Issue 4426 add sorting to mdm queries (#4439)

* Add sorting capability to $mdm-query-links operation

* Add exception code

* Improve code

* Add test combining pagination with sort

Co-authored-by: juan.marchionatto <juan.marchionatto@smilecdr.com>

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/6_4_0/4426-add-sort-capability-to-mdm-query-links-operation.yaml

@@ -0,0 +1,4 @@
+---
+type: add
+issue: 4426
+title: "Added sorting capability to $mdm-query-links operation."

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/docs/server_jpa_mdm/mdm_operations.md

@@ -113,6 +113,14 @@ Use the `$mdm-query-links` operation to view MDM links. The results returned are
                 The number of links to be returned in a page. 
             </td>
         </tr>
+        <tr>
+            <td>_sort</td>
+            <td>String</td>
+            <td>0..1</td>
+            <td>
+                The sort specification (see sort note below). 
+            </td>
+        </tr>
         <tr>
             <td>resourceType</td>
             <td>String</td>
@@ -124,6 +132,12 @@ Use the `$mdm-query-links` operation to view MDM links. The results returned are
     </tbody>
 </table>
 
+Sort note: sort is specified by adding one or more comma-separated MdmLink property names prefixed by '-' (minus sign) to indicate descending order. 
+
+#### Sort specification example
+```url
+http://example.com/$mdm-query-links?_sort=-myScore,myCreated
+```
 ### Example
 
 Use an HTTP GET like `http://example.com/$mdm-query-links?matchResult=POSSIBLE_MATCH` or an HTTP POST to the following URL to invoke this operation:

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/mdm/MdmLinkDaoJpaImpl.java

@@ -33,6 +33,7 @@ import ca.uhn.fhir.mdm.api.MdmQuerySearchParameters;
 import ca.uhn.fhir.mdm.api.paging.MdmPageRequest;
 import ca.uhn.fhir.mdm.dao.IMdmLinkDao;
 import ca.uhn.fhir.mdm.model.MdmPidTuple;
+import ca.uhn.fhir.rest.api.SortOrderEnum;
 import ca.uhn.fhir.rest.server.exceptions.UnprocessableEntityException;
 import org.apache.commons.collections4.CollectionUtils;
 import org.apache.commons.collections4.ListUtils;
@@ -49,14 +50,26 @@ import javax.persistence.TypedQuery;
 import javax.persistence.criteria.CriteriaBuilder;
 import javax.persistence.criteria.CriteriaQuery;
 import javax.persistence.criteria.Expression;
+import javax.persistence.criteria.Order;
+import javax.persistence.criteria.Path;
 import javax.persistence.criteria.Predicate;
 import javax.persistence.criteria.Root;
+import javax.validation.constraints.NotNull;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.GOLDEN_RESOURCE_NAME;
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.GOLDEN_RESOURCE_PID_NAME;
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.LINK_SOURCE_NAME;
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.MATCH_RESULT_NAME;
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.PARTITION_ID_NAME;
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.RESOURCE_TYPE_NAME;
+import static ca.uhn.fhir.mdm.api.MdmQuerySearchParameters.SOURCE_PID_NAME;
+
 public class MdmLinkDaoJpaImpl implements IMdmLinkDao<JpaPid, MdmLink> {
 	@Autowired
 	IMdmLinkJpaRepository myMdmLinkDao;
@@ -107,7 +120,7 @@ public class MdmLinkDaoJpaImpl implements IMdmLinkDao<JpaPid, MdmLink> {
 	public List<JpaPid> findPidByResourceNameAndThreshold(String theResourceName, Date theHighThreshold, Pageable thePageable) {
 		return myMdmLinkDao.findPidByResourceNameAndThreshold(theResourceName,theHighThreshold, thePageable)
 			.stream()
-			.map( theResourcePids -> JpaPid.fromId(theResourcePids))
+			.map(JpaPid::fromId)
 			.collect(Collectors.toList());
 	}
 
@@ -115,7 +128,7 @@ public class MdmLinkDaoJpaImpl implements IMdmLinkDao<JpaPid, MdmLink> {
 	public List<JpaPid> findPidByResourceNameAndThresholdAndPartitionId(String theResourceName, Date theHighThreshold, List<Integer> thePartitionIds, Pageable thePageable) {
 		return myMdmLinkDao.findPidByResourceNameAndThresholdAndPartitionId(theResourceName,theHighThreshold, thePartitionIds, thePageable)
 			.stream()
-			.map( theResourcePids -> JpaPid.fromId(theResourcePids))
+			.map(JpaPid::fromId)
 			.collect(Collectors.toList());
 	}
 
@@ -183,8 +196,14 @@ public class MdmLinkDaoJpaImpl implements IMdmLinkDao<JpaPid, MdmLink> {
 
 	@Override
 	@Deprecated
-	public Page<MdmLink> search(IIdType theGoldenResourceId, IIdType theSourceId, MdmMatchResultEnum theMatchResult, MdmLinkSourceEnum theLinkSource, MdmPageRequest thePageRequest, List<Integer> thePartitionId) {
+	public Page<MdmLink> search(IIdType theGoldenResourceId, IIdType theSourceId, MdmMatchResultEnum theMatchResult,
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(theGoldenResourceId, theSourceId, theMatchResult, theLinkSource, thePageRequest, thePartitionId, null);
+										 MdmLinkSourceEnum theLinkSource, MdmPageRequest thePageRequest, List<Integer> thePartitionIds) {
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setGoldenResourceId(theGoldenResourceId)
+			.setSourceId(theSourceId)
+			.setMatchResult(theMatchResult)
+			.setLinkSource(theLinkSource)
+			.setPartitionIds(thePartitionIds);
 		return search(mdmQuerySearchParameters);
 	}
 
@@ -193,37 +212,14 @@ public class MdmLinkDaoJpaImpl implements IMdmLinkDao<JpaPid, MdmLink> {
 		CriteriaBuilder criteriaBuilder = myEntityManager.getCriteriaBuilder();
 		CriteriaQuery<MdmLink> criteriaQuery = criteriaBuilder.createQuery(MdmLink.class);
 		Root<MdmLink> from = criteriaQuery.from(MdmLink.class);
+		List<Order> orderList = getOrderList(theParams, criteriaBuilder, from);
 
