opendaylight/md-sal/sal-distributed-datastore/src/test/java/org/opendaylight/controller/cluster/datastore/AbstractShardTest.java

   1 /*
   2  * Copyright (c) 2015 Brocade Communications Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.cluster.datastore;
   9
  10 import static org.junit.Assert.assertEquals;
  11 import static org.junit.Assert.assertNotNull;
  12 import static org.junit.Assert.assertTrue;
  13 import static org.junit.Assert.fail;
  14 import static org.mockito.ArgumentMatchers.any;
  15 import static org.mockito.ArgumentMatchers.nullable;
  16 import static org.mockito.Mockito.doAnswer;
  17 import static org.mockito.Mockito.doReturn;
  18 import static org.mockito.Mockito.mock;
  19 import static org.opendaylight.controller.cluster.datastore.DataStoreVersions.CURRENT_VERSION;
  20 import static org.opendaylight.controller.cluster.datastore.ShardDataTreeMocking.successfulCanCommit;
  21 import static org.opendaylight.controller.cluster.datastore.ShardDataTreeMocking.successfulCommit;
  22 import static org.opendaylight.controller.cluster.datastore.ShardDataTreeMocking.successfulPreCommit;
  23
  24 import akka.actor.ActorRef;
  25 import akka.actor.PoisonPill;
  26 import akka.actor.Props;
  27 import akka.dispatch.Dispatchers;
  28 import akka.japi.Creator;
  29 import akka.pattern.Patterns;
  30 import akka.testkit.TestActorRef;
  31 import akka.util.Timeout;
  32 import com.google.common.primitives.UnsignedLong;
  33 import com.google.common.util.concurrent.FutureCallback;
  34 import com.google.common.util.concurrent.Uninterruptibles;
  35 import java.io.IOException;
  36 import java.util.Collections;
  37 import java.util.HashMap;
  38 import java.util.Map;
  39 import java.util.Optional;
  40 import java.util.Set;
  41 import java.util.SortedSet;
  42 import java.util.concurrent.CountDownLatch;
  43 import java.util.concurrent.ExecutionException;
  44 import java.util.concurrent.TimeUnit;
  45 import java.util.concurrent.TimeoutException;
  46 import java.util.concurrent.atomic.AtomicInteger;
  47 import org.junit.After;
  48 import org.junit.Assert;
  49 import org.junit.Before;
  50 import org.opendaylight.controller.cluster.access.concepts.MemberName;
  51 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  52 import org.opendaylight.controller.cluster.datastore.DatastoreContext.Builder;
  53 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  54 import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
  55 import org.opendaylight.controller.cluster.datastore.messages.ForwardedReadyTransaction;
  56 import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
  57 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  58 import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
  59 import org.opendaylight.controller.cluster.datastore.persisted.CommitTransactionPayload;
  60 import org.opendaylight.controller.cluster.datastore.persisted.MetadataShardDataTreeSnapshot;
  61 import org.opendaylight.controller.cluster.datastore.persisted.ShardSnapshotState;
  62 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  63 import org.opendaylight.controller.cluster.raft.TestActorFactory;
  64 import org.opendaylight.controller.cluster.raft.persisted.Snapshot;
  65 import org.opendaylight.controller.cluster.raft.utils.InMemoryJournal;
  66 import org.opendaylight.controller.cluster.raft.utils.InMemorySnapshotStore;
  67 import org.opendaylight.controller.md.cluster.datastore.model.CarsModel;
  68 import org.opendaylight.controller.md.cluster.datastore.model.TestModel;
  69 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  70 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  71 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  72 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  73 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  74 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  75 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  76 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateNode;
  77 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateTip;
  78 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeConfiguration;
  79 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  80 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
  81 import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
  82 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  83 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
  84 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  85 import scala.concurrent.Await;
  86 import scala.concurrent.Future;
  87 import scala.concurrent.duration.FiniteDuration;
  88
  89 /**
  90  * Abstract base for shard unit tests.
