6182 introduce a new pointcut to allow customization before sending message to the broker on mdm submit (#6183)

* add a new pointcut for changing message before submitting it to message broker

* failing test

* fix test by invoking hook when hook is registered

* spotless

* update docs

* changelog

* review changes

* spotless

hapi-fhir-base/src/main/java/ca/uhn/fhir/interceptor/api/Pointcut.java

@@ -2515,6 +2515,22 @@ public enum Pointcut implements IPointcut {
 	MDM_SUBMIT(
 			void.class, "ca.uhn.fhir.rest.api.server.RequestDetails", "ca.uhn.fhir.mdm.model.mdmevents.MdmSubmitEvent"),
 
+	/**
+	 * <b>MDM_SUBMIT_PRE_MESSAGE_DELIVERY Hook:</b>
+	 * Invoked immediately before the delivery of a MESSAGE to the broker.
+	 * <p>
+	 * Hooks can make changes to the delivery payload.
+	 * Furthermore, modification can be made to the outgoing message,
+	 * for example adding headers or changing message key,
+	 * which will be used for the subsequent processing.
+	 * </p>
+	 * Hooks should accept the following parameters:
+	 * <ul>
+	 * <li>ca.uhn.fhir.jpa.subscription.model.ResourceModifiedJsonMessage</li>
+	 * </ul>
+	 */
+	MDM_SUBMIT_PRE_MESSAGE_DELIVERY(void.class, "ca.uhn.fhir.jpa.subscription.model.ResourceModifiedJsonMessage"),
+
 	/**
 	 * <b>JPA Hook:</b>
 	 * This hook is invoked when a cross-partition reference is about to be

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_6_0/6182-new-pointcut-for-mdm-submit.yml

@@ -0,0 +1,4 @@
+---
+type: add
+issue: 6182
+title: "A new Pointcut called `MDM_SUBMIT_PRE_MESSAGE_DELIVERY` has been added. If you wish to customize the `ResourceModifiedJsonMessage` sent to the broker, you can do so by implementing this Pointcut, and returning `ResourceModifiedJsonMessage`."

hapi-fhir-jpaserver-mdm/src/test/java/ca/uhn/fhir/jpa/mdm/provider/MdmProviderBatchR4Test.java

@@ -1,8 +1,10 @@
 package ca.uhn.fhir.jpa.mdm.provider;
 
 import ca.uhn.fhir.i18n.Msg;
+import ca.uhn.fhir.interceptor.api.Hook;
 import ca.uhn.fhir.interceptor.api.IInterceptorService;
 import ca.uhn.fhir.interceptor.api.Pointcut;
+import ca.uhn.fhir.jpa.subscription.model.ResourceModifiedJsonMessage;
 import ca.uhn.fhir.mdm.log.Logs;
 import ca.uhn.fhir.mdm.rules.config.MdmSettings;
 import ca.uhn.fhir.rest.server.exceptions.InternalErrorException;
@@ -30,6 +32,7 @@ import org.junit.jupiter.params.provider.MethodSource;
 import org.springframework.beans.factory.annotation.Autowired;
 
 import java.io.IOException;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Stream;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -245,16 +248,24 @@ public class MdmProviderBatchR4Test extends BaseLinkR4Test {
 		Patient janePatient = createPatientAndUpdateLinks(buildJanePatient());
 		Patient janePatient2 = createPatientAndUpdateLinks(buildJanePatient());
 		assertLinkCount(5);
-
+		final AtomicBoolean mdmSubmitBeforeMessageDeliveryHookCalled = new AtomicBoolean();
+		final Object interceptor =  new Object() {
+			@Hook(Pointcut.MDM_SUBMIT_PRE_MESSAGE_DELIVERY)
+			void hookMethod(ResourceModifiedJsonMessage theResourceModifiedJsonMessage) {
+				mdmSubmitBeforeMessageDeliveryHookCalled.set(true);
+			}
+		};
+		myInterceptorService.registerInterceptor(interceptor);
 		// When
 		clearMdmLinks();
 		afterMdmLatch.runWithExpectedCount(3, () -> {
 			myMdmProvider.mdmBatchPatientType(null , null, theSyncOrAsyncRequest);
 		});
-
 		// Then
+		assertThat(mdmSubmitBeforeMessageDeliveryHookCalled).isTrue();
 		updatePatientAndUpdateLinks(janePatient);
 		updatePatientAndUpdateLinks(janePatient2);
 		assertLinkCount(3);
+		myInterceptorService.unregisterInterceptor(interceptor);
 	}
 }

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

@@ -20,6 +20,9 @@
 package ca.uhn.fhir.mdm.svc;
 
 import ca.uhn.fhir.context.FhirContext;
+import ca.uhn.fhir.interceptor.api.HookParams;
+import ca.uhn.fhir.interceptor.api.IInterceptorBroadcaster;
+import ca.uhn.fhir.interceptor.api.Pointcut;
 import ca.uhn.fhir.interceptor.model.RequestPartitionId;
 import ca.uhn.fhir.jpa.subscription.channel.api.ChannelProducerSettings;
 import ca.uhn.fhir.jpa.subscription.channel.api.IChannelFactory;
@@ -44,9 +47,12 @@ public class MdmChannelSubmitterSvcImpl implements IMdmChannelSubmitterSvc {
 
 	private MessageChannel myMdmChannelProducer;
 
-	private FhirContext myFhirContext;
+	private final FhirContext myFhirContext;
 
-	private IChannelFactory myChannelFactory;
+	private final IChannelFactory myChannelFactory;
+
+	@Autowired
+	private IInterceptorBroadcaster myInterceptorBroadcaster;
 
 	@Override
 	public void submitResourceToMdmChannel(IBaseResource theResource) {
@@ -59,6 +65,11 @@ public class MdmChannelSubmitterSvcImpl implements IMdmChannelSubmitterSvc {
 				(RequestPartitionId) theResource.getUserData(Constants.RESOURCE_PARTITION_ID));
 		resourceModifiedMessage.setOperationType(ResourceModifiedMessage.OperationTypeEnum.MANUALLY_TRIGGERED);
 		resourceModifiedJsonMessage.setPayload(resourceModifiedMessage);
+		if (myInterceptorBroadcaster.hasHooks(Pointcut.MDM_SUBMIT_PRE_MESSAGE_DELIVERY)) {
+			final HookParams params =
+					new HookParams().add(ResourceModifiedJsonMessage.class, resourceModifiedJsonMessage);
+			myInterceptorBroadcaster.callHooks(Pointcut.MDM_SUBMIT_PRE_MESSAGE_DELIVERY, params);
+		}
 		boolean success = getMdmChannelProducer().send(resourceModifiedJsonMessage);
 		if (!success) {
 			ourLog.error("Failed to submit {} to MDM Channel.", resourceModifiedMessage.getPayloadId());