-		List<Predicate> andPredicates = new ArrayList<>();
+		List<Predicate> andPredicates = buildPredicates(theParams, criteriaBuilder, from);
-
-		if (theParams.getGoldenResourceId() != null) {
-			Predicate goldenResourcePredicate = criteriaBuilder.equal(from.get("myGoldenResourcePid").as(Long.class), (myIdHelperService.getPidOrThrowException(RequestPartitionId.allPartitions(), theParams.getGoldenResourceId())).getId());
-			andPredicates.add(goldenResourcePredicate);
-		}
-		if (theParams.getSourceId() != null) {
-			Predicate sourceIdPredicate = criteriaBuilder.equal(from.get("mySourcePid").as(Long.class), (myIdHelperService.getPidOrThrowException(RequestPartitionId.allPartitions(), theParams.getSourceId())).getId());
-			andPredicates.add(sourceIdPredicate);
-		}
-		if (theParams.getMatchResult() != null) {
-			Predicate matchResultPredicate = criteriaBuilder.equal(from.get("myMatchResult").as(MdmMatchResultEnum.class), theParams.getMatchResult());
-			andPredicates.add(matchResultPredicate);
-		}
-		if (theParams.getLinkSource() != null) {
-			Predicate linkSourcePredicate = criteriaBuilder.equal(from.get("myLinkSource").as(MdmLinkSourceEnum.class), theParams.getLinkSource());
-			andPredicates.add(linkSourcePredicate);
-		}
-		if (!CollectionUtils.isEmpty(theParams.getPartitionIds())) {
-			Expression<Integer> exp = from.get("myPartitionId").get("myPartitionId").as(Integer.class);
-			Predicate linkSourcePredicate = exp.in(theParams.getPartitionIds());
-			andPredicates.add(linkSourcePredicate);
-		}
-
-		if (theParams.getResourceType() != null) {
-			Predicate resourceTypePredicate = criteriaBuilder.equal(from.get("myGoldenResource").get("myResourceType").as(String.class), theParams.getResourceType());
-			andPredicates.add(resourceTypePredicate);
-		}
 
 		Predicate finalQuery = criteriaBuilder.and(andPredicates.toArray(new Predicate[0]));
+		if ( ! orderList.isEmpty()) {
+			criteriaQuery.orderBy(orderList);
+		}
 		TypedQuery<MdmLink> typedQuery = myEntityManager.createQuery(criteriaQuery.where(finalQuery));
 
 		CriteriaQuery<Long> countQuery = criteriaBuilder.createQuery(Long.class);
@@ -232,11 +228,63 @@ public class MdmLinkDaoJpaImpl implements IMdmLinkDao<JpaPid, MdmLink> {
 
 		Long totalResults = myEntityManager.createQuery(countQuery).getSingleResult();
 		MdmPageRequest pageRequest = theParams.getPageRequest();
-		return new PageImpl<>(typedQuery.setFirstResult(pageRequest.getOffset()).setMaxResults(pageRequest.getCount()).getResultList(),
+
+		List<MdmLink> result = typedQuery
+			.setFirstResult(pageRequest.getOffset())
+			.setMaxResults(pageRequest.getCount())
+			.getResultList();
+
+		return new PageImpl<>(result,
 			PageRequest.of(pageRequest.getPage(), pageRequest.getCount()),
 			totalResults);
 	}
 
+	@NotNull
+	private List<Predicate> buildPredicates(MdmQuerySearchParameters theParams, CriteriaBuilder criteriaBuilder, Root<MdmLink> from) {
+		List<Predicate> andPredicates = new ArrayList<>();
+		if (theParams.getGoldenResourceId() != null) {
+			Predicate goldenResourcePredicate = criteriaBuilder.equal(from.get(GOLDEN_RESOURCE_PID_NAME).as(Long.class), (myIdHelperService.getPidOrThrowException(RequestPartitionId.allPartitions(), theParams.getGoldenResourceId())).getId());
+			andPredicates.add(goldenResourcePredicate);
+		}
+		if (theParams.getSourceId() != null) {
+			Predicate sourceIdPredicate = criteriaBuilder.equal(from.get(SOURCE_PID_NAME).as(Long.class), (myIdHelperService.getPidOrThrowException(RequestPartitionId.allPartitions(), theParams.getSourceId())).getId());
+			andPredicates.add(sourceIdPredicate);
+		}
+		if (theParams.getMatchResult() != null) {
+			Predicate matchResultPredicate = criteriaBuilder.equal(from.get(MATCH_RESULT_NAME).as(MdmMatchResultEnum.class), theParams.getMatchResult());
+			andPredicates.add(matchResultPredicate);
+		}
+		if (theParams.getLinkSource() != null) {
+			Predicate linkSourcePredicate = criteriaBuilder.equal(from.get(LINK_SOURCE_NAME).as(MdmLinkSourceEnum.class), theParams.getLinkSource());
+			andPredicates.add(linkSourcePredicate);
+		}
+		if (!CollectionUtils.isEmpty(theParams.getPartitionIds())) {
+			Expression<Integer> exp = from.get(PARTITION_ID_NAME).get(PARTITION_ID_NAME).as(Integer.class);
+			Predicate linkSourcePredicate = exp.in(theParams.getPartitionIds());
+			andPredicates.add(linkSourcePredicate);
+		}
+
+		if (theParams.getResourceType() != null) {
+			Predicate resourceTypePredicate = criteriaBuilder.equal(from.get(GOLDEN_RESOURCE_NAME).get(RESOURCE_TYPE_NAME).as(String.class), theParams.getResourceType());
+			andPredicates.add(resourceTypePredicate);
+		}
+
+		return andPredicates;
+	}
+
+
+	private List<Order> getOrderList(MdmQuerySearchParameters theParams, CriteriaBuilder criteriaBuilder, Root<MdmLink> from) {
+		if (CollectionUtils.isEmpty(theParams.getSort())) {
+			return Collections.emptyList();
+		}
+
+		return theParams.getSort().stream().map(sortSpec -> {
+				Path<Object> path = from.get(sortSpec.getParamName());
+				return sortSpec.getOrder() == SortOrderEnum.DESC ? criteriaBuilder.desc(path) : criteriaBuilder.asc(path);
+			})
+			.collect(Collectors.toList());
+	}
+
 	@Override
 	public Optional<MdmLink> findBySourcePidAndMatchResult(JpaPid theSourcePid, MdmMatchResultEnum theMatch) {
 		return myMdmLinkDao.findBySourcePidAndMatchResult((theSourcePid).getId(), theMatch);

hapi-fhir-jpaserver-mdm/src/main/java/ca/uhn/fhir/jpa/mdm/svc/MdmControllerSvcImpl.java

@@ -103,14 +103,24 @@ public class MdmControllerSvcImpl implements IMdmControllerSvc {
 	@Override
 	@Deprecated
 	public Page<MdmLinkJson> queryLinks(@Nullable String theGoldenResourceId, @Nullable String theSourceResourceId, @Nullable String theMatchResult, @Nullable String theLinkSource, MdmTransactionContext theMdmTransactionContext, MdmPageRequest thePageRequest) {
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(theGoldenResourceId, theSourceResourceId, theMatchResult, theLinkSource, thePageRequest, null, null);
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setGoldenResourceId(theGoldenResourceId)
+			.setSourceId(theSourceResourceId)
+			.setMatchResult(theMatchResult)
+			.setLinkSource(theLinkSource);
 		return queryLinksFromPartitionList(mdmQuerySearchParameters, theMdmTransactionContext);
 	}
 