  91  *
  92  * @author Thomas Pantelis
  93  */
  94 public abstract class AbstractShardTest extends AbstractActorTest {
  95     protected static final SchemaContext SCHEMA_CONTEXT = TestModel.createTestContext();
  96
  97     private static final AtomicInteger NEXT_SHARD_NUM = new AtomicInteger();
  98
  99     protected static final int HEARTBEAT_MILLIS = 100;
 100
 101     protected final ShardIdentifier shardID = ShardIdentifier.create("inventory", MemberName.forName("member-1"),
 102         "config" + NEXT_SHARD_NUM.getAndIncrement());
 103
 104     protected final Builder dataStoreContextBuilder = DatastoreContext.newBuilder()
 105             .shardJournalRecoveryLogBatchSize(3).shardSnapshotBatchCount(5000)
 106             .shardHeartbeatIntervalInMillis(HEARTBEAT_MILLIS);
 107
 108     protected final TestActorFactory actorFactory = new TestActorFactory(getSystem());
 109
 110     @Before
 111     public void setUp() {
 112         InMemorySnapshotStore.clear();
 113         InMemoryJournal.clear();
 114     }
 115
 116     @After
 117     public void tearDown() {
 118         InMemorySnapshotStore.clear();
 119         InMemoryJournal.clear();
 120         actorFactory.close();
 121     }
 122
 123     protected DatastoreContext newDatastoreContext() {
 124         return dataStoreContextBuilder.build();
 125     }
 126
 127     protected Props newShardProps() {
 128         return newShardBuilder().props();
 129     }
 130
 131     protected Shard.Builder newShardBuilder() {
 132         return Shard.builder().id(shardID).datastoreContext(newDatastoreContext())
 133             .schemaContextProvider(() -> SCHEMA_CONTEXT);
 134     }
 135
 136     protected void testRecovery(final Set<Integer> listEntryKeys) throws Exception {
 137         // Create the actor and wait for recovery complete.
 138
 139         final int nListEntries = listEntryKeys.size();
 140
 141         final CountDownLatch recoveryComplete = new CountDownLatch(1);
 142
 143         final Creator<Shard> creator = () -> new Shard(newShardBuilder()) {
 144             @Override
 145             protected void onRecoveryComplete() {
 146                 try {
 147                     super.onRecoveryComplete();
 148                 } finally {
 149                     recoveryComplete.countDown();
 150                 }
 151             }
 152         };
 153
 154         final TestActorRef<Shard> shard = TestActorRef.create(getSystem(),
 155                 Props.create(new DelegatingShardCreator(creator)).withDispatcher(Dispatchers.DefaultDispatcherId()),
 156                 "testRecovery");
 157
 158         assertTrue("Recovery complete", recoveryComplete.await(5, TimeUnit.SECONDS));
 159
 160         // Verify data in the data store.
 161
 162         final NormalizedNode<?, ?> outerList = readStore(shard, TestModel.OUTER_LIST_PATH);
 163         assertNotNull(TestModel.OUTER_LIST_QNAME.getLocalName() + " not found", outerList);
 164         assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " value is not Iterable",
 165                 outerList.getValue() instanceof Iterable);
 166         for (final Object entry: (Iterable<?>) outerList.getValue()) {
 167             assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " entry is not MapEntryNode",
 168                     entry instanceof MapEntryNode);
 169             final MapEntryNode mapEntry = (MapEntryNode)entry;
 170             final Optional<DataContainerChild<? extends PathArgument, ?>> idLeaf =
 171                     mapEntry.getChild(new YangInstanceIdentifier.NodeIdentifier(TestModel.ID_QNAME));
 172             assertTrue("Missing leaf " + TestModel.ID_QNAME.getLocalName(), idLeaf.isPresent());
 173             final Object value = idLeaf.get().getValue();
 174             assertTrue("Unexpected value for leaf " + TestModel.ID_QNAME.getLocalName() + ": " + value,
 175                     listEntryKeys.remove(value));
 176         }
 177
 178         if (!listEntryKeys.isEmpty()) {
 179             fail("Missing " + TestModel.OUTER_LIST_QNAME.getLocalName() + " entries with keys: " + listEntryKeys);
 180         }
 181
 182         assertEquals("Last log index", nListEntries,
 183                 shard.underlyingActor().getShardMBean().getLastLogIndex());
 184         assertEquals("Commit index", nListEntries,
 185                 shard.underlyingActor().getShardMBean().getCommitIndex());
 186         assertEquals("Last applied", nListEntries,
