import akka.actor.ActorSelection;
import akka.actor.Cancellable;
import com.google.common.base.Preconditions;
-import java.util.ArrayList;
-import java.util.Collections;
import java.util.LinkedList;
-import java.util.List;
import java.util.Queue;
import java.util.UUID;
import java.util.concurrent.TimeUnit;
-import org.opendaylight.controller.cluster.raft.FollowerLogInformation.FollowerState;
+import javax.annotation.Nullable;
import org.opendaylight.controller.cluster.raft.base.messages.ApplyState;
+import org.opendaylight.controller.cluster.raft.base.messages.SnapshotComplete;
import org.opendaylight.controller.cluster.raft.behaviors.AbstractLeader;
import org.opendaylight.controller.cluster.raft.messages.AddServer;
import org.opendaylight.controller.cluster.raft.messages.AddServerReply;
import org.opendaylight.controller.cluster.raft.messages.FollowerCatchUpTimeout;
+import org.opendaylight.controller.cluster.raft.messages.RemoveServer;
+import org.opendaylight.controller.cluster.raft.messages.RemoveServerReply;
import org.opendaylight.controller.cluster.raft.messages.ServerChangeStatus;
+import org.opendaylight.controller.cluster.raft.messages.ServerRemoved;
import org.opendaylight.controller.cluster.raft.messages.UnInitializedFollowerSnapshotReply;
import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
import org.slf4j.Logger;
boolean handleMessage(Object message, RaftActor raftActor, ActorRef sender) {
if(message instanceof AddServer) {
- onAddServer((AddServer)message, raftActor, sender);
+ onAddServer((AddServer) message, raftActor, sender);
+ return true;
+ } else if(message instanceof RemoveServer) {
+ onRemoveServer((RemoveServer) message, raftActor, sender);
return true;
} else if (message instanceof FollowerCatchUpTimeout) {
- currentOperationState.onFollowerCatchupTimeout(raftActor, (FollowerCatchUpTimeout)message);
+ currentOperationState.onFollowerCatchupTimeout(raftActor, (FollowerCatchUpTimeout) message);
return true;
} else if (message instanceof UnInitializedFollowerSnapshotReply) {
currentOperationState.onUnInitializedFollowerSnapshotReply(raftActor,
- (UnInitializedFollowerSnapshotReply)message);
+ (UnInitializedFollowerSnapshotReply) message);
return true;
} else if(message instanceof ApplyState) {
return onApplyState((ApplyState) message, raftActor);
+ } else if(message instanceof SnapshotComplete) {
+ currentOperationState.onSnapshotComplete(raftActor);
+ return false;
} else {
return false;
}
}
+ private void onRemoveServer(RemoveServer removeServer, RaftActor raftActor, ActorRef sender) {
+ if(removeServer.getServerId().equals(raftActor.getLeaderId())){
+ // Removing current leader is not supported yet
+ // TODO: To properly support current leader removal we need to first implement transfer of leadership
+ LOG.debug("Cannot remove {} replica because it is the Leader", removeServer.getServerId());
+ sender.tell(new RemoveServerReply(ServerChangeStatus.NOT_SUPPORTED, raftActor.getLeaderId()), raftActor.getSelf());
+ } else if(!raftContext.getPeerIds().contains(removeServer.getServerId())) {
+ sender.tell(new RemoveServerReply(ServerChangeStatus.DOES_NOT_EXIST, raftActor.getLeaderId()), raftActor.getSelf());
+ } else {
+ onNewOperation(raftActor, new RemoveServerContext(removeServer, raftContext.getPeerAddress(removeServer.getServerId()), sender));
+ }
+ }
+
private boolean onApplyState(ApplyState applyState, RaftActor raftActor) {
Payload data = applyState.getReplicatedLogEntry().getData();
if(data instanceof ServerConfigurationPayload) {
void onUnInitializedFollowerSnapshotReply(RaftActor raftActor, UnInitializedFollowerSnapshotReply reply);
void onApplyState(RaftActor raftActor, ApplyState applyState);
+
+ void onSnapshotComplete(RaftActor raftActor);
}
/**
LOG.debug("onApplyState was called in state {}", this);
}
- protected void persistNewServerConfiguration(RaftActor raftActor, ServerOperationContext<?> operationContext){
- List <String> newConfig = new ArrayList<String>(raftContext.getPeerAddresses().keySet());
- newConfig.add(raftContext.getId());
-
- LOG.debug("{}: New server configuration : {}", raftContext.getId(), newConfig);
+ @Override
+ public void onSnapshotComplete(RaftActor raftActor) {
+ }
- ServerConfigurationPayload payload = new ServerConfigurationPayload(newConfig, Collections.<String>emptyList());
+ protected void persistNewServerConfiguration(RaftActor raftActor, ServerOperationContext<?> operationContext){
+ raftContext.setDynamicServerConfigurationInUse();
+ ServerConfigurationPayload payload = raftContext.getPeerServerInfo();
+ LOG.debug("{}: New server configuration : {}", raftContext.getId(), payload.getServerConfig());
raftActor.persistData(operationContext.getClientRequestor(), operationContext.getContextId(), payload);
currentOperationState = new Persisting(operationContext);
+
+ sendReply(raftActor, operationContext, ServerChangeStatus.OK);
}
protected void operationComplete(RaftActor raftActor, ServerOperationContext<?> operationContext,
- ServerChangeStatus status) {
-
- LOG.debug("{}: Returning {} for operation {}", raftContext.getId(), status, operationContext.getOperation());
+ @Nullable ServerChangeStatus replyStatus) {
+ if(replyStatus != null) {
+ sendReply(raftActor, operationContext, replyStatus);
+ }
- operationContext.getClientRequestor().tell(operationContext.newReply(status, raftActor.getLeaderId()),
- raftActor.self());
+ operationContext.operationComplete(raftActor, replyStatus);
currentOperationState = IDLE;
}
}
+ private void sendReply(RaftActor raftActor, ServerOperationContext<?> operationContext,
+ ServerChangeStatus status) {
+ LOG.debug("{}: Returning {} for operation {}", raftContext.getId(), status, operationContext.getOperation());
+
+ operationContext.getClientRequestor().tell(operationContext.newReply(status, raftActor.getLeaderId()),
+ raftActor.self());
+ }
+
@Override
public String toString() {
return getClass().getSimpleName();
// Sanity check - we could get an ApplyState from a previous operation that timed out so make
// sure it's meant for us.