 	@Override
 	@Deprecated
-	public Page<MdmLinkJson> queryLinks(@Nullable String theGoldenResourceId, @Nullable String theSourceResourceId, @Nullable String theMatchResult, @Nullable String theLinkSource, MdmTransactionContext theMdmTransactionContext, MdmPageRequest thePageRequest, @Nullable RequestDetails theRequestDetails) {
+	public Page<MdmLinkJson> queryLinks(@Nullable String theGoldenResourceId, @Nullable String theSourceResourceId,
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(theGoldenResourceId, theSourceResourceId, theMatchResult, theLinkSource, thePageRequest, null, null);
+													@Nullable String theMatchResult, @Nullable String theLinkSource, MdmTransactionContext theMdmTransactionContext,
+													MdmPageRequest thePageRequest, @Nullable RequestDetails theRequestDetails) {
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setGoldenResourceId(theGoldenResourceId)
+			.setSourceId(theSourceResourceId)
+			.setMatchResult(theMatchResult)
+			.setLinkSource(theLinkSource);
 		return queryLinks(mdmQuerySearchParameters, theMdmTransactionContext, theRequestDetails);
 	}
 
@@ -130,8 +140,16 @@ public class MdmControllerSvcImpl implements IMdmControllerSvc {
 
 	@Override
 	@Deprecated
-	public Page<MdmLinkJson> queryLinksFromPartitionList(@Nullable String theGoldenResourceId, @Nullable String theSourceResourceId, @Nullable String theMatchResult, @Nullable String theLinkSource, MdmTransactionContext theMdmTransactionContext, MdmPageRequest thePageRequest, @Nullable List<Integer> thePartitionIds) {
+	public Page<MdmLinkJson> queryLinksFromPartitionList(@Nullable String theGoldenResourceId, @Nullable String theSourceResourceId,
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(theGoldenResourceId, theSourceResourceId, theMatchResult, theLinkSource, thePageRequest, thePartitionIds, null);
+																		  @Nullable String theMatchResult, @Nullable String theLinkSource,
+																		  MdmTransactionContext theMdmTransactionContext, MdmPageRequest thePageRequest,
+																		  @Nullable List<Integer> thePartitionIds) {
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setGoldenResourceId(theGoldenResourceId)
+			.setSourceId(theSourceResourceId)
+			.setMatchResult(theMatchResult)
+			.setLinkSource(theLinkSource)
+			.setPartitionIds(thePartitionIds);
 		return queryLinksFromPartitionList(mdmQuerySearchParameters, theMdmTransactionContext);
 	}
 
@@ -214,7 +232,6 @@ public class MdmControllerSvcImpl implements IMdmControllerSvc {
 		if (theBatchSize != null && theBatchSize.getValue() !=null && theBatchSize.getValue().longValue() > 0) {
 			params.setBatchSize(theBatchSize.getValue().intValue());
 		}
-		ReadPartitionIdRequestDetails details= new ReadPartitionIdRequestDetails(null, RestOperationTypeEnum.EXTENDED_OPERATION_SERVER, null, null, null);
 		params.setRequestPartitionId(RequestPartitionId.allPartitions());
 
 		theUrls.forEach(params::addUrl);

hapi-fhir-jpaserver-mdm/src/main/java/ca/uhn/fhir/jpa/mdm/svc/MdmLinkQuerySvcImplSvc.java

@@ -52,21 +52,33 @@ public class MdmLinkQuerySvcImplSvc implements IMdmLinkQuerySvc {
 	@Deprecated
 	@Transactional
 	public Page<MdmLinkJson> queryLinks(IIdType theGoldenResourceId, IIdType theSourceResourceId, MdmMatchResultEnum theMatchResult, MdmLinkSourceEnum theLinkSource, MdmTransactionContext theMdmContext, MdmPageRequest thePageRequest) {
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(theGoldenResourceId, theSourceResourceId, theMatchResult, theLinkSource, thePageRequest, null, null);
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setGoldenResourceId(theGoldenResourceId)
+			.setSourceId(theSourceResourceId)
+			.setMatchResult(theMatchResult)
+			.setLinkSource(theLinkSource);
+
 		return queryLinks(mdmQuerySearchParameters, theMdmContext);
 	}
 
 	@Override
 	@Deprecated
 	@Transactional
-	public Page<MdmLinkJson> queryLinks(IIdType theGoldenResourceId, IIdType theSourceResourceId, MdmMatchResultEnum theMatchResult, MdmLinkSourceEnum theLinkSource, MdmTransactionContext theMdmContext, MdmPageRequest thePageRequest, List<Integer> thePartitionId) {
+	public Page<MdmLinkJson> queryLinks(IIdType theGoldenResourceId, IIdType theSourceResourceId, MdmMatchResultEnum theMatchResult, MdmLinkSourceEnum theLinkSource, MdmTransactionContext theMdmContext, MdmPageRequest thePageRequest, List<Integer> thePartitionIds) {
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(theGoldenResourceId, theSourceResourceId, theMatchResult, theLinkSource, thePageRequest, thePartitionId, null);
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setGoldenResourceId(theGoldenResourceId)
+			.setSourceId(theSourceResourceId)
+			.setMatchResult(theMatchResult)
+			.setLinkSource(theLinkSource)
+			.setPartitionIds(thePartitionIds);
+
 		return queryLinks(mdmQuerySearchParameters, theMdmContext);
 	}
 
 	@Override
 	@Transactional
 	public Page<MdmLinkJson> queryLinks(MdmQuerySearchParameters theMdmQuerySearchParameters, MdmTransactionContext theMdmContext) {
+		@SuppressWarnings("unchecked")
 		Page<? extends IMdmLink> mdmLinks = myMdmLinkDaoSvc.executeTypedQuery(theMdmQuerySearchParameters);
 		return mdmLinks.map(myMdmModelConverterSvc::toJson);
 	}
@@ -80,9 +92,14 @@ public class MdmLinkQuerySvcImplSvc implements IMdmLinkQuerySvc {
 
