }).mapAll((x) => x.id);
+}
+
+// Utility function to extract the value from an external resource using a SHACL Property path
+export function usePath(id: Term, quads: Quad[], lens: BasicLensM<Cont, Term>): Term[] {
+  return lens.execute({ id, quads })
+}
+
+// implements dynamic policy constraint algorithm
+// algorithm to fetch value using SHACL path from sotw in policy
+// will only materialize when RightOperandReference class is present
+export function materializePolicy(dynamicPolicy: Quad[], stateOfTheWorld: Quad[]): Quad[] {
+    const odrlPolicyStore = new Store(dynamicPolicy)
+    const odrlDynamicPolicyStore = new Store(dynamicPolicy)
+
+    // get all constraints containing references
+    const operandReferenceNodes = odrlDynamicPolicyStore.getSubjects(RDF.terms.type, ODRLUC.terms.OperandReference, null);
+
+    for (const operandReferenceNode of operandReferenceNodes) {
+      // ODRL constraint that has that given rightOperandReference
+      const constraintNodes = odrlDynamicPolicyStore.getSubjects(ODRL.terms.rightOperandReference, operandReferenceNode, null)
+
+      // external resource
+      const externalResource = odrlDynamicPolicyStore.getObjects(operandReferenceNode, ODRLUC.terms.reference, null)[0]
+      if (!externalResource) { 
+          throw Error("There is no source present in the Dynamic Policy Constraint.")
+      }
+
+      // SHACL Property path
+      const lens = getPath(operandReferenceNode, dynamicPolicy); 
+
+      // extract SHACL Property Path using RDF-Lens
+      const getValue = usePath(externalResource, stateOfTheWorld, lens);
+      const instantiatedValue = getValue[0]; // according to the algorithm (see paper), there should be only one term
+
+      if (!(instantiatedValue instanceof NamedNode || instantiatedValue instanceof Literal)) {
+          // Now instantiatedValue is a valid value
+          throw Error("Instantiated value is not a proper value.");
+      }
+      for (const constraintNode of constraintNodes) {
+        // remove rightOperandRefrence triple from constraint
+        odrlPolicyStore.removeQuad(constraintNode, ODRL.terms.rightOperandReference, operandReferenceNode)
+        // add materialized rightOperand
+        odrlPolicyStore.addQuad(constraintNode, ODRL.terms.rightOperand, instantiatedValue)
+      }
+
+      // remove OperandReference triples from Policy store
+      const operandReferenceQuads = CBDLens.execute({id:operandReferenceNode, quads: dynamicPolicy})
+      odrlPolicyStore.removeQuads(operandReferenceQuads)
+    }
+    return odrlPolicyStore.getQuads(null, null, null, null)
+  }
+
+

src/evaluator/Evaluate.ts

@@ -1,6 +1,7 @@
 import type { Quad } from '@rdfjs/types';
 import { ODRLEngine, Engine} from './Engine';
 import { RDFValidator, TripleTermValidator, SHACLValidator } from './Validate';
+import { materializePolicy } from './DynamicConstraint';
 
 export interface Evaluator {
     /**
@@ -64,9 +65,11 @@ export class ODRLEvaluator implements Evaluator {
 
         // if there are compact policies -> they must be expanded (also reocmmended by ODRL § 2.7.1 Compact Policy)
 
+        // handle dynamic policies
+        const instantiatedPolicies = materializePolicy(policy, state);
         // evaluate
         // the evaluation will result into a conformance report
-        const evaluation = await this.engine.evaluate([...policy, ...request, ...state])
+        const evaluation = await this.engine.evaluate([...instantiatedPolicies, ...request, ...state])
 
         // TODO: think about when the report can be empty
         // does it always mean there is not enough information?

src/index.browser.ts

@@ -1,11 +1 @@
-export * from './evaluator/Engine'
-export * from './evaluator/Evaluate'
-export * from './evaluator/Validate'
-
-export * from './reasoner/EyeJsReasoner'
-// export * from './reasoner/EyeReasoner'
-export * from './reasoner/Reasoner'
-
-export * from './util/Notation3Util'
-// export * from './util/RDFUtil'
-export * from './rules/Rules'
+export * from "./index.core"

src/index.core.ts

@@ -0,0 +1,12 @@
+export * from './evaluator/Engine'
+export * from './evaluator/Evaluate'
+export * from './evaluator/Validate'
+export * from './evaluator/DynamicConstraint'
+
+export * from './reasoner/EyeJsReasoner'
+export * from './reasoner/Reasoner'
+
+export * from './util/Notation3Util'
+export * from './util/Vocabularies'
+
+export * from './rules/Rules'

src/index.ts

@@ -1,10 +1,4 @@
-export * from './evaluator/Engine'
-export * from './evaluator/Evaluate'
-export * from './evaluator/Validate'
-
-export * from './reasoner/EyeJsReasoner'
+export * from "./index.core"
 export * from './reasoner/EyeReasoner'
-export * from './reasoner/Reasoner'
 
-export * from './util/Notation3Util'
 export * from './util/RDFUtil'

src/reasoner/EyeJsReasoner.ts

@@ -1,4 +1,4 @@
-import { n3reasoner } from "eyereasoner/dist";
+import { n3reasoner } from "eyereasoner";
 import { Reasoner } from "./Reasoner";
 
 export class EyeJsReasoner extends Reasoner {