3322 graph ql searches cannot be executed when number of matching results exceeds default page size (#3323)

* fix NPE

* check if size is null

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/5_7_0/3322-GraphQL-searches-cannot-be-executed-when-number-of-matching-results-exceeds-default-page-size.yaml

@@ -0,0 +1,5 @@
+---
+type: fix
+issue: 3322
+jira: SMILE-3424
+title: "GraphQL searches cannot be executed when number of matching results exceeds default page size. This has been corrected."

hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/search/SearchCoordinatorSvcImpl.java

@@ -562,7 +562,7 @@ public class SearchCoordinatorSvcImpl implements ISearchCoordinatorSvc {
 					bundleProvider.setSize(null);
 				}
 			}
-
+			bundleProvider.setPreferredPageSize(theParams.getCount());
 			return bundleProvider;
 		});
 	}

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/graphql/DaoRegistryGraphQLStorageServicesTest.java

@@ -1,10 +1,11 @@
 package ca.uhn.fhir.jpa.graphql;
 
+import ca.uhn.fhir.context.FhirContext;
 import ca.uhn.fhir.jpa.api.config.DaoConfig;
 import ca.uhn.fhir.jpa.config.TestR4Config;
 import ca.uhn.fhir.jpa.dao.r4.BaseJpaR4Test;
+import ca.uhn.fhir.rest.server.RestfulServer;
 import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException;
-import ca.uhn.fhir.rest.server.exceptions.UnprocessableEntityException;
 import org.hl7.fhir.instance.model.api.IBaseResource;
 import org.hl7.fhir.r4.model.Appointment;
 import org.hl7.fhir.r4.model.CodeableConcept;
@@ -25,18 +26,23 @@ import org.springframework.test.context.junit.jupiter.SpringExtension;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.HashMap;
 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.assertTrue;
 import static org.junit.jupiter.api.Assertions.fail;
 
+import static ca.uhn.fhir.rest.api.Constants.PARAM_COUNT;
+import static org.mockito.Mockito.when;
 
 @ContextConfiguration(classes = {TestR4Config.class})
 @ExtendWith(SpringExtension.class)
 @DirtiesContext
 public class DaoRegistryGraphQLStorageServicesTest extends BaseJpaR4Test {
+	private static final FhirContext ourCtx = FhirContext.forR4Cached();
 
 	@Autowired
 	private IGraphQLStorageServices mySvc;
@@ -134,4 +140,41 @@ public class DaoRegistryGraphQLStorageServicesTest extends BaseJpaR4Test {
 		List<String> expectedId = Arrays.asList("hapi-123", "hapi-124");
 		assertTrue(result.stream().allMatch((it) -> expectedId.contains(it.getIdElement().getIdPart())));
 	}
+
+	@Test
+	public void testListResourceGraphqlWithPageSizeSmallerThanResultSize() {
+		for (int i = 0; i < 10; i++) {
+			createSomePatientWithId("hapi-" + i);
+		}
+
+		Argument argument = new Argument();
+		argument.setName("_id");
+		for (int i = 0; i < 10; i++) {
+			argument.addValue(new StringValue("hapi-" + i));
+		}
+
+		//fisrt page
+		List<IBaseResource> result = new ArrayList<>();
+		when(mySrd.getServer().getDefaultPageSize()).thenReturn(5);
+		mySvc.listResources(mySrd, "Patient", Collections.singletonList(argument), result);
+
+		assertFalse(result.isEmpty());
+		assertEquals(5, result.size());
+
+		List<String> expectedId = Arrays.asList("hapi-1", "hapi-2",  "hapi-0", "hapi-3", "hapi-4");
+		assertTrue(result.stream().allMatch((it) -> expectedId.contains(it.getIdElement().getIdPart())));
+
+		//_offset=5
+		List<IBaseResource> result2 = new ArrayList<>();
+		Map<String, String[]> parametersMap = new HashMap<>();
+		parametersMap.put("_offset", new String[]{"5"});
+		when(mySrd.getParameters()).thenReturn(parametersMap);
+		mySvc.listResources(mySrd, "Patient", Collections.singletonList(argument), result2);
+
+		assertFalse(result2.isEmpty());
+		assertEquals(5, result2.size());
+
+		List<String> expectedId2 = Arrays.asList("hapi-5", "hapi-6",  "hapi-7", "hapi-8", "hapi-9");
+		assertTrue(result2.stream().allMatch((it) -> expectedId2.contains(it.getIdElement().getIdPart())));
+	}
 }

hapi-fhir-storage/src/main/java/ca/uhn/fhir/jpa/graphql/DaoRegistryGraphQLStorageServices.java

@@ -46,6 +46,7 @@ import ca.uhn.fhir.rest.param.TokenParam;
 import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException;
 import ca.uhn.fhir.rest.server.exceptions.NotImplementedOperationException;
 import ca.uhn.fhir.rest.server.util.ISearchParamRegistry;
+import org.apache.commons.lang3.Validate;
 import org.hl7.fhir.exceptions.FHIRException;
 import org.hl7.fhir.instance.model.api.IBaseBundle;
 import org.hl7.fhir.instance.model.api.IBaseReference;
@@ -189,11 +190,15 @@ public class DaoRegistryGraphQLStorageServices implements IGraphQLStorageService
 
 		RequestDetails requestDetails = (RequestDetails) theAppInfo;
 		IBundleProvider response = dao.search(params, requestDetails);
-		int size = response.sizeOrThrowNpe();
+		Integer size = response.size();
-		if (response.preferredPageSize() != null && response.preferredPageSize() < size) {
+		//We set size to null in SearchCoordinatorSvcImpl.executeQuery() if matching results exceeds count
+		//so don't throw here
+		if ((response.preferredPageSize() != null && size != null && response.preferredPageSize() < size) ||
+			size == null) {
 			size = response.preferredPageSize();
 		}
 
+		Validate.notNull(size, "size is null");
 		theMatches.addAll(response.getResources(0, size));
 
 	}