opendaylight/md-sal/sal-akka-raft/src/test/java/org/opendaylight/controller/cluster/raft/RaftActorTest.java

   1 /*
   2  * Copyright (c) 2014, 2015 Cisco 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
   9 package org.opendaylight.controller.cluster.raft;
  10
  11 import static org.junit.Assert.assertEquals;
  12 import static org.junit.Assert.assertNotNull;
  13 import static org.junit.Assert.assertNull;
  14 import static org.junit.Assert.assertTrue;
  15 import static org.mockito.Matchers.any;
  16 import static org.mockito.Matchers.anyObject;
  17 import static org.mockito.Matchers.eq;
  18 import static org.mockito.Matchers.same;
  19 import static org.mockito.Mockito.doReturn;
  20 import static org.mockito.Mockito.mock;
  21 import static org.mockito.Mockito.times;
  22 import static org.mockito.Mockito.verify;
  23 import akka.actor.ActorRef;
  24 import akka.actor.PoisonPill;
  25 import akka.actor.Props;
  26 import akka.actor.Terminated;
  27 import akka.japi.Procedure;
  28 import akka.persistence.SaveSnapshotFailure;
  29 import akka.persistence.SaveSnapshotSuccess;
  30 import akka.persistence.SnapshotMetadata;
  31 import akka.persistence.SnapshotOffer;
  32 import akka.testkit.JavaTestKit;
  33 import akka.testkit.TestActorRef;
  34 import com.google.common.base.Optional;
  35 import com.google.common.collect.ImmutableMap;
  36 import com.google.common.util.concurrent.Uninterruptibles;
  37 import com.google.protobuf.ByteString;
  38 import java.io.ByteArrayOutputStream;
  39 import java.io.ObjectOutputStream;
  40 import java.util.ArrayList;
  41 import java.util.Arrays;
  42 import java.util.Collections;
  43 import java.util.HashMap;
  44 import java.util.List;
  45 import java.util.Map;
  46 import java.util.concurrent.TimeUnit;
  47 import org.junit.After;
  48 import org.junit.Before;
  49 import org.junit.Test;
  50 import org.opendaylight.controller.cluster.DataPersistenceProvider;
  51 import org.opendaylight.controller.cluster.NonPersistentDataProvider;
  52 import org.opendaylight.controller.cluster.notifications.LeaderStateChanged;
  53 import org.opendaylight.controller.cluster.notifications.RoleChanged;
  54 import org.opendaylight.controller.cluster.raft.base.messages.ApplyJournalEntries;
  55 import org.opendaylight.controller.cluster.raft.base.messages.ApplyLogEntries;
  56 import org.opendaylight.controller.cluster.raft.base.messages.ApplySnapshot;
  57 import org.opendaylight.controller.cluster.raft.base.messages.ApplyState;
  58 import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshot;
  59 import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshotReply;
  60 import org.opendaylight.controller.cluster.raft.base.messages.DeleteEntries;
  61 import org.opendaylight.controller.cluster.raft.base.messages.SendHeartBeat;
  62 import org.opendaylight.controller.cluster.raft.base.messages.UpdateElectionTerm;
  63 import org.opendaylight.controller.cluster.raft.behaviors.Follower;
  64 import org.opendaylight.controller.cluster.raft.behaviors.Leader;
  65 import org.opendaylight.controller.cluster.raft.behaviors.RaftActorBehavior;
  66 import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
  67 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
  68 import org.opendaylight.controller.cluster.raft.utils.InMemoryJournal;
  69 import org.opendaylight.controller.cluster.raft.utils.InMemorySnapshotStore;
  70 import org.opendaylight.controller.cluster.raft.utils.MessageCollectorActor;
  71 import org.slf4j.Logger;
  72 import org.slf4j.LoggerFactory;
  73 import scala.concurrent.duration.FiniteDuration;
  74
  75 public class RaftActorTest extends AbstractActorTest {
  76
  77     static final Logger TEST_LOG = LoggerFactory.getLogger(RaftActorTest.class);
  78
  79     private TestActorFactory factory;
  80
  81     @Before
  82     public void setUp(){
  83         factory = new TestActorFactory(getSystem());
  84     }
  85
  86     @After
  87     public void tearDown() throws Exception {
  88         factory.close();
  89         InMemoryJournal.clear();
  90         InMemorySnapshotStore.clear();
  91     }
  92
  93     @Test
  94     public void testConstruction() {
  95         new RaftActorTestKit(getSystem(), "testConstruction").waitUntilLeader();
  96     }
  97
  98     @Test
  99     public void testFindLeaderWhenLeaderIsSelf(){
 100         RaftActorTestKit kit = new RaftActorTestKit(getSystem(), "testFindLeader");
 101         kit.waitUntilLeader();
 102     }
 103
 104     @Test
 105     public void testRaftActorRecoveryWithPersistenceEnabled() throws Exception {
 106         TEST_LOG.info("testRaftActorRecoveryWithPersistenceEnabled starting");
 107
 108         new JavaTestKit(getSystem()) {{
 109             String persistenceId = factory.generateActorId("follower-");
 110
 111             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 112
 113             // Set the heartbeat interval high to essentially disable election otherwise the test
 114             // may fail if the actor is switched to Leader and the commitIndex is set to the last
 115             // log entry.
