Support retry of $reindex version conflict (#4603)

* Support retry of $reindex conflict
* Notes and cleanup of Phaser

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/6_6_0/4603-reindex-retry.yaml

@@ -0,0 +1,5 @@
+---
+type: change
+issue: 4603
+title: "Transaction retry will now also apply to ObjectOptimisticLockingFailureException.  This enables retry of
+  $reindex work chunks when they collide with a DELETE operation."

hapi-fhir-jpaserver-test-r4/src/test/java/ca/uhn/fhir/jpa/search/reindex/ReindexRaceBugTest.java

@@ -8,8 +8,11 @@ import ca.uhn.fhir.rest.api.server.RequestDetails;
 import ca.uhn.fhir.rest.api.server.SystemRequestDetails;
 import ca.uhn.fhir.rest.api.server.storage.TransactionDetails;
 import ca.uhn.fhir.rest.server.exceptions.ResourceGoneException;
+import ca.uhn.fhir.rest.server.exceptions.ResourceVersionConflictException;
 import ca.uhn.fhir.storage.test.DaoTestDataBuilder;
 import ca.uhn.test.concurrency.LockstepEnumPhaser;
+import org.apache.commons.lang3.concurrent.BasicThreadFactory;
+import org.hamcrest.Matchers;
 import org.hl7.fhir.instance.model.api.IIdType;
 import org.hl7.fhir.r4.model.Observation;
 import org.hl7.fhir.r4.model.SearchParameter;
@@ -21,15 +24,15 @@ import org.springframework.test.context.ContextConfiguration;
 import org.springframework.transaction.TransactionStatus;
 import org.springframework.transaction.annotation.Propagation;
 
-import javax.annotation.Nonnull;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
-import java.util.concurrent.ThreadFactory;
 import java.util.function.BiFunction;
 
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.fail;
 
 @ContextConfiguration(classes = {
@@ -49,12 +52,12 @@ class ReindexRaceBugTest extends BaseJpaR4Test {
 	 * The $reindex step processes several resources in a single tx.
 	 * The tested sequence here is: job step $reindexes a resouce, then another thread DELETEs the resource,
 	 * then later, the $reindex step finishes the rest of the resources and commits AFTER the DELETE commits.
-	 *
+	 * This scenario could insert index rows into HFJ_SPIDX_TOKEN even though the resource was gone.
-	 * This was inserting new index rows into HFJ_SPIDX_TOKEN even though the resource was gone.
 	 * This is an illegal state for our index.  Deleted resources should never have content in HFJ_SPIDX_*
+	 * Fixed by taking an optimistic lock on hfj_resource even though $reindex is read-only on that table.
 	 */
 	@Test
-	void deleteOverlapsWithReindex_leavesIndexRowsP() throws InterruptedException, ExecutionException {
+	void deleteOverlapsWithReindex_leavesIndexRowsP() {
 		LockstepEnumPhaser<Steps> phaser = new LockstepEnumPhaser<>(2, Steps.class);
 
 		ourLog.info("An observation is created");
@@ -90,10 +93,8 @@ class ReindexRaceBugTest extends BaseJpaR4Test {
 
 		assertEquals(1, getSPIDXDateCount(observationPid), "still only one index row before reindex");
 
-
 		// suppose reindex job step starts here and loads the resource and ResourceTable entity
-		ThreadFactory loggingThreadFactory = getLoggingThreadFactory("Reindex-thread");
+		ExecutorService backgroundReindexThread = Executors.newSingleThreadExecutor(new BasicThreadFactory.Builder().namingPattern("Reindex-thread-%d").build());
-		ExecutorService backgroundReindexThread = Executors.newSingleThreadExecutor(loggingThreadFactory);
 		Future<Integer> backgroundResult = backgroundReindexThread.submit(() -> {
 			try {
 				callInFreshTx((tx, rd) -> {
@@ -120,6 +121,7 @@ class ReindexRaceBugTest extends BaseJpaR4Test {
 					return 0;
 				});
 			} finally {
+				ourLog.info("$reindex commit complete");
 				phaser.arriveAndAwaitSharedEndOf(Steps.COMMIT_REINDEX);
 			}
 			return 1;
@@ -131,9 +133,8 @@ class ReindexRaceBugTest extends BaseJpaR4Test {
 		phaser.arriveAndAwaitSharedEndOf(Steps.RUN_REINDEX);
 
