fixed mdmjsonlink serialization issues (#5987)

* fixed mdmjsonlink serialization issues

* spotless

* test fixing

* spotless

* review fixes

* spotless

* fixing

* spotless

---------

Co-authored-by: leif stawnyczy <leifstawnyczy@leifs-mbp.home>

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_4_0/5986-fixing-bug-with-deserializing-mdmlink-json.yaml

@@ -0,0 +1,8 @@
+---
+type: fix
+issue: 5985
+title: "Fixed an issue where MDM json links were unserializable
+        due to using the IResourcePersistenceId objects.
+        This has been fixed, and IResourcePersistenceId objects
+        will not be serialized or returned to users.
+"

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/index/IdHelperService.java

@@ -125,7 +125,7 @@ public class IdHelperService implements IIdHelperService<JpaPid> {
 	private boolean myDontCheckActiveTransactionForUnitTest;
 
 	@VisibleForTesting
-	void setDontCheckActiveTransactionForUnitTest(boolean theDontCheckActiveTransactionForUnitTest) {
+	protected void setDontCheckActiveTransactionForUnitTest(boolean theDontCheckActiveTransactionForUnitTest) {
 		myDontCheckActiveTransactionForUnitTest = theDontCheckActiveTransactionForUnitTest;
 	}
 

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/index/IdHelperServiceTest.java

@@ -20,11 +20,20 @@ import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentMatchers;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.Spy;
 import org.mockito.junit.jupiter.MockitoExtension;
 
 import java.util.List;
 import java.util.Map;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.lenient;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNull;
@@ -37,7 +46,7 @@ import static org.mockito.Mockito.when;
 public class IdHelperServiceTest {
 
     @InjectMocks
-    private final IdHelperService subject = new IdHelperService();
+    private final IdHelperService myHelperSvc = new IdHelperService();
 
     @Mock
     protected IResourceTableDao myResourceTableDao;
@@ -45,8 +54,8 @@ public class IdHelperServiceTest {
     @Mock
     private JpaStorageSettings myStorageSettings;
 
-    @Mock
+    @Spy
-    private FhirContext myFhirCtx;
+    private FhirContext myFhirCtx = FhirContext.forR4Cached();
 
     @Mock
     private MemoryCacheService myMemoryCacheService;
@@ -59,10 +68,11 @@ public class IdHelperServiceTest {
 
     @BeforeEach
     void setUp() {
-        subject.setDontCheckActiveTransactionForUnitTest(true);
+        myHelperSvc.setDontCheckActiveTransactionForUnitTest(true);
 
-		when(myStorageSettings.isDeleteEnabled()).thenReturn(true);
+		// lenient because some tests require this setup, and others do not
-		when(myStorageSettings.getResourceClientIdStrategy()).thenReturn(JpaStorageSettings.ClientIdStrategyEnum.ANY);
+		lenient().doReturn(true).when(myStorageSettings).isDeleteEnabled();
+		lenient().doReturn(JpaStorageSettings.ClientIdStrategyEnum.ANY).when(myStorageSettings).getResourceClientIdStrategy();
     }
 
     @Test
@@ -81,7 +91,7 @@ public class IdHelperServiceTest {
         // configure mock behaviour
 		when(myStorageSettings.isDeleteEnabled()).thenReturn(true);
 
-		final ResourceNotFoundException resourceNotFoundException = assertThrows(ResourceNotFoundException.class, () -> subject.resolveResourcePersistentIds(requestPartitionId, resourceType, ids, theExcludeDeleted));
+		final ResourceNotFoundException resourceNotFoundException = assertThrows(ResourceNotFoundException.class, () -> myHelperSvc.resolveResourcePersistentIds(requestPartitionId, resourceType, ids, theExcludeDeleted));
 		assertEquals("HAPI-2001: Resource Patient/123 is not known", resourceNotFoundException.getMessage());
     }
 
@@ -102,13 +112,14 @@ public class IdHelperServiceTest {
         // configure mock behaviour
         when(myStorageSettings.isDeleteEnabled()).thenReturn(false);
 