 116             config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 117
 118             ImmutableMap<String, String> peerAddresses = ImmutableMap.<String, String>builder().put("member1", "address").build();
 119             ActorRef followerActor = factory.createActor(MockRaftActor.props(persistenceId,
 120                     peerAddresses, Optional.<ConfigParams>of(config)), persistenceId);
 121
 122             watch(followerActor);
 123
 124             List<ReplicatedLogEntry> snapshotUnappliedEntries = new ArrayList<>();
 125             ReplicatedLogEntry entry1 = new MockRaftActorContext.MockReplicatedLogEntry(1, 4,
 126                     new MockRaftActorContext.MockPayload("E"));
 127             snapshotUnappliedEntries.add(entry1);
 128
 129             int lastAppliedDuringSnapshotCapture = 3;
 130             int lastIndexDuringSnapshotCapture = 4;
 131
 132             // 4 messages as part of snapshot, which are applied to state
 133             ByteString snapshotBytes = fromObject(Arrays.asList(
 134                     new MockRaftActorContext.MockPayload("A"),
 135                     new MockRaftActorContext.MockPayload("B"),
 136                     new MockRaftActorContext.MockPayload("C"),
 137                     new MockRaftActorContext.MockPayload("D")));
 138
 139             Snapshot snapshot = Snapshot.create(snapshotBytes.toByteArray(),
 140                     snapshotUnappliedEntries, lastIndexDuringSnapshotCapture, 1,
 141                     lastAppliedDuringSnapshotCapture, 1);
 142             InMemorySnapshotStore.addSnapshot(persistenceId, snapshot);
 143
 144             // add more entries after snapshot is taken
 145             List<ReplicatedLogEntry> entries = new ArrayList<>();
 146             ReplicatedLogEntry entry2 = new MockRaftActorContext.MockReplicatedLogEntry(1, 5,
 147                     new MockRaftActorContext.MockPayload("F", 2));
 148             ReplicatedLogEntry entry3 = new MockRaftActorContext.MockReplicatedLogEntry(1, 6,
 149                     new MockRaftActorContext.MockPayload("G", 3));
 150             ReplicatedLogEntry entry4 = new MockRaftActorContext.MockReplicatedLogEntry(1, 7,
 151                     new MockRaftActorContext.MockPayload("H", 4));
 152             entries.add(entry2);
 153             entries.add(entry3);
 154             entries.add(entry4);
 155
 156             int lastAppliedToState = 5;
 157             int lastIndex = 7;
 158
 159             InMemoryJournal.addEntry(persistenceId, 5, entry2);
 160             // 2 entries are applied to state besides the 4 entries in snapshot
 161             InMemoryJournal.addEntry(persistenceId, 6, new ApplyJournalEntries(lastAppliedToState));
 162             InMemoryJournal.addEntry(persistenceId, 7, entry3);
 163             InMemoryJournal.addEntry(persistenceId, 8, entry4);
 164
 165             // kill the actor
 166             followerActor.tell(PoisonPill.getInstance(), null);
 167             expectMsgClass(duration("5 seconds"), Terminated.class);
 168
 169             unwatch(followerActor);
 170
 171             //reinstate the actor
 172             TestActorRef<MockRaftActor> ref = factory.createTestActor(
 173                     MockRaftActor.props(persistenceId, peerAddresses, Optional.<ConfigParams>of(config)));
 174
 175             MockRaftActor mockRaftActor = ref.underlyingActor();
 176
 177             mockRaftActor.waitForRecoveryComplete();
 178
 179             RaftActorContext context = mockRaftActor.getRaftActorContext();
 180             assertEquals("Journal log size", snapshotUnappliedEntries.size() + entries.size(),
 181                     context.getReplicatedLog().size());
 182             assertEquals("Journal data size", 10, context.getReplicatedLog().dataSize());
 183             assertEquals("Last index", lastIndex, context.getReplicatedLog().lastIndex());
 184             assertEquals("Last applied", lastAppliedToState, context.getLastApplied());
 185             assertEquals("Commit index", lastAppliedToState, context.getCommitIndex());
 186             assertEquals("Recovered state size", 6, mockRaftActor.getState().size());
 187
 188             mockRaftActor.waitForInitializeBehaviorComplete();
 189
 190             assertEquals("getRaftState", RaftState.Follower, mockRaftActor.getRaftState());
 191         }};
 192
 193         TEST_LOG.info("testRaftActorRecoveryWithPersistenceEnabled ending");
 194     }
 195
 196     @Test
 197     public void testRaftActorRecoveryWithPersistenceDisabled() throws Exception {
 198         new JavaTestKit(getSystem()) {{
 199             String persistenceId = factory.generateActorId("follower-");
 200
 201             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 202
 203             config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 204
 205             TestActorRef<MockRaftActor> ref = factory.createTestActor(MockRaftActor.props(persistenceId,
 206                     ImmutableMap.<String, String>builder().put("member1", "address").build(),
 207                     Optional.<ConfigParams>of(config), new NonPersistentDataProvider()), persistenceId);
 208
 209             MockRaftActor mockRaftActor = ref.underlyingActor();
 210
 211             mockRaftActor.waitForRecoveryComplete();
 212
 213             mockRaftActor.waitForInitializeBehaviorComplete();
 214
 215             assertEquals("getRaftState", RaftState.Follower, mockRaftActor.getRaftState());
 216         }};
 217     }
 218
 219     @Test
 220     public void testRaftActorForwardsToRaftActorRecoverySupport() {
 221         String persistenceId = factory.generateActorId("leader-");
 222
 223         DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 224
 225         config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 226
 227         TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
 228                 Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config)), persistenceId);
 229
 230         MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
 231
 232         // Wait for akka's recovery to complete so it doesn't interfere.