 		// then the resource is deleted
-		phaser.assertInPhase(Steps.RUN_DELETE);
-
 		ourLog.info("Deleting observation");
+		phaser.assertInPhase(Steps.RUN_DELETE);
 		callInFreshTx((tx, rd) -> myObservationDao.delete(observationId, rd));
 		assertResourceDeleted(observationId);
 		assertEquals(0, getSPIDXDateCount(observationPid), "A deleted resource should have 0 index rows");
@@ -146,22 +147,12 @@ class ReindexRaceBugTest extends BaseJpaR4Test {
 		phaser.arriveAndAwaitSharedEndOf(Steps.COMMIT_REINDEX);
 
 		assertEquals(0, getSPIDXDateCount(observationPid), "A deleted resource should still have 0 index rows, after $reindex completes");
-	}
 
-	@Nonnull
+		// Verify the exception from $reindex
-	static ThreadFactory getLoggingThreadFactory(String theThreadName) {
+		// In a running server, we expect UserRequestRetryVersionConflictsInterceptor to cause a retry inside the ReindexStep
-		ThreadFactory loggingThreadFactory = r -> new Thread(() -> {
+		// But here in the test, we have not configured any retry logic.
-			boolean success = false;
+		ExecutionException e = assertThrows(ExecutionException.class, backgroundResult::get, "Optimistic locking detects the DELETE and rolls back");
-			try {
+		assertThat("Hapi maps conflict exception type", e.getCause(), Matchers.instanceOf(ResourceVersionConflictException.class));
-				r.run();
-				success = true;
-			} finally {
-				if (!success) {
-					ourLog.error("Background thread failed");
-				}
-			}
-		}, theThreadName);
-		return loggingThreadFactory;
 	}
 
 	void assertResourceDeleted(IIdType observationId) {

hapi-fhir-storage/src/main/java/ca/uhn/fhir/jpa/dao/tx/HapiTransactionService.java

@@ -45,6 +45,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.dao.DataIntegrityViolationException;
+import org.springframework.orm.ObjectOptimisticLockingFailureException;
 import org.springframework.transaction.PlatformTransactionManager;
 import org.springframework.transaction.TransactionStatus;
 import org.springframework.transaction.annotation.Isolation;
@@ -222,7 +223,7 @@ public class HapiTransactionService implements IHapiTransactionService {
 
 					return doExecuteCallback(theExecutionBuilder, theCallback);
 
-				} catch (ResourceVersionConflictException | DataIntegrityViolationException e) {
+				} catch (ResourceVersionConflictException | DataIntegrityViolationException | ObjectOptimisticLockingFailureException e) {
 					ourLog.debug("Version conflict detected", e);
 
 					if (theExecutionBuilder.myOnRollback != null) {

hapi-fhir-test-utilities/src/main/java/ca/uhn/test/concurrency/LockstepEnumPhaser.java

@@ -9,17 +9,16 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.fail;
 
 /**
- * Test helper to force a particular sequence on 2 or more threads.
+ * Test helper to force a particular sequence on multiple threads.
  * Wraps Phaser with an Enum for better messages, and some test support.
  * The only use is to impose a particular execution sequence over multiple threads when reproducing bugs.
- *
+ * <p>
  * The simplest usage is to declare the number of collaborators as theParticipantCount
  * in the constructor, and then have each participant thread call {@link #arriveAndAwaitSharedEndOf}
  * as they finish the work of every phase.
  * Every thread needs to confirm, even if they do no work in that phase.
  * <p>
  * Note: this is just a half-baked wrapper around Phaser.
- * The behaviour is not especially precise, or tested. Comments welcome: MB.
  *
  * @param <E> an enum used to name the phases.
  */
@@ -35,60 +34,72 @@ public class LockstepEnumPhaser<E extends Enum<E>> {
 		myEnumConstants = myEnumClass.getEnumConstants();
 	}
 
-	public E arrive() {
-		E result = phaseToEnum(myPhaser.arrive());
-		ourLog.info("Arrive in phase {}", result);
-		return result;
-	}
-
 	public void assertInPhase(E theStageEnum) {
 		assertEquals(theStageEnum, getPhase(), "In stage " + theStageEnum);
 	}
 
+	/**
+	 * Get the current phase.
+	 */
 	public E getPhase() {
 		return phaseToEnum(myPhaser.getPhase());
 	}
 
-	public E awaitAdvance(E thePhase) {
+	/**
+	 * Declare that this thread-participant has finished the work of thePhase,
+	 * and then wait until all other participants have also finished.
+	 *
+	 * @param thePhase the phase the thread just completed
+	 * @return the new phase starting.
+	 */
+	public E arriveAndAwaitSharedEndOf(E thePhase) {
 		checkAwait(thePhase);
+		E current = arrive();
+		assertEquals(thePhase, current);
 		return doAwait(thePhase);
 	}
 