-		Map<String, JpaPid> actualIds = subject.resolveResourcePersistentIds(requestPartitionId, resourceType, ids, theExcludeDeleted);
+		Map<String, JpaPid> actualIds = myHelperSvc.resolveResourcePersistentIds(requestPartitionId, resourceType, ids, theExcludeDeleted);
 
 		//verifyResult
 		assertFalse(actualIds.isEmpty());
 		assertNull(actualIds.get(ids.get(0)));
     }
 
+
     private Root<ResourceTable> getMockedFrom() {
         @SuppressWarnings("unchecked")
         Path<Object> path = mock(Path.class);

hapi-fhir-jpaserver-mdm/src/main/java/ca/uhn/fhir/jpa/mdm/config/MdmSurvivorshipConfig.java

@@ -22,6 +22,7 @@ package ca.uhn.fhir.jpa.mdm.config;
 import ca.uhn.fhir.context.FhirContext;
 import ca.uhn.fhir.jpa.api.dao.DaoRegistry;
 import ca.uhn.fhir.jpa.api.svc.IIdHelperService;
+import ca.uhn.fhir.jpa.dao.tx.HapiTransactionService;
 import ca.uhn.fhir.mdm.api.IMdmLinkQuerySvc;
 import ca.uhn.fhir.mdm.api.IMdmSettings;
 import ca.uhn.fhir.mdm.api.IMdmSurvivorshipService;
@@ -57,10 +58,18 @@ public class MdmSurvivorshipConfig {
 	@Autowired
 	private IIdHelperService<?> myIIdHelperService;
 
+	@Autowired
+	private HapiTransactionService myTransactionService;
+
 	@Bean
 	public IMdmSurvivorshipService mdmSurvivorshipService() {
 		return new MdmSurvivorshipSvcImpl(
-				myFhirContext, goldenResourceHelper(), myDaoRegistry, myMdmLinkQuerySvc, myIIdHelperService);
+				myFhirContext,
+				goldenResourceHelper(),
+				myDaoRegistry,
+				myMdmLinkQuerySvc,
+				myIIdHelperService,
+				myTransactionService);
 	}
 
 	@Bean

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

@@ -44,13 +44,17 @@ public class MdmModelConverterSvcImpl implements IMdmModelConverterSvc {
 				.toVersionless()
 				.getValue();
 		retVal.setSourceId(sourceId);
+		if (theLink.getSourcePersistenceId() != null) {
 			retVal.setSourcePid(theLink.getSourcePersistenceId());
+		}
 		String goldenResourceId = myIdHelperService
 				.resourceIdFromPidOrThrowException(theLink.getGoldenResourcePersistenceId(), theLink.getMdmSourceType())
 				.toVersionless()
 				.getValue();
 		retVal.setGoldenResourceId(goldenResourceId);
+		if (theLink.getGoldenResourcePersistenceId() != null) {
 			retVal.setGoldenPid(theLink.getGoldenResourcePersistenceId());
+		}
 		retVal.setCreated(theLink.getCreated());
 		retVal.setEidMatch(theLink.getEidMatch());
 		retVal.setLinkSource(theLink.getLinkSource());

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

@@ -50,8 +50,15 @@ public class MdmModelConverterSvcImplTest extends BaseMdmR4Test {
 
 		ourLog.info("actualMdmLinkJson: {}", actualMdmLinkJson);
 