 233         mockRaftActor.waitForRecoveryComplete();
 234
 235         RaftActorRecoverySupport mockSupport = mock(RaftActorRecoverySupport.class);
 236         mockRaftActor.setRaftActorRecoverySupport(mockSupport );
 237
 238         Snapshot snapshot = Snapshot.create(new byte[]{1}, Collections.<ReplicatedLogEntry>emptyList(), 3, 1, 3, 1);
 239         SnapshotOffer snapshotOffer = new SnapshotOffer(new SnapshotMetadata("test", 6, 12345), snapshot);
 240         mockRaftActor.handleRecover(snapshotOffer);
 241
 242         MockRaftActorContext.MockReplicatedLogEntry logEntry = new MockRaftActorContext.MockReplicatedLogEntry(1,
 243                 1, new MockRaftActorContext.MockPayload("1", 5));
 244         mockRaftActor.handleRecover(logEntry);
 245
 246         ApplyJournalEntries applyJournalEntries = new ApplyJournalEntries(2);
 247         mockRaftActor.handleRecover(applyJournalEntries);
 248
 249         ApplyLogEntries applyLogEntries = new ApplyLogEntries(0);
 250         mockRaftActor.handleRecover(applyLogEntries);
 251
 252         DeleteEntries deleteEntries = new DeleteEntries(1);
 253         mockRaftActor.handleRecover(deleteEntries);
 254
 255         org.opendaylight.controller.cluster.raft.RaftActor.DeleteEntries deprecatedDeleteEntries =
 256                 new org.opendaylight.controller.cluster.raft.RaftActor.DeleteEntries(1);
 257         mockRaftActor.handleRecover(deprecatedDeleteEntries);
 258
 259         UpdateElectionTerm updateElectionTerm = new UpdateElectionTerm(5, "member2");
 260         mockRaftActor.handleRecover(updateElectionTerm);
 261
 262         org.opendaylight.controller.cluster.raft.RaftActor.UpdateElectionTerm deprecatedUpdateElectionTerm =
 263                 new org.opendaylight.controller.cluster.raft.RaftActor.UpdateElectionTerm(6, "member3");
 264         mockRaftActor.handleRecover(deprecatedUpdateElectionTerm);
 265
 266         verify(mockSupport).handleRecoveryMessage(same(snapshotOffer));
 267         verify(mockSupport).handleRecoveryMessage(same(logEntry));
 268         verify(mockSupport).handleRecoveryMessage(same(applyJournalEntries));
 269         verify(mockSupport).handleRecoveryMessage(same(applyLogEntries));
 270         verify(mockSupport).handleRecoveryMessage(same(deleteEntries));
 271         verify(mockSupport).handleRecoveryMessage(same(deprecatedDeleteEntries));
 272         verify(mockSupport).handleRecoveryMessage(same(updateElectionTerm));
 273         verify(mockSupport).handleRecoveryMessage(same(deprecatedUpdateElectionTerm));
 274     }
 275
 276     @Test
 277     public void testRaftActorForwardsToRaftActorSnapshotMessageSupport() {
 278         String persistenceId = factory.generateActorId("leader-");
 279
 280         DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 281
 282         config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 283
 284         RaftActorSnapshotMessageSupport mockSupport = mock(RaftActorSnapshotMessageSupport.class);
 285
 286         TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
 287                 Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), mockSupport), persistenceId);
 288
 289         MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
 290
 291         // Wait for akka's recovery to complete so it doesn't interfere.
 292         mockRaftActor.waitForRecoveryComplete();
 293
 294         ApplySnapshot applySnapshot = new ApplySnapshot(mock(Snapshot.class));
 295         doReturn(true).when(mockSupport).handleSnapshotMessage(same(applySnapshot));
 296         mockRaftActor.handleCommand(applySnapshot);
 297
 298         CaptureSnapshot captureSnapshot = new CaptureSnapshot(1, 1, 1, 1, 0, 1, null);
 299         doReturn(true).when(mockSupport).handleSnapshotMessage(same(captureSnapshot));
 300         mockRaftActor.handleCommand(captureSnapshot);
 301
 302         CaptureSnapshotReply captureSnapshotReply = new CaptureSnapshotReply(new byte[0]);
 303         doReturn(true).when(mockSupport).handleSnapshotMessage(same(captureSnapshotReply));
 304         mockRaftActor.handleCommand(captureSnapshotReply);
 305
 306         SaveSnapshotSuccess saveSnapshotSuccess = new SaveSnapshotSuccess(mock(SnapshotMetadata.class));
 307         doReturn(true).when(mockSupport).handleSnapshotMessage(same(saveSnapshotSuccess));
 308         mockRaftActor.handleCommand(saveSnapshotSuccess);
 309
 310         SaveSnapshotFailure saveSnapshotFailure = new SaveSnapshotFailure(mock(SnapshotMetadata.class), new Throwable());
 311         doReturn(true).when(mockSupport).handleSnapshotMessage(same(saveSnapshotFailure));
 312         mockRaftActor.handleCommand(saveSnapshotFailure);
 313
 314         doReturn(true).when(mockSupport).handleSnapshotMessage(same(RaftActorSnapshotMessageSupport.COMMIT_SNAPSHOT));
 315         mockRaftActor.handleCommand(RaftActorSnapshotMessageSupport.COMMIT_SNAPSHOT);
 316
 317         verify(mockSupport).handleSnapshotMessage(same(applySnapshot));
 318         verify(mockSupport).handleSnapshotMessage(same(captureSnapshot));
 319         verify(mockSupport).handleSnapshotMessage(same(captureSnapshotReply));
 320         verify(mockSupport).handleSnapshotMessage(same(saveSnapshotSuccess));
 321         verify(mockSupport).handleSnapshotMessage(same(saveSnapshotFailure));
 322         verify(mockSupport).handleSnapshotMessage(same(RaftActorSnapshotMessageSupport.COMMIT_SNAPSHOT));
 323     }
 324
 325     @Test
 326     public void testApplyJournalEntriesCallsDataPersistence() throws Exception {
 327         new JavaTestKit(getSystem()) {
 328             {
 329                 String persistenceId = factory.generateActorId("leader-");
 330
 331                 DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 332
 333                 config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 334
 335                 DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
 336
 337                 TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
 338                         Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 339
 340                 MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
 341
 342                 mockRaftActor.waitForInitializeBehaviorComplete();
 343
 344                 mockRaftActor.waitUntilLeader();