 187                 shard.underlyingActor().getShardMBean().getLastApplied());
 188
 189         shard.tell(PoisonPill.getInstance(), ActorRef.noSender());
 190     }
 191
 192     protected void verifyLastApplied(final TestActorRef<Shard> shard, final long expectedValue) {
 193         long lastApplied = -1;
 194         for (int i = 0; i < 20 * 5; i++) {
 195             lastApplied = shard.underlyingActor().getShardMBean().getLastApplied();
 196             if (lastApplied == expectedValue) {
 197                 return;
 198             }
 199             Uninterruptibles.sleepUninterruptibly(50, TimeUnit.MILLISECONDS);
 200         }
 201
 202         Assert.fail(String.format("Expected last applied: %d, Actual: %d", expectedValue, lastApplied));
 203     }
 204
 205     protected DataTree createDelegatingMockDataTree() throws Exception {
 206         final DataTree actual = new InMemoryDataTreeFactory().create(DataTreeConfiguration.DEFAULT_CONFIGURATION);
 207         final DataTree mock = mock(DataTree.class);
 208
 209         doAnswer(invocation -> {
 210             actual.validate(invocation.getArgument(0));
 211             return null;
 212         }).when(mock).validate(any(DataTreeModification.class));
 213
 214         doAnswer(invocation -> actual.prepare(invocation.getArgument(0))).when(
 215                 mock).prepare(any(DataTreeModification.class));
 216
 217         doAnswer(invocation -> {
 218             actual.commit(invocation.getArgument(0));
 219             return null;
 220         }).when(mock).commit(any(DataTreeCandidate.class));
 221
 222         doAnswer(invocation -> {
 223             actual.setSchemaContext(invocation.getArgument(0));
 224             return null;
 225         }).when(mock).setSchemaContext(any(SchemaContext.class));
 226
 227         doAnswer(invocation -> actual.takeSnapshot()).when(mock).takeSnapshot();
 228
 229         doAnswer(invocation -> actual.getRootPath()).when(mock).getRootPath();
 230
 231         return mock;
 232     }
 233
 234     protected ShardDataTreeCohort mockShardDataTreeCohort() {
 235         ShardDataTreeCohort cohort = mock(ShardDataTreeCohort.class);
 236         DataTreeCandidate candidate = mockCandidate("candidate");
 237         successfulCanCommit(cohort);
 238         successfulPreCommit(cohort, candidate);
 239         successfulCommit(cohort);
 240         doReturn(candidate).when(cohort).getCandidate();
 241         return cohort;
 242     }
 243
 244     protected Map<TransactionIdentifier, CapturingShardDataTreeCohort> setupCohortDecorator(final Shard shard,
 245             final TransactionIdentifier... transactionIDs) {
 246         final Map<TransactionIdentifier, CapturingShardDataTreeCohort> cohortMap = new HashMap<>();
 247         for (TransactionIdentifier id: transactionIDs) {
 248             cohortMap.put(id, new CapturingShardDataTreeCohort());
 249         }
 250
 251         shard.getCommitCoordinator().setCohortDecorator((transactionID, actual) -> {
 252             CapturingShardDataTreeCohort cohort = cohortMap.get(transactionID);
 253             cohort.setDelegate(actual);
 254             return cohort;
 255         });
 256
 257         return cohortMap;
 258     }
 259
 260     protected BatchedModifications prepareBatchedModifications(final TransactionIdentifier transactionID,
 261                                                                final MutableCompositeModification modification) {
 262         return prepareBatchedModifications(transactionID, modification, false);
 263     }
 264
 265     protected static BatchedModifications prepareBatchedModifications(final TransactionIdentifier transactionID,
 266                                                              final MutableCompositeModification modification,
 267                                                              final boolean doCommitOnReady) {
 268         final BatchedModifications batchedModifications = new BatchedModifications(transactionID, CURRENT_VERSION);
 269         batchedModifications.addModification(modification);
 270         batchedModifications.setReady();
 271         batchedModifications.setDoCommitOnReady(doCommitOnReady);
 272         batchedModifications.setTotalMessagesSent(1);
 273         return batchedModifications;
 274     }
 275
 276     protected static BatchedModifications prepareBatchedModifications(final TransactionIdentifier transactionID,