-		MdmLinkJson exepctedMdmLinkJson = getExepctedMdmLinkJson(mdmLink.getGoldenResourcePersistenceId().getId(), mdmLink.getSourcePersistenceId().getId(), MdmMatchResultEnum.MATCH, MdmLinkSourceEnum.MANUAL, version, createTime, updateTime, isLinkCreatedResource, scoreRounded);
+		MdmLinkJson expectedMdmLinkJson = getExepctedMdmLinkJson(mdmLink.getGoldenResourcePersistenceId().getId(), mdmLink.getSourcePersistenceId().getId(), MdmMatchResultEnum.MATCH, MdmLinkSourceEnum.MANUAL, version, createTime, updateTime, isLinkCreatedResource, scoreRounded);
-		assertEquals(exepctedMdmLinkJson, actualMdmLinkJson);
+		assertEquals(expectedMdmLinkJson.getSourceId(), actualMdmLinkJson.getSourceId());
+		assertEquals(expectedMdmLinkJson.getGoldenResourceId(), actualMdmLinkJson.getGoldenResourceId());
+		assertEquals(expectedMdmLinkJson.getGoldenPid().getId(), actualMdmLinkJson.getGoldenPid().getId());
+		assertEquals(expectedMdmLinkJson.getSourcePid().getId(), actualMdmLinkJson.getSourcePid().getId());
+		assertEquals(expectedMdmLinkJson.getVector(), actualMdmLinkJson.getVector());
+		assertEquals(expectedMdmLinkJson.getScore(), actualMdmLinkJson.getScore());
+		assertEquals(expectedMdmLinkJson.getMatchResult(), actualMdmLinkJson.getMatchResult());
+		assertEquals(expectedMdmLinkJson.getLinkSource(), actualMdmLinkJson.getLinkSource());
 	}
 
 	@Test

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

@@ -1,11 +1,12 @@
 package ca.uhn.fhir.jpa.mdm.svc;
 
 import ca.uhn.fhir.context.FhirContext;
+import ca.uhn.fhir.interceptor.model.RequestPartitionId;
 import ca.uhn.fhir.jpa.api.dao.DaoRegistry;
 import ca.uhn.fhir.jpa.api.dao.IFhirResourceDao;
-import ca.uhn.fhir.jpa.api.svc.IIdHelperService;
 import ca.uhn.fhir.jpa.dao.index.IdHelperService;
-import ca.uhn.fhir.jpa.entity.MdmLink;
+import ca.uhn.fhir.jpa.dao.tx.HapiTransactionService;
+import ca.uhn.fhir.jpa.dao.tx.IHapiTransactionService;
 import ca.uhn.fhir.jpa.model.dao.JpaPid;
 import ca.uhn.fhir.mdm.api.IMdmLinkQuerySvc;
 import ca.uhn.fhir.mdm.api.IMdmSettings;
@@ -21,6 +22,7 @@ import ca.uhn.fhir.mdm.util.GoldenResourceHelper;
 import ca.uhn.fhir.mdm.util.MdmPartitionHelper;
 import ca.uhn.fhir.mdm.util.MdmResourceUtil;
 import ca.uhn.fhir.rest.api.server.RequestDetails;
+import ca.uhn.fhir.rest.api.server.storage.IResourcePersistentId;
 import org.hl7.fhir.instance.model.api.IBaseResource;
 import org.hl7.fhir.r4.model.Patient;
 import org.junit.jupiter.api.BeforeEach;
@@ -31,20 +33,23 @@ import org.mockito.Mock;
 import org.mockito.Spy;
 import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.domain.Page;
+import org.springframework.data.domain.PageImpl;
 
-import java.time.Instant;
-import java.time.temporal.ChronoUnit;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.Date;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
@@ -69,12 +74,15 @@ public class MdmSurvivorshipSvcImplTest {
 	@Mock
 	private MdmPartitionHelper myMdmPartitionHelper;
 
-	@Spy
+	@Mock
-	private IIdHelperService<?> myIIdHelperService = new IdHelperService();
+	private IdHelperService myIIdHelperService;
 
 	@Mock
 	private IMdmLinkQuerySvc myMdmLinkQuerySvc;
 
+	@Mock
+	private HapiTransactionService myTransactionService;
+
 	private MdmSurvivorshipSvcImpl mySvc;
 
 	@BeforeEach
@@ -91,7 +99,8 @@ public class MdmSurvivorshipSvcImplTest {
 			myGoldenResourceHelper,
 			myDaoRegistry,
 			myMdmLinkQuerySvc,
-			myIIdHelperService
+			myIIdHelperService,
+			myTransactionService
 		);
 	}
 