 	@Override
 	@Transactional
-	public Page<MdmLinkJson> getDuplicateGoldenResources(MdmTransactionContext theMdmContext, MdmPageRequest thePageRequest, List<Integer> thePartitionId, String theRequestResourceType) {
+	public Page<MdmLinkJson> getDuplicateGoldenResources(MdmTransactionContext theMdmContext, MdmPageRequest thePageRequest,
-		MdmQuerySearchParameters mdmQuerySearchParameters =
+																		  List<Integer> thePartitionIds, String theRequestResourceType) {
-			new MdmQuerySearchParameters(null, null, MdmMatchResultEnum.POSSIBLE_DUPLICATE, null, thePageRequest, thePartitionId, theRequestResourceType);
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(thePageRequest)
+			.setMatchResult(MdmMatchResultEnum.POSSIBLE_DUPLICATE)
+			.setPartitionIds(thePartitionIds)
+			.setResourceType(theRequestResourceType);
+
+		@SuppressWarnings("unchecked")
 		Page<? extends IMdmLink> mdmLinkPage = myMdmLinkDaoSvc.executeTypedQuery(mdmQuerySearchParameters);
 		return mdmLinkPage.map(myMdmModelConverterSvc::toJson);
 	}

hapi-fhir-jpaserver-mdm/src/test/java/ca/uhn/fhir/jpa/mdm/provider/MdmProviderQueryLinkR4Test.java

@@ -10,23 +10,30 @@ import ca.uhn.fhir.mdm.api.MdmMatchResultEnum;
 import ca.uhn.fhir.model.primitive.IdDt;
 import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException;
 import ca.uhn.fhir.rest.server.exceptions.ResourceNotFoundException;
+import ca.uhn.fhir.util.ParametersUtil;
 import ca.uhn.fhir.util.StopWatch;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.tuple.Pair;
 import org.hl7.fhir.dstu3.model.UnsignedIntType;
 import org.hl7.fhir.instance.model.api.IAnyResource;
+import org.hl7.fhir.instance.model.api.IBase;
 import org.hl7.fhir.instance.model.api.IIdType;
 import org.hl7.fhir.r4.model.BooleanType;
+import org.hl7.fhir.r4.model.DecimalType;
 import org.hl7.fhir.r4.model.IdType;
 import org.hl7.fhir.r4.model.Parameters;
 import org.hl7.fhir.r4.model.Patient;
 import org.hl7.fhir.r4.model.StringType;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 
+import java.util.Comparator;
 import java.util.List;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -35,13 +42,16 @@ import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.lessThanOrEqualTo;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assertions.fail;
 
 public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 	private static final Logger ourLog = LoggerFactory.getLogger(MdmProviderQueryLinkR4Test.class);
+	private static final int MDM_LINK_PROPERTY_COUNT = 9;
 	private static final StringType RESOURCE_TYPE_PATIENT = new StringType("Patient");
 	private static final StringType RESOURCE_TYPE_OBSERVATION = new StringType("Observation");
+
 	private StringType myLinkSource;
 	private StringType myGoldenResource1Id;
 	private StringType myGoldenResource2Id;
@@ -74,27 +84,180 @@ public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 
 	@Test
 	public void testQueryLinkOneMatch() {
-		Parameters result = (Parameters) myMdmProvider.queryLinks(mySourcePatientId, myPatientId, null, null, new UnsignedIntType(0), new UnsignedIntType(10), myRequestDetails, null);
+		Parameters result = (Parameters) myMdmProvider.queryLinks(mySourcePatientId, myPatientId, null, null, new UnsignedIntType(0), new UnsignedIntType(10), new StringType(), myRequestDetails, null);
 		ourLog.debug(myFhirContext.newJsonParser().setPrettyPrint(true).encodeResourceToString(result));
 		List<Parameters.ParametersParameterComponent> list = getParametersByName(result, "link");
 		assertThat(list, hasSize(1));
 		List<Parameters.ParametersParameterComponent> part = list.get(0).getPart();
-		assertMdmLink(7, part, mySourcePatientId.getValue(), myPatientId.getValue(), MdmMatchResultEnum.POSSIBLE_MATCH, "false", "true", null);
+		assertMdmLink(MDM_LINK_PROPERTY_COUNT, part, mySourcePatientId.getValue(), myPatientId.getValue(), MdmMatchResultEnum.POSSIBLE_MATCH, "false", "true", null);
 	}
 
 	@Test
 	public void testQueryLinkWithResourceType() {
-		Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null, new UnsignedIntType(0), new UnsignedIntType(10), myRequestDetails, RESOURCE_TYPE_PATIENT);
+		Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null, new UnsignedIntType(0), new UnsignedIntType(10), new StringType(), myRequestDetails, RESOURCE_TYPE_PATIENT);
 		ourLog.debug(myFhirContext.newJsonParser().setPrettyPrint(true).encodeResourceToString(result));
 		List<Parameters.ParametersParameterComponent> list = getParametersByName(result, "link");
 		assertThat("All resources with Patient type found", list, hasSize(3));
 		List<Parameters.ParametersParameterComponent> part = list.get(0).getPart();
-		assertMdmLink(7, part, mySourcePatientId.getValue(), myPatientId.getValue(), MdmMatchResultEnum.POSSIBLE_MATCH, "false", "true", null);
+		assertMdmLink(MDM_LINK_PROPERTY_COUNT, part, mySourcePatientId.getValue(), myPatientId.getValue(), MdmMatchResultEnum.POSSIBLE_MATCH, "false", "true", null);
 	}
 