 	/**
-	 * Like arrive(), but verify stage first
+	 * Finish a phase, and deregister so that later stages can complete
+	 * with a reduced participant count.
 	 */
-	public E arriveAtMyEndOf(E thePhase) {
-		assertInPhase(thePhase);
-		return arrive();
-	}
-
-	public E arriveAndAwaitSharedEndOf(E thePhase) {
-		checkAwait(thePhase);
-		arrive();
-		return doAwait(thePhase);
-	}
-
 	public E arriveAndDeregister() {
 		return phaseToEnum(myPhaser.arriveAndDeregister());
 	}
 
+	/**
+	 * Add a new participant to the pool.
+	 * Later await calls will wait for one more arrival before proceeding.
+	 */
 	public E register() {
 		return phaseToEnum(myPhaser.register());
 	}
 
+	E arrive() {
+		E result = phaseToEnum(myPhaser.arrive());
+		ourLog.info("Arrive to my end of phase {}", result);
+		return result;
+	}
+
+
 	private E doAwait(E thePhase) {
 		ourLog.debug("Start doAwait - {}", thePhase);
 		E phase = phaseToEnum(myPhaser.awaitAdvance(thePhase.ordinal()));
-		ourLog.info("Finish doAwait - {}", thePhase);
+		ourLog.info("Done waiting for end of {}.  Now starting {}", thePhase, getPhase());
 		return phase;
 	}
 
+	/**
+	 * Defensively verify that the phase we are waiting to end is actually the current phase.
+	 */
 	private void checkAwait(E thePhase) {
 		E currentPhase = getPhase();
 		if (currentPhase.ordinal() < thePhase.ordinal()) {
-			fail("Can't wait for end of phase " + thePhase + ", still in phase " + currentPhase);
+			// Explicitly progressing lock-step is safer for most tests.
+			// But we could allow waiting multiple phases with a loop here instead of failing. MB
+			fail(String.format("Can't wait for end of phase %s, still in phase %s", thePhase, currentPhase));
 		} else if (currentPhase.ordinal() > thePhase.ordinal()) {
-			ourLog.warn("Skip waiting for phase {}, already in phase {}", thePhase, currentPhase);
+			fail(String.format("Can't wait for end of phase %s, already in phase %s", thePhase, currentPhase));
 		}
 	}
 

hapi-fhir-test-utilities/src/test/java/ca/uhn/test/concurrency/LockstepEnumPhaserTest.java

@@ -8,6 +8,7 @@ import org.junit.jupiter.api.Timeout;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import javax.annotation.Nonnull;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
@@ -26,6 +27,9 @@ import static ca.uhn.test.concurrency.LockstepEnumPhaserTest.Stages.TWO;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
+// All of these should run pretty quickly - 5s should be lots.
+// But if they deadlock, they will hang forever.  Need @Timeout.
+@Timeout(5)
 class LockstepEnumPhaserTest {
 	private static final Logger ourLog = LoggerFactory.getLogger(LockstepEnumPhaserTest.class);
 	final ExecutorService myExecutorService = Executors.newFixedThreadPool(10);
@@ -39,7 +43,6 @@ class LockstepEnumPhaserTest {
 
 	LockstepEnumPhaser<Stages> myPhaser;
 
-	@Timeout(1)
 	@Test
 	void phaserWithOnePariticpant_worksFine() {
 	    // given
@@ -47,7 +50,7 @@ class LockstepEnumPhaserTest {
 
 		myPhaser.assertInPhase(ONE);
 
-		myPhaser.arriveAtMyEndOf(ONE);
+		myPhaser.arriveAndAwaitSharedEndOf(ONE);
 
 		myPhaser.arriveAndAwaitSharedEndOf(TWO);
 
@@ -56,7 +59,6 @@ class LockstepEnumPhaserTest {
 		myPhaser.assertInPhase(FINISHED);
 	}
 
-	@Timeout(5)
 	@Test
 	void phaserWithTwoThreads_runsInLockStep() throws InterruptedException, ExecutionException {
 		// given
@@ -82,10 +84,7 @@ class LockstepEnumPhaserTest {
 			myPhaser.assertInPhase(THREE);
 			recordProgress(threadId);
 
-			Stages nextStage = myPhaser.awaitAdvance(TWO);
+			myPhaser.arriveAndAwaitSharedEndOf(THREE);
-			assertEquals(THREE, nextStage);
-
-			myPhaser.arriveAtMyEndOf(THREE);
 
 			ourLog.info("Finished");
 
@@ -104,33 +103,13 @@ class LockstepEnumPhaserTest {
 		myProgressEvents.add(Pair.of(threadId, myPhaser.getPhase()));
 	}
 
