Java Code Examples for org.apache.ratis.client.RaftClient#getClientRpc()

void runTestBasicRetry(CLUSTER cluster) throws Exception {
  RaftTestUtil.waitForLeader(cluster);
  final RaftPeerId leaderId = cluster.getLeaderAndSendFirstMessage(false).getId();
  long oldLastApplied = cluster.getLeader().getState().getLastAppliedIndex();

  final RaftClient client = cluster.createClient(leaderId);
  final RaftClientRpc rpc = client.getClientRpc();
  final long callId = 999;
  final long seqNum = 111;
  RaftClientRequest r = cluster.newRaftClientRequest(client.getId(), leaderId,
      callId, seqNum, new SimpleMessage("message"));
  assertReply(rpc.sendRequest(r), client, callId);

  // retry with the same callId
  for (int i = 0; i < 5; i++) {
    assertReply(rpc.sendRequest(r), client, callId);
  }

  assertServer(cluster, client.getId(), callId, oldLastApplied);
  client.close();
}
 

@Test
public void testRetryOnStateMachineException() throws Exception {
  final RaftProperties prop = getProperties();
  prop.setClass(MiniRaftCluster.STATEMACHINE_CLASS_KEY,
      StateMachineWithException.class, StateMachine.class);
  final MiniRaftCluster cluster = newCluster(3);
  cluster.start();

  RaftPeerId leaderId = RaftTestUtil.waitForLeader(cluster).getId();

  cluster.getLeaderAndSendFirstMessage(true);
  long oldLastApplied = cluster.getLeader().getState().getLastAppliedIndex();

  final RaftClient client = cluster.createClient(leaderId);
  final RaftClientRpc rpc = client.getClientRpc();
  final long callId = 999;
  final long seqNum = 111;
  final SimpleMessage message = new SimpleMessage("message");
  final RaftClientRequest r = cluster.newRaftClientRequest(client.getId(), leaderId, callId, seqNum, message);
  RaftClientReply reply = rpc.sendRequest(r);
  Assert.assertFalse(reply.isSuccess());
  Assert.assertNotNull(reply.getStateMachineException());

  // retry with the same callId
  for (int i = 0; i < 5; i++) {
    reply = rpc.sendRequest(r);
    Assert.assertEquals(client.getId(), reply.getClientId());
    Assert.assertEquals(callId, reply.getCallId());
    Assert.assertFalse(reply.isSuccess());
    Assert.assertNotNull(reply.getStateMachineException());
  }

  long leaderApplied = cluster.getLeader().getState().getLastAppliedIndex();
  // make sure retry cache has the entry
  for (RaftServerImpl server : cluster.iterateServerImpls()) {
    LOG.info("check server " + server.getId());
    if (server.getState().getLastAppliedIndex() < leaderApplied) {
      Thread.sleep(1000);
    }
    Assert.assertNotNull(
        RaftServerTestUtil.getRetryEntry(server, client.getId(), callId));
    final RaftLog log = server.getState().getLog();
    RaftTestUtil.logEntriesContains(log, oldLastApplied + 1, log.getNextIndex(), message);
  }

  client.close();
  cluster.shutdown();
}
 

@Test
public void testRetryOnExceptionDuringReplication() throws Exception {
  final RaftProperties prop = getProperties();
  prop.setClass(MiniRaftCluster.STATEMACHINE_CLASS_KEY,
      StateMachineWithException.class, StateMachine.class);
  final MiniRaftCluster cluster = newCluster(3);
  cluster.start();
  RaftTestUtil.waitForLeader(cluster);
  RaftServerImpl leader = cluster.getLeader();
  RaftPeerId leaderId = leader.getId();
  cluster.getLeaderAndSendFirstMessage(true);
  // turn on the preAppend failure switch
  failPreAppend = true;
  final RaftClient client = cluster.createClient(leaderId);
  final RaftClientRpc rpc = client.getClientRpc();
  final long callId = 999;
  final long seqNum = 111;
  RaftClientRequest r = cluster.newRaftClientRequest(client.getId(), leaderId,
      callId, seqNum, new RaftTestUtil.SimpleMessage("message"));
  RaftClientReply reply = rpc.sendRequest(r);
  Objects.requireNonNull(reply.getStateMachineException());

  RetryCache.CacheEntry oldEntry = RaftServerTestUtil.getRetryEntry(
      leader, client.getId(), callId);
  Assert.assertNotNull(oldEntry);
  Assert.assertTrue(RaftServerTestUtil.isRetryCacheEntryFailed(oldEntry));

  // At this point of time the old leader would have stepped down. wait for
  // leader election to complete
  RaftTestUtil.waitForLeader(cluster);
  leader = cluster.getLeader();
  leaderId = leader.getId();
  // retry
  r = cluster.newRaftClientRequest(client.getId(), leaderId,
      callId, seqNum, new RaftTestUtil.SimpleMessage("message"));
  reply = rpc.sendRequest(r);
  Objects.requireNonNull(reply.getStateMachineException());

  RetryCache.CacheEntry currentEntry = RaftServerTestUtil.getRetryEntry(
      leader, client.getId(), callId);
  Assert.assertNotNull(currentEntry);
  Assert.assertTrue(RaftServerTestUtil.isRetryCacheEntryFailed(currentEntry));
  Assert.assertNotEquals(oldEntry, currentEntry);
  failPreAppend = false;
  client.close();
}
 

void runTestRetryOnNewLeader(CLUSTER cluster) throws Exception {
  RaftTestUtil.waitForLeader(cluster);
  final RaftPeerId leaderId = cluster.getLeaderAndSendFirstMessage(false).getId();

  final RaftClient client = cluster.createClient(leaderId);
  RaftClientRpc rpc = client.getClientRpc();
  final long callId = 999;
  final long seqNum = 111;
  RaftClientRequest r = cluster.newRaftClientRequest(client.getId(), leaderId,
      callId, seqNum, new SimpleMessage("message"));
  assertReply(rpc.sendRequest(r), client, callId);
  long oldLastApplied = cluster.getLeader().getState().getLastAppliedIndex();

  // trigger the reconfiguration, make sure the original leader is kicked out
  PeerChanges change = cluster.addNewPeers(2, true);
  RaftPeer[] allPeers = cluster.removePeers(2, true,
      asList(change.newPeers)).allPeersInNewConf;
  // trigger setConfiguration
  cluster.setConfiguration(allPeers);

  final RaftPeerId newLeaderId = JavaUtils.attempt(() -> {
    final RaftPeerId id = RaftTestUtil.waitForLeader(cluster).getId();
    Assert.assertNotEquals(leaderId, id);
    return id;
  }, 10, TimeDuration.valueOf(100, TimeUnit.MILLISECONDS), "wait for a leader different than " + leaderId, LOG);
  Assert.assertNotEquals(leaderId, newLeaderId);
  // same clientId and callId in the request
  r = cluster.newRaftClientRequest(client.getId(), newLeaderId,
      callId, seqNum, new SimpleMessage("message"));
  rpc.addServers(Arrays.asList(change.newPeers));
  for (int i = 0; i < 10; i++) {
    try {
      assertReply(rpc.sendRequest(r), client, callId);
      LOG.info("successfully sent out the retry request_" + i);
    } catch (Exception e) {
      LOG.info("hit exception while retrying the same request: " + r, e);
    }
    Thread.sleep(100);
  }

  // check the new leader and make sure the retry did not get committed
  Assert.assertEquals(0, count(cluster.getLeader().getState().getLog(), oldLastApplied + 1));
  client.close();
}