+
+	@Nested
+	public class QueryLinkWithSort {
+		@Test
+		public void byCreatedDescending() {
+			Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null,
+				new UnsignedIntType(0), new UnsignedIntType(10), new StringType("-myCreated"),
+				myRequestDetails, new StringType("Patient"));
+
+			List<Parameters.ParametersParameterComponent> linkList = getParametersByName(result, "link");
+			assertThat(linkList, hasSize(3));
+
+			List<Long> createdDates = linkList.stream().map(this::extractCreated).collect(Collectors.toList());
+
+			// by created descending
+			Comparator<Long> comp = Comparator.comparingLong( (Long e) -> e).reversed();
+			List<Long> expected = createdDates.stream().sorted(comp).collect(Collectors.toList());
+
+			assertEquals(expected, createdDates);
+		}
+
+		@Test
+		public void byScoreDescending() {
+			addScoresToLinksInCreationOrder(List.of(.5d, .1d, .3d));
+
+			Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null,
+				new UnsignedIntType(0), new UnsignedIntType(10), new StringType("-myScore"),
+				myRequestDetails, new StringType("Patient"));
+
+			List<Parameters.ParametersParameterComponent> linkList = getParametersByName(result, "link");
+			assertThat(linkList, hasSize(3));
+
+			List<Double> scores = linkList.stream().map(this::extractScore).collect(Collectors.toList());
+
+			// by score descending
+			Comparator<Double> comp = Comparator.comparingDouble( (Double e) -> e).reversed();
+			List<Double> expected = scores.stream().sorted(comp).collect(Collectors.toList());
+
+			assertEquals(expected, scores);
+		}
+
+
+		@Test
+		public void byScoreDescendingAndThenCreated() {
+			addScoresToLinksInCreationOrder(List.of(.4d, .4d, .3d));
+
+			Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null,
+				new UnsignedIntType(0), new UnsignedIntType(10), new StringType("-myScore,-myCreated"),
+				myRequestDetails, new StringType("Patient"));
+
+			List<Parameters.ParametersParameterComponent> linkList = getParametersByName(result, "link");
+			assertThat(linkList, hasSize(3));
+
+			List<Pair<Long, Double>> resultUpdatedScorePairs = linkList.stream()
+				.map(l -> Pair.of(extractCreated(l), extractScore(l))).collect(Collectors.toList());
+
+			// by desc score then desc created
+			Comparator<Pair<Long, Double>> comp = Comparator
+				.comparing( (Pair<Long, Double> p) -> p.getRight(), Comparator.reverseOrder() )
+				.thenComparing(Pair::getLeft, Comparator.reverseOrder() );
+
+			List<Pair<Long, Double>> expected = resultUpdatedScorePairs.stream().sorted(comp).collect(Collectors.toList());
+
+			assertEquals(expected, resultUpdatedScorePairs);
+		}
+
+		@Test
+		public void testPaginationWhenSorting() {
+			addTwoMoreMdmLinks();
+			addScoresToLinksInCreationOrder(List.of(.5d, .1d, .3d, .8d, .6d));
+			List<Double> expectedScoresPage1 = List.of(.8d, .6d, .5d);
+			List<Double> expectedScoresPage2 = List.of(.3d, .1d);
+
+			int pageSize = 3;
+
+			// first page
+
+			Parameters page1 = (Parameters) myMdmProvider.queryLinks(null, null, null, null,
+				new UnsignedIntType(0), new UnsignedIntType(pageSize), new StringType("-myScore"),
+				myRequestDetails, new StringType("Patient"));
+
+			List<Parameters.ParametersParameterComponent> linkListPage1 = getParametersByName(page1, "link");
+			assertThat(linkListPage1, hasSize(pageSize));
+
+			List<Double> scoresPage1 = linkListPage1.stream().map(this::extractScore).collect(Collectors.toList());
+			assertEquals(expectedScoresPage1, scoresPage1);
+
+			// second page
+
+			Parameters page2 = (Parameters) myMdmProvider.queryLinks(null, null, null, null,
+				new UnsignedIntType(pageSize), new UnsignedIntType(pageSize), new StringType("-myScore"),
+				myRequestDetails, new StringType("Patient"));
+
+			List<Parameters.ParametersParameterComponent> linkListPage2 = getParametersByName(page2, "link");
+			assertThat(linkListPage2, hasSize(2));
+
+			List<Double> scoresPage2 = linkListPage2.stream().map(this::extractScore).collect(Collectors.toList());
+			assertEquals(expectedScoresPage2, scoresPage2);
+		}
+
+
+		private Long extractCreated(Parameters.ParametersParameterComponent theParamComponent) {
+			Optional<IBase> opt = ParametersUtil.getParameterPartValue(myFhirContext, theParamComponent, "linkUpdated");
+			assertTrue(opt.isPresent());
+			DecimalType createdDateDt = (DecimalType) opt.get();
+			return createdDateDt.getValue().longValue();
+		}
+
+
+		private Double extractScore(Parameters.ParametersParameterComponent theParamComponent) {
+			Optional<IBase> opt = ParametersUtil.getParameterPartValue(myFhirContext, theParamComponent, "score");
+			assertTrue(opt.isPresent());
+			DecimalType scoreIntegerDt = (DecimalType) opt.get();
+			assertNotNull(scoreIntegerDt.getValue());
+			return scoreIntegerDt.getValue().doubleValue();
+		}
+
+	}
+
+	private void addTwoMoreMdmLinks() {
+		createPatientAndUpdateLinks(buildFrankPatient());
+
+		// Add a possible duplicate
+		myLinkSource = new StringType(MdmLinkSourceEnum.AUTO.name());
+		Patient sourcePatient1 = createGoldenPatient();
+		myGoldenResource1Id = new StringType(sourcePatient1.getIdElement().toVersionless().getValue());
+		JpaPid sourcePatient1Pid = runInTransaction(()->myIdHelperService.getPidOrNull(RequestPartitionId.allPartitions(), sourcePatient1));
+		Patient sourcePatient2 = createGoldenPatient();
+		myGoldenResource2Id = new StringType(sourcePatient2.getIdElement().toVersionless().getValue());
+		JpaPid sourcePatient2Pid = runInTransaction(()->myIdHelperService.getPidOrNull(RequestPartitionId.allPartitions(), sourcePatient2));
+
+		MdmLink possibleDuplicateMdmLink = (MdmLink) myMdmLinkDaoSvc.newMdmLink();
+		possibleDuplicateMdmLink.setGoldenResourcePersistenceId(sourcePatient1Pid);
+		possibleDuplicateMdmLink.setSourcePersistenceId(sourcePatient2Pid);
+		possibleDuplicateMdmLink.setMatchResult(MdmMatchResultEnum.POSSIBLE_DUPLICATE).setLinkSource(MdmLinkSourceEnum.AUTO);
+		saveLink(possibleDuplicateMdmLink);
+	}
+
+
+	private void addScoresToLinksInCreationOrder(List<Double> theScores) {
+		List<MdmLink> links = myMdmLinkDao.findAll();
+		assertThat(links, hasSize(theScores.size()));
+
+		links.sort( Comparator.comparing(MdmLink::getCreated) );
+
+		for (int i = 0; i < links.size(); i++) {
+			MdmLink link = links.get(i);
+			link.setScore( theScores.get(i) );
+			myMdmLinkDao.save(link);
+		}
+	}
+
+
 	@Test
 	public void testQueryLinkWithResourceTypeNoMatch() {
-		Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null, new UnsignedIntType(0), new UnsignedIntType(10), myRequestDetails, RESOURCE_TYPE_OBSERVATION);
+		Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, null, new UnsignedIntType(0), new UnsignedIntType(10), new StringType(), myRequestDetails, RESOURCE_TYPE_OBSERVATION);
 		ourLog.debug(myFhirContext.newJsonParser().setPrettyPrint(true).encodeResourceToString(result));
 		List<Parameters.ParametersParameterComponent> list = getParametersByName(result, "link");
 		assertThat(list, hasSize(0));
@@ -110,7 +273,7 @@ public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 		int count = 2;
 		StopWatch sw = new StopWatch();
 		while (true)  {
-			Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, myLinkSource, new UnsignedIntType(offset), new UnsignedIntType(count), myRequestDetails, null);
+			Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, myLinkSource, new UnsignedIntType(offset), new UnsignedIntType(count), new StringType(), myRequestDetails, null);
 			List<Parameters.ParametersParameterComponent> parameter = result.getParameter();
 