 277             final YangInstanceIdentifier path, final NormalizedNode<?, ?> data, final boolean doCommitOnReady) {
 278         final MutableCompositeModification modification = new MutableCompositeModification();
 279         modification.addModification(new WriteModification(path, data));
 280         return prepareBatchedModifications(transactionID, modification, doCommitOnReady);
 281     }
 282
 283     protected static ForwardedReadyTransaction prepareForwardedReadyTransaction(final TestActorRef<Shard> shard,
 284             final TransactionIdentifier transactionID, final YangInstanceIdentifier path,
 285             final NormalizedNode<?, ?> data, final boolean doCommitOnReady) {
 286         ReadWriteShardDataTreeTransaction rwTx = shard.underlyingActor().getDataStore()
 287                 .newReadWriteTransaction(transactionID);
 288         rwTx.getSnapshot().write(path, data);
 289         return new ForwardedReadyTransaction(transactionID, CURRENT_VERSION, rwTx, doCommitOnReady, Optional.empty());
 290     }
 291
 292     public static NormalizedNode<?,?> readStore(final TestActorRef<? extends Shard> shard,
 293             final YangInstanceIdentifier id) {
 294         return shard.underlyingActor().getDataStore().readNode(id).orElse(null);
 295     }
 296
 297     public static NormalizedNode<?,?> readStore(final DataTree store, final YangInstanceIdentifier id) {
 298         return store.takeSnapshot().readNode(id).orElse(null);
 299     }
 300
 301     public void writeToStore(final TestActorRef<Shard> shard, final YangInstanceIdentifier id,
 302             final NormalizedNode<?,?> node) throws InterruptedException, ExecutionException {
 303         Future<Object> future = Patterns.ask(shard, newBatchedModifications(nextTransactionId(),
 304                 id, node, true, true, 1), new Timeout(5, TimeUnit.SECONDS));
 305         try {
 306             Await.ready(future, FiniteDuration.create(5, TimeUnit.SECONDS));
 307         } catch (TimeoutException e) {
 308             throw new ExecutionException(e);
 309         }
 310     }
 311
 312     public static void writeToStore(final ShardDataTree store, final YangInstanceIdentifier id,
 313             final NormalizedNode<?,?> node) throws DataValidationFailedException {
 314         BatchedModifications batched = newBatchedModifications(nextTransactionId(), id, node, true, true, 1);
 315         DataTreeModification modification = store.getDataTree().takeSnapshot().newModification();
 316         batched.apply(modification);
 317         store.notifyListeners(commitTransaction(store.getDataTree(), modification));
 318     }
 319
 320     public static void writeToStore(final DataTree store, final YangInstanceIdentifier id,
 321             final NormalizedNode<?,?> node) throws DataValidationFailedException {
 322         final DataTreeModification transaction = store.takeSnapshot().newModification();
 323
 324         transaction.write(id, node);
 325         transaction.ready();
 326         store.validate(transaction);
 327         final DataTreeCandidate candidate = store.prepare(transaction);
 328         store.commit(candidate);
 329     }
 330
 331     public void mergeToStore(final ShardDataTree store, final YangInstanceIdentifier id,
 332             final NormalizedNode<?,?> node) throws DataValidationFailedException {
 333         final BatchedModifications batched = new BatchedModifications(nextTransactionId(), CURRENT_VERSION);
 334         batched.addModification(new MergeModification(id, node));
 335         batched.setReady();
 336         batched.setDoCommitOnReady(true);
 337         batched.setTotalMessagesSent(1);
 338
 339         DataTreeModification modification = store.getDataTree().takeSnapshot().newModification();
 340         batched.apply(modification);
 341         store.notifyListeners(commitTransaction(store.getDataTree(), modification));
 342     }
 343
 344     DataTree setupInMemorySnapshotStore() throws DataValidationFailedException {
 345         final DataTree testStore = new InMemoryDataTreeFactory().create(
 346             DataTreeConfiguration.DEFAULT_OPERATIONAL, SCHEMA_CONTEXT);
 347
 348         writeToStore(testStore, TestModel.TEST_PATH, ImmutableNodes.containerNode(TestModel.TEST_QNAME));
 349
 350         final NormalizedNode<?, ?> root = readStore(testStore, YangInstanceIdentifier.empty());
 351
 352         InMemorySnapshotStore.addSnapshot(shardID.toString(), Snapshot.create(
