private void handleForwardedReadyTransaction(ForwardedReadyTransaction forwardedReady) {
LOG.debug(
"{}: handleForwardedReadyTransaction for {}",
persistenceId(),
forwardedReady.getTransactionID());
boolean isLeaderActive = isLeaderActive();
if (isLeader() && isLeaderActive) {
commitCoordinator.handleForwardedReadyTransaction(forwardedReady, getSender(), this);
} else {
ActorSelection leader = getLeader();
if (!isLeaderActive || leader == null) {
messageRetrySupport.addMessageToRetry(
forwardedReady,
getSender(),
"Could not commit transaction " + forwardedReady.getTransactionID());
} else {
LOG.debug("{}: Forwarding ForwardedReadyTransaction to leader {}", persistenceId(), leader);
ReadyLocalTransaction readyLocal =
new ReadyLocalTransaction(
forwardedReady.getTransactionID(),
forwardedReady.getTransaction().getSnapshot(),
forwardedReady.isDoImmediateCommit());
readyLocal.setRemoteVersion(getCurrentBehavior().getLeaderPayloadVersion());
leader.forward(readyLocal, getContext());
}
}
}
private void handleReadyLocalTransaction(final ReadyLocalTransaction message) {
LOG.debug(
"{}: handleReadyLocalTransaction for {}", persistenceId(), message.getTransactionID());
boolean isLeaderActive = isLeaderActive();
if (isLeader() && isLeaderActive) {
try {
commitCoordinator.handleReadyLocalTransaction(message, getSender(), this);
} catch (Exception e) {
LOG.error(
"{}: Error handling ReadyLocalTransaction for Tx {}",
persistenceId(),
message.getTransactionID(),
e);
getSender().tell(new akka.actor.Status.Failure(e), getSelf());
}
} else {
ActorSelection leader = getLeader();
if (!isLeaderActive || leader == null) {
messageRetrySupport.addMessageToRetry(
message, getSender(), "Could not commit transaction " + message.getTransactionID());
} else {
LOG.debug("{}: Forwarding ReadyLocalTransaction to leader {}", persistenceId(), leader);
message.setRemoteVersion(getCurrentBehavior().getLeaderPayloadVersion());
leader.forward(message, getContext());
}
}
}
private void handleBatchedModifications(BatchedModifications batched) {
// This message is sent to prepare the modifications transaction directly on the Shard as an
// optimization to avoid the extra overhead of a separate ShardTransaction actor. On the last
// BatchedModifications message, the caller sets the ready flag in the message indicating
// modifications are complete. The reply contains the cohort actor path (this actor) for the
// caller
// to initiate the 3-phase commit. This also avoids the overhead of sending an additional
// ReadyTransaction message.
// If we're not the leader then forward to the leader. This is a safety measure - we shouldn't
// normally get here if we're not the leader as the front-end (TransactionProxy) should
// determine
// the primary/leader shard. However with timing and caching on the front-end, there's a small
// window where it could have a stale leader during leadership transitions.
//
boolean isLeaderActive = isLeaderActive();
if (isLeader() && isLeaderActive) {
handleBatchedModificationsLocal(batched, getSender());
} else {
ActorSelection leader = getLeader();
if (!isLeaderActive || leader == null) {
messageRetrySupport.addMessageToRetry(
batched, getSender(), "Could not commit transaction " + batched.getTransactionID());
} else {
// TODO: what if this is not the first batch and leadership changed in between batched
// messages?
// We could check if the commitCoordinator already has a cached entry and forward all the
// previous
// batched modifications.
LOG.debug("{}: Forwarding BatchedModifications to leader {}", persistenceId(), leader);
leader.forward(batched, getContext());
}
}
}
@Override
protected synchronized void removeRegistration() {
if (listenerRegistrationActor != null) {
listenerRegistrationActor.tell(
CloseDataTreeChangeListenerRegistration.getInstance(), ActorRef.noSender());
listenerRegistrationActor = null;
}
dataChangeListenerActor.tell(PoisonPill.getInstance(), ActorRef.noSender());
}
/**
* Sends a snapshot chunk to a given follower InstallSnapshot should qualify as a heartbeat too.
*/
private void sendSnapshotChunk(ActorSelection followerActor, String followerId) {
try {
if (snapshot.isPresent()) {
ByteString nextSnapshotChunk =
getNextSnapshotChunk(followerId, snapshot.get().getSnapshotBytes());
// Note: the previous call to getNextSnapshotChunk has the side-effect of adding
// followerId to the followerToSnapshot map.
FollowerToSnapshot followerToSnapshot = mapFollowerToSnapshot.get(followerId);
followerActor.tell(
new InstallSnapshot(
currentTerm(),
context.getId(),
snapshot.get().getLastIncludedIndex(),
snapshot.get().getLastIncludedTerm(),
nextSnapshotChunk,
followerToSnapshot.incrementChunkIndex(),
followerToSnapshot.getTotalChunks(),
Optional.of(followerToSnapshot.getLastChunkHashCode()))
.toSerializable(),
actor());
if (LOG.isDebugEnabled()) {
LOG.debug(
"{}: InstallSnapshot sent to follower {}, Chunk: {}/{}",
logName(),
followerActor.path(),
followerToSnapshot.getChunkIndex(),
followerToSnapshot.getTotalChunks());
}
}
} catch (IOException e) {
LOG.error("{}: InstallSnapshot failed for Leader.", logName(), e);
}
}
private void setListenerRegistrationActor(final ActorSelection actor) {
if (actor == null) {
LOG.debug("Ignoring null actor on {}", this);
return;
}
synchronized (this) {
if (!isClosed()) {
this.listenerRegistrationActor = actor;
return;
}
}
// This registration has already been closed, notify the actor
actor.tell(CloseDataTreeChangeListenerRegistration.getInstance(), null);
}
private void sendAppendEntriesToFollower(
ActorSelection followerActor,
long followerNextIndex,
List<ReplicatedLogEntry> entries,
String followerId) {
AppendEntries appendEntries =
new AppendEntries(
currentTerm(),
context.getId(),
prevLogIndex(followerNextIndex),
prevLogTerm(followerNextIndex),
entries,
context.getCommitIndex(),
super.getReplicatedToAllIndex(),
context.getPayloadVersion());
if (!entries.isEmpty() || LOG.isTraceEnabled()) {
LOG.debug(
"{}: Sending AppendEntries to follower {}: {}", logName(), followerId, appendEntries);
}
followerActor.tell(appendEntries.toSerializable(), actor());
}
{
ActorSelection selection = getContext().actorSelection("/user/another");
selection.tell(new Identify(identifyId), getSelf());
}