 
@@ -156,7 +319,8 @@ public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 				null, myLinkSource,
 				new UnsignedIntType(offset),
 				new UnsignedIntType(count),
-				myRequestDetails,
+			 	new StringType(),
+			 	myRequestDetails,
 			 	null);
 		} catch (InvalidRequestException e) {
 			//Then
@@ -173,6 +337,7 @@ public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 				null, myLinkSource,
 				new UnsignedIntType(offset),
 				new UnsignedIntType(count),
+				new StringType(),
 				myRequestDetails,
 				null);
 		} catch (InvalidRequestException e) {
@@ -190,6 +355,7 @@ public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 				null, myLinkSource,
 				new UnsignedIntType(offset),
 				new UnsignedIntType(count),
+				new StringType(),
 				myRequestDetails,
 				null);
 		} catch (InvalidRequestException e) {
@@ -206,12 +372,12 @@ public class MdmProviderQueryLinkR4Test extends BaseLinkR4Test {
 		IAnyResource goldenResource = getGoldenResourceFromTargetResource(patient);
 		IIdType goldenResourceId = goldenResource.getIdElement().toVersionless();
 
-		Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, myLinkSource, new UnsignedIntType(0), new UnsignedIntType(10), myRequestDetails, null);
+		Parameters result = (Parameters) myMdmProvider.queryLinks(null, null, null, myLinkSource, new UnsignedIntType(0), new UnsignedIntType(10), new StringType(), myRequestDetails, null);
 		ourLog.debug(myFhirContext.newJsonParser().setPrettyPrint(true).encodeResourceToString(result));
 		List<Parameters.ParametersParameterComponent> list = getParametersByName(result, "link");
 		assertThat(list, hasSize(4));
 		List<Parameters.ParametersParameterComponent> part = list.get(3).getPart();
-		assertMdmLink(7, part, goldenResourceId.getValue(), patientId.getValue(), MdmMatchResultEnum.MATCH, "false", "false", "2");
+		assertMdmLink(MDM_LINK_PROPERTY_COUNT, part, goldenResourceId.getValue(), patientId.getValue(), MdmMatchResultEnum.MATCH, "false", "false", "2");
 	}
 
 	@Test

hapi-fhir-jpaserver-mdm/src/test/java/ca/uhn/fhir/jpa/mdm/svc/MdmControllerSvcImplTest.java

@@ -106,8 +106,9 @@ public class MdmControllerSvcImplTest extends BaseLinkR4Test {
 		assertEquals(MdmLinkSourceEnum.AUTO, link.getLinkSource());
 		assertLinkCount(2);
 
-		MdmQuerySearchParameters params = new MdmQuerySearchParameters(null, myPatientId.getIdElement().getValue(), null, null,
+		MdmPageRequest pageRequest = new MdmPageRequest((Integer) null, null, DEFAULT_PAGE_SIZE, MAX_PAGE_SIZE);
-			new MdmPageRequest((Integer) null, null, DEFAULT_PAGE_SIZE, MAX_PAGE_SIZE), null, null);
+		MdmQuerySearchParameters params = new MdmQuerySearchParameters(pageRequest)
+			.setSourceId(myPatientId.getIdElement().getValue());
 
 		Page<MdmLinkJson> resultPage = myMdmControllerSvc.queryLinks(params,
 			new MdmTransactionContext(MdmTransactionContext.OperationType.QUERY_LINKS),

hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/api/MdmQuerySearchParameters.java

@@ -20,16 +20,41 @@ package ca.uhn.fhir.mdm.api;
  * #L%
  */
 
+import ca.uhn.fhir.i18n.Msg;
 import ca.uhn.fhir.mdm.api.paging.MdmPageRequest;
 import ca.uhn.fhir.mdm.provider.MdmControllerUtil;
+import ca.uhn.fhir.rest.api.SortOrderEnum;
+import ca.uhn.fhir.rest.api.SortSpec;
+import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException;
 import ca.uhn.fhir.rest.server.provider.ProviderConstants;
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.hl7.fhir.instance.model.api.IIdType;
 
 import javax.annotation.Nullable;
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Set;
+
+import static org.hibernate.internal.util.StringHelper.isBlank;
 
 public class MdmQuerySearchParameters {
+
+	public static final String GOLDEN_RESOURCE_PID_NAME = "myGoldenResourcePid";
+	public static final String SOURCE_PID_NAME = "mySourcePid";
+	public static final String MATCH_RESULT_NAME = "myMatchResult";
+	public static final String LINK_SOURCE_NAME = "myLinkSource";
+	public static final String PARTITION_ID_NAME = "myPartitionId";
+	public static final String GOLDEN_RESOURCE_NAME = "myGoldenResource";
+	public static final String RESOURCE_TYPE_NAME = "myResourceType";
+	public static final String CREATED_NAME = "myCreated";
+	public static final String UPDATED_NAME = "myUpdated";
+	public static final String SCORE_NAME = "myScore";
+
+	public static final Set<String> ourValidSortParameters = Set.of(
+		GOLDEN_RESOURCE_PID_NAME, SOURCE_PID_NAME, MATCH_RESULT_NAME, LINK_SOURCE_NAME, PARTITION_ID_NAME, GOLDEN_RESOURCE_NAME,
+		RESOURCE_TYPE_NAME, CREATED_NAME, UPDATED_NAME, SCORE_NAME
+	);
+
 	private IIdType myGoldenResourceId;
 	private IIdType mySourceId;
 	private MdmMatchResultEnum myMatchResult;
@@ -37,9 +62,16 @@ public class MdmQuerySearchParameters {
 	private MdmPageRequest myPageRequest;
 	private List<Integer> myPartitionIds;
 	private String myResourceType;
+	private final List<SortSpec> mySort = new ArrayList<>();
 
+	@Deprecated(since = "2023.02.R01", forRemoval = true)
 	public MdmQuerySearchParameters() {}
 
+	public MdmQuerySearchParameters(MdmPageRequest thePageRequest) {
+		setPageRequest(thePageRequest);
+	}
+
+	@Deprecated(since = "2023.02.R01", forRemoval = true)
 	public MdmQuerySearchParameters(@Nullable String theGoldenResourceId, @Nullable String theSourceId, @Nullable String theMatchResult, @Nullable String theLinkSource, MdmPageRequest thePageRequest, @Nullable List<Integer> thePartitionIds, @Nullable String theResourceType) {
 		setGoldenResourceId(theGoldenResourceId);
 		setSourceId(theSourceId);
@@ -50,6 +82,7 @@ public class MdmQuerySearchParameters {
 		setResourceType(theResourceType);
 	}
 