 345
 346                 mockRaftActor.onReceiveCommand(new ApplyJournalEntries(10));
 347
 348                 verify(dataPersistenceProvider, times(2)).persist(anyObject(), any(Procedure.class));
 349
 350             }
 351
 352         };
 353     }
 354
 355     @Test
 356     public void testApplyState() throws Exception {
 357
 358         new JavaTestKit(getSystem()) {
 359             {
 360                 String persistenceId = factory.generateActorId("leader-");
 361
 362                 DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 363
 364                 config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 365
 366                 DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
 367
 368                 TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
 369                         Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 370
 371                 MockRaftActor mockRaftActor = mockActorRef.underlyingActor();
 372
 373                 mockRaftActor.waitForInitializeBehaviorComplete();
 374
 375                 ReplicatedLogEntry entry = new MockRaftActorContext.MockReplicatedLogEntry(1, 5,
 376                         new MockRaftActorContext.MockPayload("F"));
 377
 378                 mockRaftActor.onReceiveCommand(new ApplyState(mockActorRef, "apply-state", entry));
 379
 380                 verify(mockRaftActor.actorDelegate).applyState(eq(mockActorRef), eq("apply-state"), anyObject());
 381
 382             }
 383         };
 384     }
 385
 386     @Test
 387     public void testRaftRoleChangeNotifierWhenRaftActorHasNoPeers() throws Exception {
 388         new JavaTestKit(getSystem()) {{
 389             TestActorRef<MessageCollectorActor> notifierActor = factory.createTestActor(
 390                     Props.create(MessageCollectorActor.class));
 391             MessageCollectorActor.waitUntilReady(notifierActor);
 392
 393             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 394             long heartBeatInterval = 100;
 395             config.setHeartBeatInterval(FiniteDuration.create(heartBeatInterval, TimeUnit.MILLISECONDS));
 396             config.setElectionTimeoutFactor(20);
 397
 398             String persistenceId = factory.generateActorId("notifier-");
 399
 400             TestActorRef<MockRaftActor> raftActorRef = factory.createTestActor(MockRaftActor.props(persistenceId,
 401                     Collections.<String, String>emptyMap(), Optional.<ConfigParams>of(config), notifierActor,
 402                     new NonPersistentDataProvider()), persistenceId);
 403
 404             List<RoleChanged> matches =  MessageCollectorActor.expectMatching(notifierActor, RoleChanged.class, 3);
 405
 406
 407             // check if the notifier got a role change from null to Follower
 408             RoleChanged raftRoleChanged = matches.get(0);
 409             assertEquals(persistenceId, raftRoleChanged.getMemberId());
 410             assertNull(raftRoleChanged.getOldRole());
 411             assertEquals(RaftState.Follower.name(), raftRoleChanged.getNewRole());
 412
 413             // check if the notifier got a role change from Follower to Candidate
 414             raftRoleChanged = matches.get(1);
 415             assertEquals(persistenceId, raftRoleChanged.getMemberId());
 416             assertEquals(RaftState.Follower.name(), raftRoleChanged.getOldRole());
 417             assertEquals(RaftState.Candidate.name(), raftRoleChanged.getNewRole());
 418
 419             // check if the notifier got a role change from Candidate to Leader
 420             raftRoleChanged = matches.get(2);
 421             assertEquals(persistenceId, raftRoleChanged.getMemberId());
 422             assertEquals(RaftState.Candidate.name(), raftRoleChanged.getOldRole());
 423             assertEquals(RaftState.Leader.name(), raftRoleChanged.getNewRole());
 424
 425             LeaderStateChanged leaderStateChange = MessageCollectorActor.expectFirstMatching(
 426                     notifierActor, LeaderStateChanged.class);
 427
 428             assertEquals(raftRoleChanged.getMemberId(), leaderStateChange.getLeaderId());
 429             assertEquals(MockRaftActor.PAYLOAD_VERSION, leaderStateChange.getLeaderPayloadVersion());
 430
 431             notifierActor.underlyingActor().clear();
 432
 433             MockRaftActor raftActor = raftActorRef.underlyingActor();
 434             final String newLeaderId = "new-leader";
 435             final short newLeaderVersion = 6;
 436             Follower follower = new Follower(raftActor.getRaftActorContext()) {
 437                 @Override
 438                 public RaftActorBehavior handleMessage(ActorRef sender, Object message) {
 439                     leaderId = newLeaderId;
 440                     setLeaderPayloadVersion(newLeaderVersion);
 441                     return this;
 442                 }
 443             };
 444
 445             raftActor.changeCurrentBehavior(follower);
 446
 447             leaderStateChange = MessageCollectorActor.expectFirstMatching(notifierActor, LeaderStateChanged.class);
 448             assertEquals(persistenceId, leaderStateChange.getMemberId());
 449             assertEquals(null, leaderStateChange.getLeaderId());
 450
 451             raftRoleChanged = MessageCollectorActor.expectFirstMatching(notifierActor, RoleChanged.class);
 452             assertEquals(RaftState.Leader.name(), raftRoleChanged.getOldRole());
 453             assertEquals(RaftState.Follower.name(), raftRoleChanged.getNewRole());
 454
 455             notifierActor.underlyingActor().clear();
 456
 457             raftActor.handleCommand("any");
 458
 459             leaderStateChange = MessageCollectorActor.expectFirstMatching(notifierActor, LeaderStateChanged.class);
 460             assertEquals(persistenceId, leaderStateChange.getMemberId());
 461             assertEquals(newLeaderId, leaderStateChange.getLeaderId());
 462             assertEquals(newLeaderVersion, leaderStateChange.getLeaderPayloadVersion());
 463
 464             notifierActor.underlyingActor().clear();
 465
 466             raftActor.handleCommand("any");
 467
 468             Uninterruptibles.sleepUninterruptibly(505, TimeUnit.MILLISECONDS);