@@ -115,7 +124,7 @@ public class MdmSurvivorshipSvcImplTest {
 
 		List<IBaseResource> resources = new ArrayList<>();
 		List<MdmLinkJson> links = new ArrayList<>();
-
+		Map<String, IResourcePersistentId> sourceIdToPid = new HashMap<>();
 		for (int i = 0; i < 10; i++) {
 			// we want our resources to be slightly different
 			Patient patient = new Patient();
@@ -137,24 +146,34 @@ public class MdmSurvivorshipSvcImplTest {
 			);
 			link.setSourcePid(JpaPid.fromId((long)i));
 			link.setGoldenPid(JpaPid.fromId((long)goldenId));
+			link.setSourceId(patient.getId());
+			link.setGoldenResourceId(goldenPatient.getId());
 			links.add(link);
+			sourceIdToPid.put(patient.getId(), link.getSourcePid());
 		}
 
 		IFhirResourceDao resourceDao = mock(IFhirResourceDao.class);
 
 		// when
+		IHapiTransactionService.IExecutionBuilder executionBuilder = mock(IHapiTransactionService.IExecutionBuilder.class);
+		when(myTransactionService.withRequest(any())).thenReturn(executionBuilder);
+		doAnswer(a -> {
+			Runnable callback = a.getArgument(0);
+			callback.run();
+			return 0;
+		}).when(executionBuilder).execute(any(Runnable.class));
 		when(myDaoRegistry.getResourceDao(eq("Patient")))
 			.thenReturn(resourceDao);
 		AtomicInteger counter = new AtomicInteger();
 		when(resourceDao.readByPid(any()))
 			.thenAnswer(params -> resources.get(counter.getAndIncrement()));
-		Page<MdmLinkJson> linkPage = mock(Page.class);
+		Page<MdmLinkJson> linkPage = new PageImpl<>(links);
 		when(myMdmLinkQuerySvc.queryLinks(any(), any()))
 			.thenReturn(linkPage);
-		when(linkPage.get())
-			.thenReturn(links.stream());
 		when(myMdmSettings.getMdmRules())
 			.thenReturn(new MdmRulesJson());
+		doReturn(sourceIdToPid).when(myIIdHelperService)
+			.resolveResourcePersistentIds(any(RequestPartitionId.class), anyString(), any(List.class));
 		// we will return a non-empty list to reduce mocking
 		when(myEIDHelper.getExternalEid(any()))
 			.thenReturn(Collections.singletonList(new CanonicalEID("example", "value", "use")));
@@ -178,19 +197,6 @@ public class MdmSurvivorshipSvcImplTest {
 			.update(eq(goldenPatientRebuilt), any(RequestDetails.class));
 	}
 
-	private MdmLink createLinkWithoutUpdateDate(Patient theSource, Patient theGoldenResource) {
-		MdmLink link = new MdmLink();
-		link.setCreated(Date.from(
-			Instant.now().minus(2, ChronoUnit.DAYS)
-		));
-		link.setLinkSource(MdmLinkSourceEnum.AUTO);
-		link.setMatchResult(MdmMatchResultEnum.MATCH);
-		link.setSourcePersistenceId(JpaPid.fromId(theSource.getIdElement().getIdPartAsLong()));
-		link.setGoldenResourcePersistenceId(JpaPid.fromId(theGoldenResource.getIdElement().getIdPartAsLong()));
-
-		return link;
-	}
-
 	private MdmTransactionContext createTransactionContext() {
 		MdmTransactionContext context = new MdmTransactionContext();
 		context.setRestOperation(MdmTransactionContext.OperationType.UPDATE_LINK);

hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/model/mdmevents/MdmLinkJson.java

@@ -23,6 +23,7 @@ import ca.uhn.fhir.mdm.api.MdmLinkSourceEnum;
 import ca.uhn.fhir.mdm.api.MdmMatchResultEnum;
 import ca.uhn.fhir.model.api.IModelJson;
 import ca.uhn.fhir.rest.api.server.storage.IResourcePersistentId;
+import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 import java.util.Date;
@@ -45,13 +46,13 @@ public class MdmLinkJson implements IModelJson {
 	/**
 	 * Golden resource PID
 	 */
-	@JsonProperty("goldenPid")
+	@JsonIgnore
 	private IResourcePersistentId<?> myGoldenPid;
 
 	/**
 	 * Source PID
 	 */
-	@JsonProperty("sourcePid")
+	@JsonIgnore
 	private IResourcePersistentId<?> mySourcePid;
 
