@Test
  public void replicaFromInactiveToOfflineTest() throws Exception {
    MockClusterMap clusterMap = new MockClusterMap();
    ClusterMapConfig clusterMapConfig = new ClusterMapConfig(verifiableProperties);
    MockHelixParticipant.metricRegistry = new MetricRegistry();
    MockHelixParticipant mockHelixParticipant = new MockHelixParticipant(clusterMapConfig);
    Pair<StorageManager, ReplicationManager> managers =
        createStorageManagerAndReplicationManager(clusterMap, clusterMapConfig, mockHelixParticipant);
    StorageManager storageManager = managers.getFirst();
    MockReplicationManager replicationManager = (MockReplicationManager) managers.getSecond();
    // 1. test replica not found case
    try {
      mockHelixParticipant.onPartitionBecomeOfflineFromInactive("-1");
      fail("should fail because of invalid partition");
    } catch (StateTransitionException e) {
      assertEquals("Error code doesn't match", ReplicaNotFound, e.getErrorCode());
    }
    // 2. test store not started case
    PartitionId existingPartition = replicationManager.partitionToPartitionInfo.keySet().iterator().next();
    storageManager.shutdownBlobStore(existingPartition);
    try {
      mockHelixParticipant.onPartitionBecomeOfflineFromInactive(existingPartition.toPathString());
      fail("should fail because store is not started");
    } catch (StateTransitionException e) {
      assertEquals("Error code doesn't match", StoreNotStarted, e.getErrorCode());
    }
    storageManager.startBlobStore(existingPartition);
    // before testing success case, let's write a blob (size = 100) into local store and add a delete record for new blob
    Store localStore = storageManager.getStore(existingPartition);
    MockId id = new MockId(TestUtils.getRandomString(10), Utils.getRandomShort(TestUtils.RANDOM),
        Utils.getRandomShort(TestUtils.RANDOM));
    long crc = (new Random()).nextLong();
    long blobSize = 100;
    MessageInfo info =
        new MessageInfo(id, blobSize, false, false, Utils.Infinite_Time, crc, id.getAccountId(), id.getContainerId(),
            Utils.Infinite_Time);
    List<MessageInfo> infos = new ArrayList<>();
    List<ByteBuffer> buffers = new ArrayList<>();
    ByteBuffer buffer = ByteBuffer.wrap(TestUtils.getRandomBytes((int) blobSize));
    infos.add(info);
    buffers.add(buffer);
    localStore.put(new MockMessageWriteSet(infos, buffers));
    // delete the blob
    int deleteRecordSize = (int) (new DeleteMessageFormatInputStream(id, (short) 0, (short) 0, 0).getSize());
    MessageInfo deleteInfo =
        new MessageInfo(id, deleteRecordSize, id.getAccountId(), id.getContainerId(), time.milliseconds());
    localStore.delete(Collections.singletonList(deleteInfo));
    int sizeOfPutAndHeader = 100 + 18;
    int sizeOfWhole = sizeOfPutAndHeader + deleteRecordSize;
    // note that end offset of last PUT = 100 + 18 = 118, end offset of the store is sizeOfWhole
    // 3. test success case (create a new thread and trigger INACTIVE -> OFFLINE transition)
    ReplicaId localReplica = storageManager.getReplica(existingPartition.toPathString());
    // put a decommission-in-progress file into local store dir
    File decommissionFile = new File(localReplica.getReplicaPath(), "decommission_in_progress");
    assertTrue("Couldn't create decommission file in local store", decommissionFile.createNewFile());
    decommissionFile.deleteOnExit();
    assertNotSame("Before disconnection, the local store state shouldn't be OFFLINE", ReplicaState.OFFLINE,
        localStore.getCurrentState());
    mockHelixParticipant.registerPartitionStateChangeListener(StateModelListenerType.ReplicationManagerListener,
        replicationManager.replicationListener);
    CountDownLatch participantLatch = new CountDownLatch(1);
    replicationManager.listenerExecutionLatch = new CountDownLatch(1);
    Utils.newThread(() -> {
      mockHelixParticipant.onPartitionBecomeOfflineFromInactive(existingPartition.toPathString());
      participantLatch.countDown();
    }, false).start();
    assertTrue("Partition state change listener in ReplicationManager didn't get called within 1 sec",
        replicationManager.listenerExecutionLatch.await(1, TimeUnit.SECONDS));
    // the state of local store should be updated to OFFLINE
    assertEquals("Local store state is not expected", ReplicaState.OFFLINE, localStore.getCurrentState());
    // update replication lag between local and peer replicas
    List<RemoteReplicaInfo> remoteReplicaInfos =
        replicationManager.partitionToPartitionInfo.get(existingPartition).getRemoteReplicaInfos();
    ReplicaId peerReplica1 = remoteReplicaInfos.get(0).getReplicaId();
    ReplicaId peerReplica2 = remoteReplicaInfos.get(1).getReplicaId();
    // peer1 catches up with last PUT, peer2 catches up with end offset of local store. In this case, SyncUp is not complete
    replicationManager.updateTotalBytesReadByRemoteReplica(existingPartition,
        peerReplica1.getDataNodeId().getHostname(), peerReplica1.getReplicaPath(), sizeOfPutAndHeader);
    replicationManager.updateTotalBytesReadByRemoteReplica(existingPartition,
        peerReplica2.getDataNodeId().getHostname(), peerReplica2.getReplicaPath(), sizeOfWhole);
    assertFalse("Only one peer replica has fully caught up with end offset so sync-up should not complete",
        mockHelixParticipant.getReplicaSyncUpManager().isSyncUpComplete(localReplica));
    // make peer1 catch up with end offset
    replicationManager.updateTotalBytesReadByRemoteReplica(existingPartition,
        peerReplica1.getDataNodeId().getHostname(), peerReplica1.getReplicaPath(), sizeOfWhole);
    // Now, sync-up should complete and transition should be able to proceed.
    assertTrue("Inactive-To-Offline transition didn't complete within 1 sec",
        participantLatch.await(1, TimeUnit.SECONDS));
    assertTrue("Local store should be running since it would be stopped on offline to dropped transition",
        localStore.isStarted());
    storageManager.shutdown();
  }
Test INACTIVE -> OFFLINE transition on existing replica (both success and failure cases)
ambry-replication/src/test/java/com/github/ambry/replication/ReplicationTest.java