Add DAO setting to specify maximum query size

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

@@ -104,7 +104,7 @@ public abstract class BaseHapiFhirSystemDao<T, MT> extends BaseHapiFhirDao<IBase
 
 				TypedQuery<Long> q = myEntityManager.createQuery("SELECT t.myId FROM ResourceTable t WHERE t.myIndexStatus IS NULL", Long.class);
 
-				ourLog.info("Beginning indexing query with maximum {}", maxResult);
+				ourLog.debug("Beginning indexing query with maximum {}", maxResult);
 				q.setMaxResults(maxResult);
 				Collection<Long> resources = q.getResultList();
 
@@ -145,9 +145,14 @@ public abstract class BaseHapiFhirSystemDao<T, MT> extends BaseHapiFhirDao<IBase
 				}
 
 				long delay = System.currentTimeMillis() - start;
-				long avg = count > 0 ? (delay / count) : 0;
+				long avg;
-				ourLog.info("Indexed {} resources in {}ms - Avg {}ms / resource", new Object[] { count, delay, avg });
+				if (count > 0) {
-
+					avg = (delay / count);
+					ourLog.info("Indexed {} resources in {}ms - Avg {}ms / resource", new Object[] { count, delay, avg });
+				} else {
+					ourLog.debug("Indexed 0 resources in {}ms", delay);
+				}
+				
 				return count;
 			}
 		});

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

@@ -64,21 +64,21 @@ public class DaoConfig {
 	 */
 	public static final Long DEFAULT_REUSE_CACHED_SEARCH_RESULTS_FOR_MILLIS = DateUtils.MILLIS_PER_MINUTE;
 
-	// ***
+	/**
-	// update setter javadoc if default changes
+	 * update setter javadoc if default changes
-	// ***
+	 */
 	private boolean myAllowExternalReferences = false;
 
-	// ***
+	/**
-	// update setter javadoc if default changes
+	 * update setter javadoc if default changes
-	// ***
+	 */
 	private boolean myAllowInlineMatchUrlReferences = true;
 	private boolean myAllowMultipleDelete;
 	private boolean myDefaultSearchParamsCanBeOverridden = false;
 
-	// ***
+	/**
-	// update setter javadoc if default changes
+	 * update setter javadoc if default changes
-	// ***
+	 */
 	private int myDeferIndexingForCodesystemsOfSize = 2000;
 
 	private boolean myDeleteStaleSearches = true;
@@ -87,27 +87,34 @@ public class DaoConfig {
 
 	private boolean myEnforceReferentialIntegrityOnWrite = true;
 
-	// ***
+	/**
-	// update setter javadoc if default changes
+	 * update setter javadoc if default changes
-	// ***
+	 */
 	private long myExpireSearchResultsAfterMillis = DateUtils.MILLIS_PER_HOUR;
-	private int myHardTagListLimit = 1000;
+	/**
+	 * update setter javadoc if default changes
+	 */
+	private Integer myFetchSizeDefaultMaximum = null;
 
+	private int myHardTagListLimit = 1000;
 	private int myIncludeLimit = 2000;
-	// ***
+	/**
-	// update setter javadoc if default changes
+	 * update setter javadoc if default changes
-	// ***
+	 */
 	private boolean myIndexContainedResources = true;
 	private List<IServerInterceptor> myInterceptors;
-	// ***
+	/**
-	// update setter javadoc if default changes
+	 * update setter javadoc if default changes
-	// ***
+	 */
 	private int myMaximumExpansionSize = 5000;
 	private int myMaximumSearchResultCountInTransaction = DEFAULT_MAXIMUM_SEARCH_RESULT_COUNT_IN_TRANSACTION;
 	private ResourceEncodingEnum myResourceEncoding = ResourceEncodingEnum.JSONC;
 	private Long myReuseCachedSearchResultsForMillis = DEFAULT_REUSE_CACHED_SEARCH_RESULTS_FOR_MILLIS;
 	private boolean mySchedulingDisabled;
 	private boolean mySubscriptionEnabled;
+	/**
+	 * update setter javadoc if default changes
+	 */
 	private long mySubscriptionPollDelay = 1000;
 	private Long mySubscriptionPurgeInactiveAfterMillis;
 	private boolean mySuppressUpdatesWithNoChange = true;
@@ -160,6 +167,20 @@ public class DaoConfig {
 		return myExpireSearchResultsAfterMillis;
 	}
 