 	/**

hapi-fhir-server-mdm/src/main/java/ca/uhn/fhir/mdm/svc/MdmSurvivorshipSvcImpl.java

@@ -24,6 +24,7 @@ import ca.uhn.fhir.interceptor.model.RequestPartitionId;
 import ca.uhn.fhir.jpa.api.dao.DaoRegistry;
 import ca.uhn.fhir.jpa.api.dao.IFhirResourceDao;
 import ca.uhn.fhir.jpa.api.svc.IIdHelperService;
+import ca.uhn.fhir.jpa.dao.tx.HapiTransactionService;
 import ca.uhn.fhir.mdm.api.IMdmLinkQuerySvc;
 import ca.uhn.fhir.mdm.api.IMdmSurvivorshipService;
 import ca.uhn.fhir.mdm.api.MdmMatchResultEnum;
@@ -36,12 +37,15 @@ import ca.uhn.fhir.rest.api.Constants;
 import ca.uhn.fhir.rest.api.server.SystemRequestDetails;
 import ca.uhn.fhir.rest.api.server.storage.IResourcePersistentId;
 import ca.uhn.fhir.util.TerserUtil;
-import org.apache.commons.lang3.StringUtils;
 import org.hl7.fhir.instance.model.api.IAnyResource;
 import org.hl7.fhir.instance.model.api.IBase;
 import org.hl7.fhir.instance.model.api.IBaseResource;
 import org.springframework.data.domain.Page;
 
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
@@ -58,17 +62,21 @@ public class MdmSurvivorshipSvcImpl implements IMdmSurvivorshipService {
 
 	private final IIdHelperService<?> myIIdHelperService;
 
+	private final HapiTransactionService myTransactionService;
+
 	public MdmSurvivorshipSvcImpl(
 			FhirContext theFhirContext,
 			GoldenResourceHelper theResourceHelper,
 			DaoRegistry theDaoRegistry,
 			IMdmLinkQuerySvc theLinkQuerySvc,
-			IIdHelperService<?> theIIdHelperService) {
+			IIdHelperService<?> theIIdHelperService,
+			HapiTransactionService theHapiTransactionService) {
 		myFhirContext = theFhirContext;
 		myGoldenResourceHelper = theResourceHelper;
 		myDaoRegistry = theDaoRegistry;
 		myMdmLinkQuerySvc = theLinkQuerySvc;
 		myIIdHelperService = theIIdHelperService;
+		myTransactionService = theHapiTransactionService;
 	}
 
 	// this logic is custom in smile vs hapi
@@ -132,6 +140,7 @@ public class MdmSurvivorshipSvcImpl implements IMdmSurvivorshipService {
 		return (T) toSave;
 	}
 
+	@SuppressWarnings("rawtypes")
 	private Stream<IBaseResource> getMatchedSourceIdsByLinkUpdateDate(
 			IBaseResource theGoldenResource, MdmTransactionContext theMdmTransactionContext) {
 		String resourceType = theGoldenResource.fhirType();
@@ -143,18 +152,27 @@ public class MdmSurvivorshipSvcImpl implements IMdmSurvivorshipService {
 		searchParameters.setMatchResult(MdmMatchResultEnum.MATCH);
 		Page<MdmLinkJson> linksQuery = myMdmLinkQuerySvc.queryLinks(searchParameters, theMdmTransactionContext);
 
-		return linksQuery.get().map(link -> {
+		// we want it ordered
-			IResourcePersistentId<?> pid = link.getSourcePid();
+		List<String> sourceIds = new ArrayList<>();
-			return dao.readByPid(pid);
+		linksQuery.forEach(link -> {
+			sourceIds.add(link.getSourceId());
+		});
+		Map<String, IResourcePersistentId> sourceIdToPid = new HashMap<>();
+		if (!sourceIds.isEmpty()) {
+			// we cannot call resolveResourcePersistentIds if there are no ids to call it with
+			myTransactionService
+					.withRequest(new SystemRequestDetails().setRequestPartitionId(RequestPartitionId.allPartitions()))
+					.execute(() -> {
+						Map<String, ? extends IResourcePersistentId> ids =
+								myIIdHelperService.resolveResourcePersistentIds(
+										RequestPartitionId.allPartitions(), resourceType, sourceIds);
+						sourceIdToPid.putAll(ids);
 					});
 		}
 