+	@Deprecated(since = "2023.02.R01", forRemoval = true)
 	public MdmQuerySearchParameters(@Nullable IIdType theGoldenResourceId, @Nullable IIdType theSourceId, @Nullable MdmMatchResultEnum theMatchResult, @Nullable MdmLinkSourceEnum theLinkSource, MdmPageRequest thePageRequest, @Nullable List<Integer> thePartitionIds, @Nullable String theResourceType) {
 		setGoldenResourceId(theGoldenResourceId);
 		setSourceId(theSourceId);
@@ -64,52 +97,56 @@ public class MdmQuerySearchParameters {
 		return myGoldenResourceId;
 	}
 
-	public void setGoldenResourceId(IIdType theGoldenResourceId) {
+	public MdmQuerySearchParameters setGoldenResourceId(IIdType theGoldenResourceId) {
 		myGoldenResourceId = theGoldenResourceId;
+		return this;
 	}
 
-	public void setGoldenResourceId(String theGoldenResourceId) {
+	public MdmQuerySearchParameters setGoldenResourceId(String theGoldenResourceId) {
-		IIdType goldenResourceId = MdmControllerUtil.extractGoldenResourceIdDtOrNull(ProviderConstants.MDM_QUERY_LINKS_GOLDEN_RESOURCE_ID, theGoldenResourceId);
+		myGoldenResourceId = MdmControllerUtil.extractGoldenResourceIdDtOrNull(ProviderConstants.MDM_QUERY_LINKS_GOLDEN_RESOURCE_ID, theGoldenResourceId);
-		myGoldenResourceId = goldenResourceId;
+		return this;
 	}
 
 	public IIdType getSourceId() {
 		return mySourceId;
 	}
 
-	public void setSourceId(IIdType theSourceId) {
+	public MdmQuerySearchParameters setSourceId(IIdType theSourceId) {
 		mySourceId = theSourceId;
+		return this;
 	}
 
-	public void setSourceId(String theSourceId) {
+	public MdmQuerySearchParameters setSourceId(String theSourceId) {
-		IIdType sourceId = MdmControllerUtil.extractSourceIdDtOrNull(ProviderConstants.MDM_QUERY_LINKS_RESOURCE_ID, theSourceId);
+		mySourceId = MdmControllerUtil.extractSourceIdDtOrNull(ProviderConstants.MDM_QUERY_LINKS_RESOURCE_ID, theSourceId);
-		mySourceId = sourceId;
+		return this;
 	}
 
 	public MdmMatchResultEnum getMatchResult() {
 		return myMatchResult;
 	}
 
-	public void setMatchResult(MdmMatchResultEnum theMatchResult) {
+	public MdmQuerySearchParameters setMatchResult(MdmMatchResultEnum theMatchResult) {
 		myMatchResult = theMatchResult;
+		return this;
 	}
 
-	public void setMatchResult(String theMatchResult) {
+	public MdmQuerySearchParameters setMatchResult(String theMatchResult) {
-		MdmMatchResultEnum matchResult = MdmControllerUtil.extractMatchResultOrNull(theMatchResult);
+		myMatchResult = MdmControllerUtil.extractMatchResultOrNull(theMatchResult);
-		myMatchResult = matchResult;
+		return this;
 	}
 
 	public MdmLinkSourceEnum getLinkSource() {
 		return myLinkSource;
 	}
 
-	public void setLinkSource(MdmLinkSourceEnum theLinkSource) {
+	public MdmQuerySearchParameters setLinkSource(MdmLinkSourceEnum theLinkSource) {
 		myLinkSource = theLinkSource;
+		return this;
 	}
 
-	public void setLinkSource(String theLinkSource) {
+	public MdmQuerySearchParameters setLinkSource(String theLinkSource) {
-		MdmLinkSourceEnum linkSource = MdmControllerUtil.extractLinkSourceOrNull(theLinkSource);
+		myLinkSource = MdmControllerUtil.extractLinkSourceOrNull(theLinkSource);
-		myLinkSource = linkSource;
+		return this;
 	}
 
 	public MdmPageRequest getPageRequest() {
@@ -124,28 +161,51 @@ public class MdmQuerySearchParameters {
 		return myPartitionIds;
 	}
 
-	public void setPartitionIds(List<Integer> thePartitionIds) {
+	public MdmQuerySearchParameters setPartitionIds(List<Integer> thePartitionIds) {
 		myPartitionIds = thePartitionIds;
+		return this;
 	}
 
 	public String getResourceType() {
 		return myResourceType;
 	}
 
-	public void setResourceType(String theResourceType) {
+	public MdmQuerySearchParameters setResourceType(String theResourceType) {
 		myResourceType = theResourceType;
+		return this;
+	}
+
+	public List<SortSpec> getSort() {
+		return mySort;
+	}
+
+	public MdmQuerySearchParameters setSort(String theSortString) {
+		if (isBlank(theSortString)) {
+			return this;
+		}
+
+		for (String param : theSortString.split(",")) {
+			String p = (param.startsWith("-") ? param.substring(1) : param).trim();
+			if ( ! MdmQuerySearchParameters.ourValidSortParameters.contains(p)) {
+				throw new InvalidRequestException(Msg.code(2233) + "Unrecognized sort parameter: " + p + ". Valid parameters are: " +
+					String.join(", ", MdmQuerySearchParameters.ourValidSortParameters));
+			}
+			SortOrderEnum order = param.startsWith("-") ? SortOrderEnum.DESC : SortOrderEnum.ASC;
+			mySort.add( new SortSpec(p,  order) );
+		}
+		return this;
 	}
 
 	@Override
 	public String toString() {
 		return new ToStringBuilder(this)
-			.append("myGoldenResourceId", myGoldenResourceId)
+			.append(GOLDEN_RESOURCE_PID_NAME, myGoldenResourceId)
-			.append("mySourceId", mySourceId)
+			.append(SOURCE_PID_NAME, mySourceId)
-			.append("myMatchResult", myMatchResult)
+			.append(MATCH_RESULT_NAME, myMatchResult)
-			.append("myLinkSource", myLinkSource)
+			.append(LINK_SOURCE_NAME, myLinkSource)
-			.append("myPartitionId", myPartitionIds)
+			.append(PARTITION_ID_NAME, myPartitionIds)
+			.append(RESOURCE_TYPE_NAME, myResourceType)
 			.append("myPageRequest", myPageRequest)
-			.append("myResourceType", myResourceType)
 			.toString();
 	}
 

hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/provider/BaseMdmProvider.java