 469             leaderStateChange = MessageCollectorActor.getFirstMatching(notifierActor, LeaderStateChanged.class);
 470             assertNull(leaderStateChange);
 471         }};
 472     }
 473
 474     @Test
 475     public void testRaftRoleChangeNotifierWhenRaftActorHasPeers() throws Exception {
 476         new JavaTestKit(getSystem()) {{
 477             ActorRef notifierActor = factory.createActor(Props.create(MessageCollectorActor.class));
 478             MessageCollectorActor.waitUntilReady(notifierActor);
 479
 480             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 481             long heartBeatInterval = 100;
 482             config.setHeartBeatInterval(FiniteDuration.create(heartBeatInterval, TimeUnit.MILLISECONDS));
 483             config.setElectionTimeoutFactor(1);
 484
 485             String persistenceId = factory.generateActorId("notifier-");
 486
 487             factory.createActor(MockRaftActor.props(persistenceId,
 488                     ImmutableMap.of("leader", "fake/path"), Optional.<ConfigParams>of(config), notifierActor), persistenceId);
 489
 490             List<RoleChanged> matches =  null;
 491             for(int i = 0; i < 5000 / heartBeatInterval; i++) {
 492                 matches = MessageCollectorActor.getAllMatching(notifierActor, RoleChanged.class);
 493                 assertNotNull(matches);
 494                 if(matches.size() == 3) {
 495                     break;
 496                 }
 497                 Uninterruptibles.sleepUninterruptibly(heartBeatInterval, TimeUnit.MILLISECONDS);
 498             }
 499
 500             assertNotNull(matches);
 501             assertEquals(2, matches.size());
 502
 503             // check if the notifier got a role change from null to Follower
 504             RoleChanged raftRoleChanged = matches.get(0);
 505             assertEquals(persistenceId, raftRoleChanged.getMemberId());
 506             assertNull(raftRoleChanged.getOldRole());
 507             assertEquals(RaftState.Follower.name(), raftRoleChanged.getNewRole());
 508
 509             // check if the notifier got a role change from Follower to Candidate
 510             raftRoleChanged = matches.get(1);
 511             assertEquals(persistenceId, raftRoleChanged.getMemberId());
 512             assertEquals(RaftState.Follower.name(), raftRoleChanged.getOldRole());
 513             assertEquals(RaftState.Candidate.name(), raftRoleChanged.getNewRole());
 514
 515         }};
 516     }
 517
 518     @Test
 519     public void testFakeSnapshotsForLeaderWithInRealSnapshots() throws Exception {
 520         new JavaTestKit(getSystem()) {
 521             {
 522                 String persistenceId = factory.generateActorId("leader-");
 523                 String follower1Id = factory.generateActorId("follower-");
 524
 525                 ActorRef followerActor1 =
 526                         factory.createActor(Props.create(MessageCollectorActor.class));
 527
 528                 DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 529                 config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 530                 config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
 531
 532                 DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
 533
 534                 Map<String, String> peerAddresses = new HashMap<>();
 535                 peerAddresses.put(follower1Id, followerActor1.path().toString());
 536
 537                 TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
 538                         MockRaftActor.props(persistenceId, peerAddresses,
 539                                 Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 540
 541                 MockRaftActor leaderActor = mockActorRef.underlyingActor();
 542
 543                 leaderActor.getRaftActorContext().setCommitIndex(4);
 544                 leaderActor.getRaftActorContext().setLastApplied(4);
 545                 leaderActor.getRaftActorContext().getTermInformation().update(1, persistenceId);
 546
 547                 leaderActor.waitForInitializeBehaviorComplete();
 548
 549                 // create 8 entries in the log - 0 to 4 are applied and will get picked up as part of the capture snapshot
 550
 551                 Leader leader = new Leader(leaderActor.getRaftActorContext());
 552                 leaderActor.setCurrentBehavior(leader);
 553                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 554
 555                 MockRaftActorContext.MockReplicatedLogBuilder logBuilder = new MockRaftActorContext.MockReplicatedLogBuilder();
 556                 leaderActor.getRaftActorContext().setReplicatedLog(logBuilder.createEntries(0, 8, 1).build());
 557
 558                 assertEquals(8, leaderActor.getReplicatedLog().size());
 559
 560                 leaderActor.getRaftActorContext().getSnapshotManager()
 561                         .capture(new MockRaftActorContext.MockReplicatedLogEntry(1, 6,
 562                                 new MockRaftActorContext.MockPayload("x")), 4);
 563
 564                 verify(leaderActor.snapshotCohortDelegate).createSnapshot(any(ActorRef.class));
 565
 566                 assertEquals(8, leaderActor.getReplicatedLog().size());
 567
 568                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 569                 //fake snapshot on index 5
 570                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 5, 1, (short)0));
 571
 572                 assertEquals(8, leaderActor.getReplicatedLog().size());
 573
 574                 //fake snapshot on index 6
 575                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 576                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 6, 1, (short)0));
 577                 assertEquals(8, leaderActor.getReplicatedLog().size());
 578
 579                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 580
 581                 assertEquals(8, leaderActor.getReplicatedLog().size());
 582
 583                 ByteString snapshotBytes = fromObject(Arrays.asList(
 584                         new MockRaftActorContext.MockPayload("foo-0"),
 585                         new MockRaftActorContext.MockPayload("foo-1"),
 586                         new MockRaftActorContext.MockPayload("foo-2"),