-	private IResourcePersistentId<?> getResourcePID(String theId, String theResourceType) {
+		return sourceIds.stream().map(id -> {
-		return myIIdHelperService.newPidFromStringIdAndResourceName(theId, theResourceType);
+			IResourcePersistentId<?> pid = sourceIdToPid.get(id);
-	}
+			return dao.readByPid(pid);
-
+		});
-	private boolean isNumericOrUuid(String theLongCandidate) {
-		return StringUtils.isNumeric(theLongCandidate)
-				|| IS_UUID.matcher(theLongCandidate).matches();
 	}
 }

hapi-fhir-server-mdm/src/test/java/ca/uhn/fhir/mdm/model/mdmevents/MdmLinkJsonTest.java

@@ -0,0 +1,70 @@
+package ca.uhn.fhir.mdm.model.mdmevents;
+
+import ca.uhn.fhir.mdm.api.MdmLinkSourceEnum;
+import ca.uhn.fhir.mdm.api.MdmMatchResultEnum;
+import ca.uhn.fhir.rest.api.server.storage.BaseResourcePersistentId;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.hl7.fhir.r4.model.IdType;
+import org.junit.jupiter.api.Test;
+
+import java.util.Date;
+
+import static org.apache.commons.lang3.StringUtils.isBlank;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+public class MdmLinkJsonTest {
+
+	private static class TestPID<T> extends BaseResourcePersistentId<T> {
+
+		private final T myId;
+
+		protected TestPID(String theResourceType, T theId) {
+			super(theResourceType);
+			myId = theId;
+		}
+
+		@Override
+		public T getId() {
+			return myId;
+		}
+	}
+
+	private final ObjectMapper myObjectMapper = new ObjectMapper();
+
+	@Test
+	public void serializeDeserialize_longId_works() throws JsonProcessingException {
+		// setup
+		MdmLinkJson json = createLinkJson();
+		TestPID<Long> golden = new TestPID<>("Patient", 1L);
+		golden.setAssociatedResourceId(new IdType("Patient/1"));
+		golden.setVersion(1L);
+		TestPID<Long> source = new TestPID<>("Patient", 2L);
+		source.setAssociatedResourceId(new IdType("Patient/2"));
+		source.setVersion(1L);
+		json.setGoldenPid(golden);
+		json.setSourcePid(source);
+
+		// test
+		String strVal = myObjectMapper.writeValueAsString(json);
+		assertFalse(isBlank(strVal));
+
+		MdmLinkJson deserialized = myObjectMapper.readValue(strVal, MdmLinkJson.class);
+		assertNotNull(deserialized);
+		assertNull(deserialized.getSourcePid());
+		assertNull(deserialized.getGoldenPid());
+	}
+
+	private MdmLinkJson createLinkJson() {
+		MdmLinkJson json = new MdmLinkJson();
+		json.setGoldenResourceId("Patient/1");
+		json.setSourceId("Patient/2");
+		json.setMatchResult(MdmMatchResultEnum.MATCH);
+		json.setLinkSource(MdmLinkSourceEnum.MANUAL);
+		json.setCreated(new Date());
+		json.setUpdated(new Date());
+		return json;
+	}
+}

hapi-fhir-server/src/main/java/ca/uhn/fhir/rest/api/server/storage/IResourcePersistentId.java

@@ -22,6 +22,7 @@ package ca.uhn.fhir.rest.api.server.storage;
 import org.hl7.fhir.instance.model.api.IIdType;
 
 public interface IResourcePersistentId<T> {
+
 	IResourcePersistentId NOT_FOUND = new NotFoundPid();
 
 	IIdType getAssociatedResourceId();
@@ -31,6 +32,7 @@ public interface IResourcePersistentId<T> {
 	T getId();
 
 	Long getVersion();
+
 	/**
 	 * @param theVersion This should only be populated if a specific version is needed. If you want the current version,
 	 *                   leave this as <code>null</code>