added header check

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

@@ -586,7 +586,7 @@ public abstract class BaseHapiFhirResourceDao<T extends IBaseResource> extends B
 			throw new MethodNotAllowedException("_expunge is not enabled on this server: " + getConfig().cannotDeleteExpungeReason());
 		}
 
-		if (theUrl.contains("_cascade")) {
+		if (theUrl.contains(JpaConstants.PARAM_DELETE_CASACADE) || theRequest.getHeader("X-Cascade").equals("delete")) {
 			throw new NotImplementedOperationException("_expunge cannot be used with _cascade");
 		}
 

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/expunge/DeleteExpungeDaoTest.java

@@ -67,10 +67,11 @@ class DeleteExpungeDaoTest extends BaseJpaR4Test {
 
 		// Try to delete _cascade and _expunge on the organization
 		BaseServerResponseException e = assertThrows(BaseServerResponseException.class, () -> {myOrganizationDao
-			.deleteByUrl("Organization?" + "_cascade=true&" + JpaConstants.PARAM_DELETE_EXPUNGE + "=true", mySrd);});
+			.deleteByUrl("Organization?" + "_cascade=delete&" + JpaConstants.PARAM_DELETE_EXPUNGE + "=true", mySrd);});
 
 		// Get not implemented HTTP 501 error
 		assertEquals(Constants.STATUS_HTTP_501_NOT_IMPLEMENTED, e.getStatusCode());
+		assertEquals("_expunge cannot be used with _cascade", e.getMessage());
 	}
 
 	@Test

hapi-fhir-jpaserver-model/src/main/java/ca/uhn/fhir/jpa/model/util/JpaConstants.java

@@ -200,6 +200,12 @@ public class JpaConstants {
 
 	public static final String PARAM_DELETE_EXPUNGE = "_expunge";
 
+	/**
+	 * Parameter for delete to indicate the resource should be cascading delete
+	 */
+
+	public static final String PARAM_DELETE_CASACADE = "_cascade";
+
 	/**
 	 * URL for extension on a SearchParameter indicating that text values should not be indexed
 	 */