 587                         new MockRaftActorContext.MockPayload("foo-3"),
 588                         new MockRaftActorContext.MockPayload("foo-4")));
 589
 590                 leaderActor.getRaftActorContext().getSnapshotManager().persist(snapshotBytes.toByteArray(),
 591                         leader, Runtime.getRuntime().totalMemory());
 592
 593                 assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
 594
 595                 // The commit is needed to complete the snapshot creation process
 596                 leaderActor.getRaftActorContext().getSnapshotManager().commit(-1, leader);
 597
 598                 // capture snapshot reply should remove the snapshotted entries only
 599                 assertEquals(3, leaderActor.getReplicatedLog().size());
 600                 assertEquals(7, leaderActor.getReplicatedLog().lastIndex());
 601
 602                 // add another non-replicated entry
 603                 leaderActor.getReplicatedLog().append(
 604                         new ReplicatedLogImplEntry(8, 1, new MockRaftActorContext.MockPayload("foo-8")));
 605
 606                 //fake snapshot on index 7, since lastApplied = 7 , we would keep the last applied
 607                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 7, 1, (short)0));
 608                 assertEquals(2, leaderActor.getReplicatedLog().size());
 609                 assertEquals(8, leaderActor.getReplicatedLog().lastIndex());
 610
 611             }
 612         };
 613     }
 614
 615     @Test
 616     public void testFakeSnapshotsForFollowerWithInRealSnapshots() throws Exception {
 617         new JavaTestKit(getSystem()) {
 618             {
 619                 String persistenceId = factory.generateActorId("follower-");
 620                 String leaderId = factory.generateActorId("leader-");
 621
 622
 623                 ActorRef leaderActor1 =
 624                         factory.createActor(Props.create(MessageCollectorActor.class));
 625
 626                 DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 627                 config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 628                 config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
 629
 630                 DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
 631
 632                 Map<String, String> peerAddresses = new HashMap<>();
 633                 peerAddresses.put(leaderId, leaderActor1.path().toString());
 634
 635                 TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
 636                         MockRaftActor.props(persistenceId, peerAddresses,
 637                                 Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 638
 639                 MockRaftActor followerActor = mockActorRef.underlyingActor();
 640                 followerActor.getRaftActorContext().setCommitIndex(4);
 641                 followerActor.getRaftActorContext().setLastApplied(4);
 642                 followerActor.getRaftActorContext().getTermInformation().update(1, persistenceId);
 643
 644                 followerActor.waitForInitializeBehaviorComplete();
 645
 646
 647                 Follower follower = new Follower(followerActor.getRaftActorContext());
 648                 followerActor.setCurrentBehavior(follower);
 649                 assertEquals(RaftState.Follower, followerActor.getCurrentBehavior().state());
 650
 651                 // create 6 entries in the log - 0 to 4 are applied and will get picked up as part of the capture snapshot
 652                 MockRaftActorContext.MockReplicatedLogBuilder logBuilder = new MockRaftActorContext.MockReplicatedLogBuilder();
 653                 followerActor.getRaftActorContext().setReplicatedLog(logBuilder.createEntries(0, 6, 1).build());
 654
 655                 // log has indices 0-5
 656                 assertEquals(6, followerActor.getReplicatedLog().size());
 657
 658                 //snapshot on 4
 659                 followerActor.getRaftActorContext().getSnapshotManager().capture(
 660                         new MockRaftActorContext.MockReplicatedLogEntry(1, 5,
 661                                 new MockRaftActorContext.MockPayload("D")), 4);
 662
 663                 verify(followerActor.snapshotCohortDelegate).createSnapshot(any(ActorRef.class));
 664
 665                 assertEquals(6, followerActor.getReplicatedLog().size());
 666
 667                 //fake snapshot on index 6
 668                 List<ReplicatedLogEntry> entries =
 669                         Arrays.asList(
 670                                 (ReplicatedLogEntry) new MockRaftActorContext.MockReplicatedLogEntry(1, 6,
 671                                         new MockRaftActorContext.MockPayload("foo-6"))
 672                         );
 673                 followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 5, 1, entries, 5, 5, (short)0));
 674                 assertEquals(7, followerActor.getReplicatedLog().size());
 675
 676                 //fake snapshot on index 7
 677                 assertEquals(RaftState.Follower, followerActor.getCurrentBehavior().state());
 678
 679                 entries =
 680                         Arrays.asList(
 681                                 (ReplicatedLogEntry) new MockRaftActorContext.MockReplicatedLogEntry(1, 7,
 682                                         new MockRaftActorContext.MockPayload("foo-7"))
 683                         );
 684                 followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 6, 1, entries, 6, 6, (short)0));
 685                 assertEquals(8, followerActor.getReplicatedLog().size());
 686
 687                 assertEquals(RaftState.Follower, followerActor.getCurrentBehavior().state());
 688
 689
 690                 ByteString snapshotBytes = fromObject(Arrays.asList(
 691                         new MockRaftActorContext.MockPayload("foo-0"),
 692                         new MockRaftActorContext.MockPayload("foo-1"),
 693                         new MockRaftActorContext.MockPayload("foo-2"),
 694                         new MockRaftActorContext.MockPayload("foo-3"),
 695                         new MockRaftActorContext.MockPayload("foo-4")));
 696                 followerActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