+	/**
+	 * Gets the default maximum number of results to load in a query.
+	 * <p>
+	 * For example, if the database has a million Patient resources in it, and
+	 * the client requests <code>GET /Patient</code>, if this value is set
+	 * to a non-null value (default is <code>null</code>) only this number
+	 * of results will be fetched. Setting this value appropriately
+	 * can be useful to improve performance in some situations.
+	 * </p>
+	 */
+	public Integer getFetchSizeDefaultMaximum() {
+		return myFetchSizeDefaultMaximum;
+	}
+
 	/**
 	 * Gets the maximum number of results to return in a GetTags query (DSTU1 only)
 	 */
@@ -549,6 +570,20 @@ public class DaoConfig {
 		myExpireSearchResultsAfterMillis = theExpireSearchResultsAfterMillis;
 	}
 
+	/**
+	 * Gets the default maximum number of results to load in a query.
+	 * <p>
+	 * For example, if the database has a million Patient resources in it, and
+	 * the client requests <code>GET /Patient</code>, if this value is set
+	 * to a non-null value (default is <code>null</code>) only this number
+	 * of results will be fetched. Setting this value appropriately
+	 * can be useful to improve performance in some situations.
+	 * </p>
+	 */
+	public void setFetchSizeDefaultMaximum(Integer theFetchSizeDefaultMaximum) {
+		myFetchSizeDefaultMaximum = theFetchSizeDefaultMaximum;
+	}
+
 	/**
 	 * Do not call this method, it exists only for legacy reasons. It
 	 * will be removed in a future version. Configure the page size on your

hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/dstu3/FhirResourceDaoDstu3SearchNoFtTest.java

@@ -82,8 +82,7 @@ import org.springframework.transaction.TransactionStatus;
 import org.springframework.transaction.support.TransactionCallback;
 import org.springframework.transaction.support.TransactionTemplate;
 
-import ca.uhn.fhir.jpa.dao.BaseHapiFhirDao;
+import ca.uhn.fhir.jpa.dao.*;
-import ca.uhn.fhir.jpa.dao.SearchParameterMap;
 import ca.uhn.fhir.jpa.dao.SearchParameterMap.EverythingModeEnum;
 import ca.uhn.fhir.jpa.entity.ResourceIndexedSearchParamDate;
 import ca.uhn.fhir.jpa.entity.ResourceIndexedSearchParamNumber;
@@ -130,6 +129,7 @@ public class FhirResourceDaoDstu3SearchNoFtTest extends BaseJpaDstu3Test {
 	@Before
 	public void beforeDisableResultReuse() {
 		myDaoConfig.setReuseCachedSearchResultsForMillis(null);
+		myDaoConfig.setFetchSizeDefaultMaximum(new DaoConfig().getFetchSizeDefaultMaximum());
 	}
 
 	/**
@@ -1852,6 +1852,22 @@ public class FhirResourceDaoDstu3SearchNoFtTest extends BaseJpaDstu3Test {
 		assertThat(patients, not(containsInAnyOrder(pid2)));
 	}
 	
+	@Test
+	public void testSearchWithFetchSizeDefaultMaximum() {
+		myDaoConfig.setFetchSizeDefaultMaximum(5);
+		
+		for (int i = 0; i < 10; i++) {
+			Patient p = new Patient();
+			p.addName().setFamily("PT" + i);
+			myPatientDao.create(p);
+		}
+		
+		SearchParameterMap map = new SearchParameterMap();
+		map.setLoadSynchronous(true);
+		IBundleProvider values = myPatientDao.search(map);
+		assertEquals(5, values.size().intValue());
+		assertEquals(5, values.getResources(0, 1000).size());
+	}
 	
 	@Test
 	public void testSearchStringParam() throws Exception {

src/changes/changes.xml

@@ -28,6 +28,13 @@
 				Optimize queries in JPA server remove a few redundant select columns when performing
 				searches. This provides a slight speed increase in some cases.
 			</action>
+			<action type="add">
+				Add configuration to JPA server DaoConfig that allows a maximum
+				number of search results to be specified. Queries will never return
+				more than this number, which can be good for avoiding accidental 
+				performance problems in situations where lare queries should not be 
+				needed
+			</action>
 		</release>
 		<release version="2.5" date="2017-06-08">
 			<action type="fix">