 353                 new ShardSnapshotState(new MetadataShardDataTreeSnapshot(root)),
 354                 Collections.<ReplicatedLogEntry>emptyList(), 0, 1, -1, -1, 1, null, null));
 355         return testStore;
 356     }
 357
 358     static CommitTransactionPayload payloadForModification(final DataTree source, final DataTreeModification mod,
 359             final TransactionIdentifier transactionId) throws DataValidationFailedException, IOException {
 360         source.validate(mod);
 361         final DataTreeCandidate candidate = source.prepare(mod);
 362         source.commit(candidate);
 363         return CommitTransactionPayload.create(transactionId, candidate);
 364     }
 365
 366     static BatchedModifications newBatchedModifications(final TransactionIdentifier transactionID,
 367             final YangInstanceIdentifier path, final NormalizedNode<?, ?> data, final boolean ready,
 368             final boolean doCommitOnReady, final int messagesSent) {
 369         final BatchedModifications batched = new BatchedModifications(transactionID, CURRENT_VERSION);
 370         batched.addModification(new WriteModification(path, data));
 371         if (ready) {
 372             batched.setReady();
 373         }
 374         batched.setDoCommitOnReady(doCommitOnReady);
 375         batched.setTotalMessagesSent(messagesSent);
 376         return batched;
 377     }
 378
 379     static BatchedModifications newReadyBatchedModifications(final TransactionIdentifier transactionID,
 380             final YangInstanceIdentifier path, final NormalizedNode<?, ?> data,
 381             final SortedSet<String> participatingShardNames) {
 382         final BatchedModifications batched = new BatchedModifications(transactionID, CURRENT_VERSION);
 383         batched.addModification(new WriteModification(path, data));
 384         batched.setReady(Optional.of(participatingShardNames));
 385         batched.setTotalMessagesSent(1);
 386         return batched;
 387     }
 388
 389     @SuppressWarnings("unchecked")
 390     static void verifyOuterListEntry(final TestActorRef<Shard> shard, final Object expIDValue) {
 391         final NormalizedNode<?, ?> outerList = readStore(shard, TestModel.OUTER_LIST_PATH);
 392         assertNotNull(TestModel.OUTER_LIST_QNAME.getLocalName() + " not found", outerList);
 393         assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " value is not Iterable",
 394                 outerList.getValue() instanceof Iterable);
 395         final Object entry = ((Iterable<Object>)outerList.getValue()).iterator().next();
 396         assertTrue(TestModel.OUTER_LIST_QNAME.getLocalName() + " entry is not MapEntryNode",
 397                 entry instanceof MapEntryNode);
 398         final MapEntryNode mapEntry = (MapEntryNode)entry;
 399         final Optional<DataContainerChild<? extends PathArgument, ?>> idLeaf =
 400                 mapEntry.getChild(new YangInstanceIdentifier.NodeIdentifier(TestModel.ID_QNAME));
 401         assertTrue("Missing leaf " + TestModel.ID_QNAME.getLocalName(), idLeaf.isPresent());
 402         assertEquals(TestModel.ID_QNAME.getLocalName() + " value", expIDValue, idLeaf.get().getValue());
 403     }
 404
 405     public static DataTreeCandidateTip mockCandidate(final String name) {
 406         final DataTreeCandidateTip mockCandidate = mock(DataTreeCandidateTip.class, name);
 407         final DataTreeCandidateNode mockCandidateNode = mock(DataTreeCandidateNode.class, name + "-node");
 408         doReturn(ModificationType.WRITE).when(mockCandidateNode).getModificationType();
 409         doReturn(Optional.of(ImmutableNodes.containerNode(CarsModel.CARS_QNAME)))
 410                 .when(mockCandidateNode).getDataAfter();
 411         doReturn(CarsModel.BASE_PATH).when(mockCandidate).getRootPath();
 412         doReturn(mockCandidateNode).when(mockCandidate).getRootNode();
 413         return mockCandidate;
 414     }
 415
 416     static DataTreeCandidateTip mockUnmodifiedCandidate(final String name) {
 417         final DataTreeCandidateTip mockCandidate = mock(DataTreeCandidateTip.class, name);
 418         final DataTreeCandidateNode mockCandidateNode = mock(DataTreeCandidateNode.class, name + "-node");
 419         doReturn(ModificationType.UNMODIFIED).when(mockCandidateNode).getModificationType();
 420         doReturn(YangInstanceIdentifier.empty()).when(mockCandidate).getRootPath();