 697                 assertTrue(followerActor.getRaftActorContext().getSnapshotManager().isCapturing());
 698
 699                 // The commit is needed to complete the snapshot creation process
 700                 followerActor.getRaftActorContext().getSnapshotManager().commit(-1, follower);
 701
 702                 // capture snapshot reply should remove the snapshotted entries only till replicatedToAllIndex
 703                 assertEquals(3, followerActor.getReplicatedLog().size()); //indexes 5,6,7 left in the log
 704                 assertEquals(7, followerActor.getReplicatedLog().lastIndex());
 705
 706                 entries =
 707                         Arrays.asList(
 708                                 (ReplicatedLogEntry) new MockRaftActorContext.MockReplicatedLogEntry(1, 8,
 709                                         new MockRaftActorContext.MockPayload("foo-7"))
 710                         );
 711                 // send an additional entry 8 with leaderCommit = 7
 712                 followerActor.onReceiveCommand(new AppendEntries(1, leaderId, 7, 1, entries, 7, 7, (short)0));
 713
 714                 // 7 and 8, as lastapplied is 7
 715                 assertEquals(2, followerActor.getReplicatedLog().size());
 716
 717             }
 718         };
 719     }
 720
 721     @Test
 722     public void testFakeSnapshotsForLeaderWithInInitiateSnapshots() throws Exception {
 723         new JavaTestKit(getSystem()) {
 724             {
 725                 String persistenceId = factory.generateActorId("leader-");
 726                 String follower1Id = factory.generateActorId("follower-");
 727                 String follower2Id = factory.generateActorId("follower-");
 728
 729                 ActorRef followerActor1 =
 730                         factory.createActor(Props.create(MessageCollectorActor.class), follower1Id);
 731                 ActorRef followerActor2 =
 732                         factory.createActor(Props.create(MessageCollectorActor.class), follower2Id);
 733
 734                 DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 735                 config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 736                 config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
 737
 738                 DataPersistenceProvider dataPersistenceProvider = mock(DataPersistenceProvider.class);
 739
 740                 Map<String, String> peerAddresses = new HashMap<>();
 741                 peerAddresses.put(follower1Id, followerActor1.path().toString());
 742                 peerAddresses.put(follower2Id, followerActor2.path().toString());
 743
 744                 TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
 745                         MockRaftActor.props(persistenceId, peerAddresses,
 746                                 Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 747
 748                 MockRaftActor leaderActor = mockActorRef.underlyingActor();
 749                 leaderActor.getRaftActorContext().setCommitIndex(9);
 750                 leaderActor.getRaftActorContext().setLastApplied(9);
 751                 leaderActor.getRaftActorContext().getTermInformation().update(1, persistenceId);
 752
 753                 leaderActor.waitForInitializeBehaviorComplete();
 754
 755                 Leader leader = new Leader(leaderActor.getRaftActorContext());
 756                 leaderActor.setCurrentBehavior(leader);
 757                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 758
 759                 // create 5 entries in the log
 760                 MockRaftActorContext.MockReplicatedLogBuilder logBuilder = new MockRaftActorContext.MockReplicatedLogBuilder();
 761                 leaderActor.getRaftActorContext().setReplicatedLog(logBuilder.createEntries(5, 10, 1).build());
 762
 763                 //set the snapshot index to 4 , 0 to 4 are snapshotted
 764                 leaderActor.getRaftActorContext().getReplicatedLog().setSnapshotIndex(4);
 765                 //setting replicatedToAllIndex = 9, for the log to clear
 766                 leader.setReplicatedToAllIndex(9);
 767                 assertEquals(5, leaderActor.getReplicatedLog().size());
 768                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 769
 770                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower1Id, 1, true, 9, 1, (short)0));
 771                 assertEquals(5, leaderActor.getReplicatedLog().size());
 772                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 773
 774                 // set the 2nd follower nextIndex to 1 which has been snapshotted
 775                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 0, 1, (short)0));
 776                 assertEquals(5, leaderActor.getReplicatedLog().size());
 777                 assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 778
 779                 // simulate a real snapshot
 780                 leaderActor.onReceiveCommand(new SendHeartBeat());
 781                 assertEquals(5, leaderActor.getReplicatedLog().size());
 782                 assertEquals(String.format("expected to be Leader but was %s. Current Leader = %s ",
 783                         leaderActor.getCurrentBehavior().state(), leaderActor.getLeaderId())
 784                         , RaftState.Leader, leaderActor.getCurrentBehavior().state());
 785
 786
 787                 //reply from a slow follower does not initiate a fake snapshot
 788                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 9, 1, (short)0));
 789                 assertEquals("Fake snapshot should not happen when Initiate is in progress", 5, leaderActor.getReplicatedLog().size());
 790
 791                 ByteString snapshotBytes = fromObject(Arrays.asList(
 792                         new MockRaftActorContext.MockPayload("foo-0"),
 793                         new MockRaftActorContext.MockPayload("foo-1"),
 794                         new MockRaftActorContext.MockPayload("foo-2"),
 795                         new MockRaftActorContext.MockPayload("foo-3"),
 796                         new MockRaftActorContext.MockPayload("foo-4")));
 797                 leaderActor.onReceiveCommand(new CaptureSnapshotReply(snapshotBytes.toByteArray()));
 798                 assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
