contract-policy within the transfer- sample

[ghost]

Hi,
I want to create a contract-policy within the transfer- sample, but I have some problems. I have created a "create-contract-policy" json-file with this context:

{
  "@context": {
    "edc": "https://w3id.org/edc/v0.0.1/ns/inForceDate",
    "@vocab": "http://www.w3.org/ns/odrl.jsonld"
  },
  "@type": "Offer",
  "@id": "time-limit-policy",
  "https://w3id.org/edc/v0.0.1/ns/policy": {
    "@context": "http://www.w3.org/ns/odrl.jsonld",
    "@type": "Set",
    "permission": [
      {
        "action": "use",
        "constraint": {
          "and": [
            {
              "leftOperand": "https://w3id.org/edc/v0.0.1/ns/inForceDate",
              "operator": "gte",
              "rightOperand": {
                "@value": "2024-05-06T00:00:01Z",
                "@type": "xsd:datetime"
              }
            },
            {
              "leftOperand": "https://w3id.org/edc/v0.0.1/ns/inForceDate",
              "operator": "lte",
              "rightOperand": {
                "@value": "2024-05-07T00:00:01Z",
                "@type": "xsd:datetime"
              }
            }
          ]
        }
      }
    ],
    "prohibition": [],
    "obligation": []
  }
}

My contract-policy specifies that the consumer is only allowed to use the data in a specific time. But If I try to create this policy on the provider's side and curl it with:

curl -d @transfer/transfer-01-negotiation/resources/create-contract-policy.json \
  -H 'content-type: application/json' http://localhost:19193/management/v2/policydefinitions \
  -s | jq

I get this output:

[
  {
    "message": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/permission/http://www.w3.org/ns/odrl/2/constraint/http://www.w3.org/ns/odrl/2/leftOperand is mandatory but missing or null",
    "type": "ValidationFailure",
    "path": "http://www.w3.org/ns/odrl/2/leftOperand",
    "invalidValue": null
  },
  {
    "message": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/permission/http://www.w3.org/ns/odrl/2/constraint/http://www.w3.org/ns/odrl/2/operator is mandatory but missing or null",
    "type": "ValidationFailure",
    "path": "http://www.w3.org/ns/odrl/2/operator",
    "invalidValue": null
  },
  {
    "message": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/permission/http://www.w3.org/ns/odrl/2/constraint/http://www.w3.org/ns/odrl/2/rightOperand is mandatory but missing or null",
    "type": "ValidationFailure",
    "path": "http://www.w3.org/ns/odrl/2/rightOperand",
    "invalidValue": null
  }
]

and these are my policy functions:

package org.eclipse.edc.sample.extension.policy;

import org.eclipse.edc.policy.engine.spi.PolicyEngine;
import org.eclipse.edc.policy.engine.spi.RuleBindingRegistry;
import org.eclipse.edc.policy.model.Permission;
import org.eclipse.edc.runtime.metamodel.annotation.Inject;
import org.eclipse.edc.spi.system.ServiceExtension;
import org.eclipse.edc.spi.system.ServiceExtensionContext;

import static org.eclipse.edc.connector.contract.spi.validation.ContractValidationService.NEGOTIATION_SCOPE;
import static org.eclipse.edc.jsonld.spi.PropertyAndTypeNames.ODRL_USE_ACTION_ATTRIBUTE;
import static org.eclipse.edc.policy.engine.spi.PolicyEngine.ALL_SCOPES;
import static org.eclipse.edc.spi.CoreConstants.EDC_NAMESPACE;

public class MyPolicyFunctionExtension implements ServiceExtension {
    private static final String TIME_LIMIT_CONSTRAINT_KEY = EDC_NAMESPACE + "timeLimit";

    @Inject
    private RuleBindingRegistry ruleBindingRegistry;

    @Inject
    private PolicyEngine policyEngine;

    @Override
    public String name() {
        return "Time-Limit Policy";
    }
    @Override
    public void initialize(ServiceExtensionContext context) {
        var monitor = context.getMonitor();

        ruleBindingRegistry.bind(ODRL_USE_ACTION_ATTRIBUTE, ALL_SCOPES);
        ruleBindingRegistry.bind(TIME_LIMIT_CONSTRAINT_KEY, NEGOTIATION_SCOPE);
        policyEngine.registerFunction(ALL_SCOPES, Permission.class, TIME_LIMIT_CONSTRAINT_KEY, new TimeConstraintFunction(monitor));    }
    }

package org.eclipse.edc.sample.extension.policy;

import org.eclipse.edc.policy.engine.spi.AtomicConstraintFunction;
import org.eclipse.edc.policy.engine.spi.PolicyContext;
import org.eclipse.edc.policy.model.Operator;
import org.eclipse.edc.policy.model.Permission;
import org.eclipse.edc.spi.monitor.Monitor;

import java.time.OffsetDateTime;
import java.time.format.DateTimeParseException;

public class TimeConstraintFunction implements AtomicConstraintFunction<Permission> {

    private final Monitor monitor;

    public TimeConstraintFunction(Monitor monitor) {
        this.monitor = monitor;
    }

    @Override
    public boolean evaluate(Operator operator, Object rightValue, Permission rule, PolicyContext context) {
        if (!(rightValue instanceof String)) {
            return false;
        }

        String timeString = (String) rightValue;
        try {
            OffsetDateTime rightTime = OffsetDateTime.parse(timeString);
            OffsetDateTime currentTime = OffsetDateTime.now();

            switch (operator.name()) { // Use operator name for comparison
                case "LTE":
                    return currentTime.compareTo(rightTime) <= 0;
                case "GTE":
                    return currentTime.compareTo(rightTime) >= 0;
                default:
                    return false;
            }
        } catch (DateTimeParseException e) {
            monitor.warning("Error parsing time constraint value: " + e.getMessage());
            return false;
        }
    }
}

Can anybody help me? Thanks

[ndr-brt]

Is this related to a specific sample? which one? which EDC version are you using?