 421         doReturn(mockCandidateNode).when(mockCandidate).getRootNode();
 422         return mockCandidate;
 423     }
 424
 425     static DataTreeCandidate commitTransaction(final DataTree store, final DataTreeModification modification)
 426             throws DataValidationFailedException {
 427         modification.ready();
 428         store.validate(modification);
 429         final DataTreeCandidate candidate = store.prepare(modification);
 430         store.commit(candidate);
 431         return candidate;
 432     }
 433
 434     @SuppressWarnings("serial")
 435     public static final class DelegatingShardCreator implements Creator<Shard> {
 436         private final Creator<Shard> delegate;
 437
 438         DelegatingShardCreator(final Creator<Shard> delegate) {
 439             this.delegate = delegate;
 440         }
 441
 442         @Override
 443         public Shard create() throws Exception {
 444             return delegate.create();
 445         }
 446     }
 447
 448     public static class CapturingShardDataTreeCohort extends ShardDataTreeCohort {
 449         private volatile ShardDataTreeCohort delegate;
 450         private FutureCallback<Void> canCommit;
 451         private FutureCallback<DataTreeCandidate> preCommit;
 452         private FutureCallback<UnsignedLong> commit;
 453
 454         public void setDelegate(final ShardDataTreeCohort delegate) {
 455             this.delegate = delegate;
 456         }
 457
 458         public FutureCallback<Void> getCanCommit() {
 459             assertNotNull("canCommit was not invoked", canCommit);
 460             return canCommit;
 461         }
 462
 463         public FutureCallback<DataTreeCandidate> getPreCommit() {
 464             assertNotNull("preCommit was not invoked", preCommit);
 465             return preCommit;
 466         }
 467
 468         public FutureCallback<UnsignedLong> getCommit() {
 469             assertNotNull("commit was not invoked", commit);
 470             return commit;
 471         }
 472
 473         @Override
 474         public TransactionIdentifier getIdentifier() {
 475             return delegate.getIdentifier();
 476         }
 477
 478         @Override
 479         DataTreeCandidateTip getCandidate() {
 480             return delegate.getCandidate();
 481         }
 482
 483         @Override
 484         DataTreeModification getDataTreeModification() {
 485             return delegate.getDataTreeModification();
 486         }
 487
 488         @Override
 489         public void canCommit(final FutureCallback<Void> callback) {
 490             canCommit = mockFutureCallback(callback);
 491             delegate.canCommit(canCommit);
 492         }
 493
 494         @Override
 495         public void preCommit(final FutureCallback<DataTreeCandidate> callback) {
 496             preCommit = mockFutureCallback(callback);
 497             delegate.preCommit(preCommit);
 498         }
 499
 500         @Override
 501         public void commit(final FutureCallback<UnsignedLong> callback) {
 502             commit = mockFutureCallback(callback);
 503             delegate.commit(commit);
 504         }
 505
 506         @SuppressWarnings("unchecked")
 507         private static <T> FutureCallback<T> mockFutureCallback(final FutureCallback<T> actual) {
 508             FutureCallback<T> mock = mock(FutureCallback.class);
 509             doAnswer(invocation -> {
 510                 actual.onFailure(invocation.getArgument(0));
 511                 return null;
 512             }).when(mock).onFailure(any(Throwable.class));
 513
 514             doAnswer(invocation -> {
 515                 actual.onSuccess(invocation.getArgument(0));
 516                 return null;
 517             }).when(mock).onSuccess((T) nullable(Object.class));
 518
 519             return mock;
 520         }
 521
 522         @Override
 523         public void abort(final FutureCallback<Void> callback) {
 524             delegate.abort(callback);
 525         }
 526
 527         @Override
 528         public boolean isFailed() {
 529             return delegate.isFailed();
 530         }
 531
 532         @Override
 533         public State getState() {
 534             return delegate.getState();
 535         }
 536
 537         @Override
 538         Optional<SortedSet<String>> getParticipatingShardNames() {
 539             return delegate.getParticipatingShardNames();
 540         }
 541     }
 542 }