@@ -20,8 +20,8 @@ package ca.uhn.fhir.mdm.provider;
  * #L%
  */
 
-import ca.uhn.fhir.i18n.Msg;
 import ca.uhn.fhir.context.FhirContext;
+import ca.uhn.fhir.i18n.Msg;
 import ca.uhn.fhir.mdm.api.MdmLinkJson;
 import ca.uhn.fhir.mdm.api.MdmMatchResultEnum;
 import ca.uhn.fhir.mdm.api.paging.MdmPageLinkBuilder;
@@ -115,7 +115,8 @@ public abstract class BaseMdmProvider {
 		return theString.getValue();
 	}
 
-	protected IBaseParameters parametersFromMdmLinks(Page<MdmLinkJson> theMdmLinkStream, boolean includeResultAndSource, ServletRequestDetails theServletRequestDetails, MdmPageRequest thePageRequest) {
+	protected IBaseParameters parametersFromMdmLinks(Page<MdmLinkJson> theMdmLinkStream, boolean includeResultAndSource,
+																	 ServletRequestDetails theServletRequestDetails, MdmPageRequest thePageRequest) {
 		IBaseParameters retval = ParametersUtil.newInstance(myFhirContext);
 		addPagingParameters(retval, theMdmLinkStream, theServletRequestDetails, thePageRequest);
 		theMdmLinkStream.getContent().forEach(mdmLink -> {
@@ -129,6 +130,8 @@ public abstract class BaseMdmProvider {
 				ParametersUtil.addPartBoolean(myFhirContext, resultPart, "eidMatch", mdmLink.getEidMatch());
 				ParametersUtil.addPartBoolean(myFhirContext, resultPart, "hadToCreateNewResource", mdmLink.getLinkCreatedNewResource());
 				ParametersUtil.addPartDecimal(myFhirContext, resultPart, "score", mdmLink.getScore());
+				ParametersUtil.addPartDecimal(myFhirContext, resultPart, "linkCreated", (double) mdmLink.getCreated().getTime());
+				ParametersUtil.addPartDecimal(myFhirContext, resultPart, "linkUpdated", (double) mdmLink.getUpdated().getTime());
 			}
 		});
 		return retval;

hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/provider/MdmProviderDstu3Plus.java

@@ -182,25 +182,30 @@ public class MdmProviderDstu3Plus extends BaseMdmProvider {
 												 @OperationParam(name = ProviderConstants.MDM_QUERY_LINKS_LINK_SOURCE, min = 0, max = 1, typeName = "string")
 													 IPrimitiveType<String> theLinkSource,
 
-												 @Description(formalDefinition = "Results from this method are returned across multiple pages. This parameter controls the offset when fetching a page.")
+												 @Description(value = "Results from this method are returned across multiple pages. This parameter controls the offset when fetching a page.")
 												 @OperationParam(name = PARAM_OFFSET, min = 0, max = 1, typeName = "integer")
 														 IPrimitiveType<Integer> theOffset,
-												 @Description(formalDefinition = "Results from this method are returned across multiple pages. This parameter controls the size of those pages.")
+
+												 @Description(value = "Results from this method are returned across multiple pages. This parameter controls the size of those pages.")
 												 @OperationParam(name = Constants.PARAM_COUNT, min = 0, max = 1, typeName = "integer")
 														 IPrimitiveType<Integer> theCount,
+
+												 @OperationParam(name = Constants.PARAM_SORT, min = 0, max = 1, typeName = "string")
+														 IPrimitiveType<String> theSort,
+
 												 ServletRequestDetails theRequestDetails,
 												 @OperationParam(name = ProviderConstants.MDM_RESOURCE_TYPE, min = 0, max = 1, typeName = "string") IPrimitiveType<String> theResourceType
 												 ) {
 		MdmPageRequest mdmPageRequest = new MdmPageRequest(theOffset, theCount, DEFAULT_PAGE_SIZE, MAX_PAGE_SIZE);
 		MdmTransactionContext mdmContext = createMdmContext(theRequestDetails, MdmTransactionContext.OperationType.QUERY_LINKS,
 			getResourceType(ProviderConstants.MDM_QUERY_LINKS_GOLDEN_RESOURCE_ID, theGoldenResourceId, theResourceType));
-		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters();
+		MdmQuerySearchParameters mdmQuerySearchParameters = new MdmQuerySearchParameters(mdmPageRequest)
-			mdmQuerySearchParameters.setGoldenResourceId(extractStringOrNull(theGoldenResourceId));
+				.setGoldenResourceId(extractStringOrNull(theGoldenResourceId))
-			mdmQuerySearchParameters.setSourceId(extractStringOrNull(theResourceId));
+				.setSourceId(extractStringOrNull(theResourceId))
-			mdmQuerySearchParameters.setLinkSource(extractStringOrNull(theLinkSource));
+				.setLinkSource(extractStringOrNull(theLinkSource))
-			mdmQuerySearchParameters.setMatchResult(extractStringOrNull(theMatchResult));
+				.setMatchResult(extractStringOrNull(theMatchResult))
-			mdmQuerySearchParameters.setPageRequest(mdmPageRequest);
+				.setResourceType(extractStringOrNull(theResourceType))
-			mdmQuerySearchParameters.setResourceType(extractStringOrNull(theResourceType));
+				.setSort(extractStringOrNull(theSort));
 
 		Page<MdmLinkJson> mdmLinkJson = myMdmControllerSvc.queryLinks(mdmQuerySearchParameters, mdmContext, theRequestDetails);
 		return parametersFromMdmLinks(mdmLinkJson, true, theRequestDetails, mdmPageRequest);

hapi-fhir-server-mdm/src/test/java/ca/uhn/fhir/mdm/api/MdmQuerySearchParametersTest.java

@@ -20,13 +20,12 @@ class MdmQuerySearchParametersTest {
 
 	@Test
 	public void testMdmQuerySearchParameters() {
-		MdmQuerySearchParameters params = new MdmQuerySearchParameters();
+		MdmQuerySearchParameters params = new MdmQuerySearchParameters(PAGE_REQUEST);
 		params.setGoldenResourceId(GOLDEN_RESOURCE_ID);
 		params.setSourceId(SOURCE_ID);
 		params.setMatchResult(MATCH_RESULT);
 		params.setLinkSource(LINK_SOURCE);
 		params.setPartitionIds(PARTITION_ID);
-		params.setPageRequest(PAGE_REQUEST);
 		params.setResourceType(RESOURCE_TYPE);
 		assertEquals(GOLDEN_RESOURCE_ID, params.getGoldenResourceId().getValueAsString());
 		assertEquals(SOURCE_ID, params.getSourceId().getValueAsString());