 799
 800                 assertEquals("Real snapshot didn't clear the log till replicatedToAllIndex", 0, leaderActor.getReplicatedLog().size());
 801
 802                 //reply from a slow follower after should not raise errors
 803                 leaderActor.onReceiveCommand(new AppendEntriesReply(follower2Id, 1, true, 5, 1, (short)0));
 804                 assertEquals(0, leaderActor.getReplicatedLog().size());
 805             }
 806         };
 807     }
 808
 809     @Test
 810     public void testRealSnapshotWhenReplicatedToAllIndexMinusOne() throws Exception {
 811         new JavaTestKit(getSystem()) {{
 812             String persistenceId = factory.generateActorId("leader-");
 813             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 814             config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 815             config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
 816             config.setSnapshotBatchCount(5);
 817
 818             DataPersistenceProvider dataPersistenceProvider = new NonPersistentDataProvider();
 819
 820             Map<String, String> peerAddresses = ImmutableMap.<String, String>builder().put("member1", "address").build();
 821
 822             TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
 823                     MockRaftActor.props(persistenceId, peerAddresses,
 824                             Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 825
 826             MockRaftActor leaderActor = mockActorRef.underlyingActor();
 827             leaderActor.getRaftActorContext().setCommitIndex(3);
 828             leaderActor.getRaftActorContext().setLastApplied(3);
 829             leaderActor.getRaftActorContext().getTermInformation().update(1, persistenceId);
 830
 831             leaderActor.waitForInitializeBehaviorComplete();
 832             for(int i=0;i< 4;i++) {
 833                 leaderActor.getReplicatedLog()
 834                         .append(new MockRaftActorContext.MockReplicatedLogEntry(1, i,
 835                                 new MockRaftActorContext.MockPayload("A")));
 836             }
 837
 838             Leader leader = new Leader(leaderActor.getRaftActorContext());
 839             leaderActor.setCurrentBehavior(leader);
 840             assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 841
 842             // Simulate an install snaphost to a follower.
 843             leaderActor.getRaftActorContext().getSnapshotManager().captureToInstall(
 844                     leaderActor.getReplicatedLog().last(), -1, "member1");
 845
 846             // Now send a CaptureSnapshotReply
 847             mockActorRef.tell(new CaptureSnapshotReply(fromObject("foo").toByteArray()), mockActorRef);
 848
 849             // Trimming log in this scenario is a no-op
 850             assertEquals(-1, leaderActor.getReplicatedLog().getSnapshotIndex());
 851             assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
 852             assertEquals(-1, leader.getReplicatedToAllIndex());
 853
 854         }};
 855     }
 856
 857     @Test
 858     public void testRealSnapshotWhenReplicatedToAllIndexNotInReplicatedLog() throws Exception {
 859         new JavaTestKit(getSystem()) {{
 860             String persistenceId = factory.generateActorId("leader-");
 861             DefaultConfigParamsImpl config = new DefaultConfigParamsImpl();
 862             config.setHeartBeatInterval(new FiniteDuration(1, TimeUnit.DAYS));
 863             config.setIsolatedLeaderCheckInterval(new FiniteDuration(1, TimeUnit.DAYS));
 864             config.setSnapshotBatchCount(5);
 865
 866             DataPersistenceProvider dataPersistenceProvider = new NonPersistentDataProvider();
 867
 868             Map<String, String> peerAddresses = ImmutableMap.<String, String>builder().put("member1", "address").build();
 869
 870             TestActorRef<MockRaftActor> mockActorRef = factory.createTestActor(
 871                     MockRaftActor.props(persistenceId, peerAddresses,
 872                             Optional.<ConfigParams>of(config), dataPersistenceProvider), persistenceId);
 873
 874             MockRaftActor leaderActor = mockActorRef.underlyingActor();
 875             leaderActor.getRaftActorContext().setCommitIndex(3);
 876             leaderActor.getRaftActorContext().setLastApplied(3);
 877             leaderActor.getRaftActorContext().getTermInformation().update(1, persistenceId);
 878             leaderActor.getReplicatedLog().setSnapshotIndex(3);
 879
 880             leaderActor.waitForInitializeBehaviorComplete();
 881             Leader leader = new Leader(leaderActor.getRaftActorContext());
 882             leaderActor.setCurrentBehavior(leader);
 883             leader.setReplicatedToAllIndex(3);
 884             assertEquals(RaftState.Leader, leaderActor.getCurrentBehavior().state());
 885
 886             // Persist another entry (this will cause a CaptureSnapshot to be triggered
 887             leaderActor.persistData(mockActorRef, "x", new MockRaftActorContext.MockPayload("duh"));
 888
 889             // Now send a CaptureSnapshotReply
 890             mockActorRef.tell(new CaptureSnapshotReply(fromObject("foo").toByteArray()), mockActorRef);
 891
 892             // Trimming log in this scenario is a no-op
 893             assertEquals(3, leaderActor.getReplicatedLog().getSnapshotIndex());
 894             assertTrue(leaderActor.getRaftActorContext().getSnapshotManager().isCapturing());
 895             assertEquals(3, leader.getReplicatedToAllIndex());
 896
 897         }};
 898     }
 899
 900     public static ByteString fromObject(Object snapshot) throws Exception {
 901         ByteArrayOutputStream b = null;
 902         ObjectOutputStream o = null;
 903         try {
 904             b = new ByteArrayOutputStream();
 905             o = new ObjectOutputStream(b);
 906             o.writeObject(snapshot);
 907             byte[] snapshotBytes = b.toByteArray();
 908             return ByteString.copyFrom(snapshotBytes);
 909         } finally {
 910             if (o != null) {
 911                 o.flush();
 912                 o.close();
 913             }
 914             if (b != null) {
 915                 b.close();
 916             }
 917         }
 918     }
 919
 920 }