-	@Timeout(5)
 	@Test
 	void phaserWithTwoThreads_canAddThird_sequencContinues() throws InterruptedException, ExecutionException {
 		// given
 		myPhaser = new LockstepEnumPhaser<>(2, Stages.class);
 
 		// run one simple schedule
-		Callable<Integer> schedule1 = ()->{
+		Callable<Integer> schedule1 = buildSimpleCountingSchedule(1);
-			int threadId = 1;
-			ourLog.info("Starting schedule1");
-			myPhaser.assertInPhase(ONE);
-			recordProgress(threadId);
-
-			myPhaser.arriveAndAwaitSharedEndOf(ONE);
-
-			recordProgress(threadId);
-
-			myPhaser.arriveAndAwaitSharedEndOf(TWO);
-
-			recordProgress(threadId);
-
-			myPhaser.arriveAndAwaitSharedEndOf(THREE);
-
-			ourLog.info("Finished schedule1");
-
-			return 1;
-		};
 		// this schedule will start half-way in
 		Callable<Integer> schedule2 = ()->{
 			int threadId = 2;
@@ -149,7 +128,7 @@ class LockstepEnumPhaserTest {
 
 			ourLog.info("Finished schedule2");
 
-			return 1;
+			return 2;
 		};
 		// this schedule will start schedule 2 half-way
 		Callable<Integer> schedule3 = ()->{
@@ -174,17 +153,83 @@ class LockstepEnumPhaserTest {
 
 			ourLog.info("Finished schedule3");
 
-			return 1;
+			return 3;
 		};
 		Future<Integer> result1 = myExecutorService.submit(schedule1);
-		Future<Integer> result2 = myExecutorService.submit(schedule3);
+		Future<Integer> result3 = myExecutorService.submit(schedule3);
 
 		assertEquals(1, result1.get());
-		assertEquals(1, result2.get());
+		assertEquals(3, result3.get());
 
 		assertThat("progress is ordered", myProgressEvents, OrderMatchers.softOrdered(myProgressStageComparator));
 		assertThat("all progress logged", myProgressEvents, Matchers.hasSize(8));
 
 	}
 
+	@Nonnull
+	private Callable<Integer> buildSimpleCountingSchedule(int theThreadId) {
+		Callable<Integer> schedule = ()->{
+			ourLog.info("Starting schedule - {}", theThreadId);
+
+			myPhaser.assertInPhase(ONE);
+			recordProgress(theThreadId);
+
+			myPhaser.arriveAndAwaitSharedEndOf(ONE);
+
+			recordProgress(theThreadId);
+
+			myPhaser.arriveAndAwaitSharedEndOf(TWO);
+
+			recordProgress(theThreadId);
+
+			myPhaser.arriveAndAwaitSharedEndOf(THREE);
+
+			ourLog.info("Finished schedule1");
+
+			return theThreadId;
+		};
+		return schedule;
+	}
+
+	@Test
+	void aShortScheduleDeregister_allowsRemainingParticipantsToContinue() throws ExecutionException, InterruptedException {
+		// given
+		myPhaser = new LockstepEnumPhaser<>(3, Stages.class);
+
+		// Three schedules, but with one that leaves early
+		// sched 1,2 counting
+		// sched 3 start, but end with 2.
+		Callable<Integer> schedule1 = buildSimpleCountingSchedule(1);
+		Callable<Integer> schedule2 = buildSimpleCountingSchedule(2);
+		Callable<Integer> schedule3 = () -> {
+			int threadId = 3;
+			ourLog.info("Starting schedule - {}", threadId);
+
+			myPhaser.assertInPhase(ONE);
+			recordProgress(threadId);
+
+			myPhaser.arriveAndAwaitSharedEndOf(ONE);
+
+			recordProgress(threadId);
+
+			ourLog.info("Leaving schedule - {}", threadId);
+
+			Stages deregisterPhase = myPhaser.arriveAndDeregister();
+			assertEquals(TWO, deregisterPhase);
+
+			return threadId;
+		};
+		Future<Integer> result1 = myExecutorService.submit(schedule1);
+		Future<Integer> result2 = myExecutorService.submit(schedule2);
+		Future<Integer> result3 = myExecutorService.submit(schedule3);
+
+		assertEquals(1, result1.get());
+		assertEquals(2, result2.get());
+		assertEquals(3, result3.get());
+
+		assertThat("progress is ordered", myProgressEvents, OrderMatchers.softOrdered(myProgressStageComparator));
+		assertThat("all progress logged", myProgressEvents, Matchers.hasSize(2*3 + 2));
+
+	}
+
 }