if(operationContext.getContextId().equals(applyState.getIdentifier())) {
- LOG.info("{}: {} has been successfully replicated to a majority of followers",
+ LOG.info("{}: {} has been successfully replicated to a majority of followers", raftActor.getId(),
applyState.getReplicatedLogEntry().getData());
- operationComplete(raftActor, operationContext, ServerChangeStatus.OK);
+ operationComplete(raftActor, operationContext, null);
}
}
}
AddServerContext getAddServerContext() {
return addServerContext;
}
+
+ Cancellable newInstallSnapshotTimer(RaftActor raftActor) {
+ return raftContext.getActorSystem().scheduler().scheduleOnce(
+ new FiniteDuration(((raftContext.getConfigParams().getElectionTimeOutInterval().toMillis()) * 2),
+ TimeUnit.MILLISECONDS), raftContext.getActor(),
+ new FollowerCatchUpTimeout(addServerContext.getOperation().getNewServerId()),
+ raftContext.getActorSystem().dispatcher(), raftContext.getActor());
+ }
+
+ void handleOnFollowerCatchupTimeout(RaftActor raftActor, FollowerCatchUpTimeout followerTimeout) {
+ String serverId = followerTimeout.getNewServerId();
+
+ LOG.debug("{}: onFollowerCatchupTimeout for new server {}", raftContext.getId(), serverId);
+
+ // cleanup
+ raftContext.removePeer(serverId);
+
+ boolean isLeader = raftActor.isLeader();
+ if(isLeader) {
+ AbstractLeader leader = (AbstractLeader) raftActor.getCurrentBehavior();
+ leader.removeFollower(serverId);
+ }
+
+ operationComplete(raftActor, getAddServerContext(),
+ isLeader ? ServerChangeStatus.TIMEOUT : ServerChangeStatus.NO_LEADER);
+ }
+
}
/**
@Override
public void initiate(RaftActor raftActor) {
AbstractLeader leader = (AbstractLeader) raftActor.getCurrentBehavior();
-
AddServer addServer = getAddServerContext().getOperation();
LOG.debug("{}: Initiating {}", raftContext.getId(), addServer);
- raftContext.addToPeers(addServer.getNewServerId(), addServer.getNewServerAddress());
-
- // if voting member - initialize to VOTING_NOT_INITIALIZED
- FollowerState initialState = addServer.isVotingMember() ? FollowerState.VOTING_NOT_INITIALIZED :
- FollowerState.NON_VOTING;
- leader.addFollower(addServer.getNewServerId(), initialState);
+ if(raftContext.getPeerInfo(addServer.getNewServerId()) != null) {
+ operationComplete(raftActor, getAddServerContext(), ServerChangeStatus.ALREADY_EXISTS);
+ return;
+ }
- if(initialState == FollowerState.VOTING_NOT_INITIALIZED){
- LOG.debug("{}: Leader sending initiate capture snapshot to new follower {}", raftContext.getId(),
- addServer.getNewServerId());
+ VotingState votingState = addServer.isVotingMember() ? VotingState.VOTING_NOT_INITIALIZED :
+ VotingState.NON_VOTING;
+ raftContext.addToPeers(addServer.getNewServerId(), addServer.getNewServerAddress(), votingState);
- leader.initiateCaptureSnapshot(addServer.getNewServerId());
+ leader.addFollower(addServer.getNewServerId());
+ if(votingState == VotingState.VOTING_NOT_INITIALIZED){
// schedule the install snapshot timeout timer
- Cancellable installSnapshotTimer = raftContext.getActorSystem().scheduler().scheduleOnce(
- new FiniteDuration(((raftContext.getConfigParams().getElectionTimeOutInterval().toMillis()) * 2),
- TimeUnit.MILLISECONDS), raftContext.getActor(),
- new FollowerCatchUpTimeout(addServer.getNewServerId()),
- raftContext.getActorSystem().dispatcher(), raftContext.getActor());
-
- currentOperationState = new InstallingSnapshot(getAddServerContext(), installSnapshotTimer);
+ Cancellable installSnapshotTimer = newInstallSnapshotTimer(raftActor);
+ if(leader.initiateCaptureSnapshot(addServer.getNewServerId())) {
+ LOG.debug("{}: Initiating capture snapshot for new server {}", raftContext.getId(),
+ addServer.getNewServerId());
+
+ currentOperationState = new InstallingSnapshot(getAddServerContext(), installSnapshotTimer);
+ } else {
+ LOG.debug("{}: Snapshot already in progress - waiting for completion", raftContext.getId());
+
+ currentOperationState = new WaitingForPriorSnapshotComplete(getAddServerContext(),
+ installSnapshotTimer);
+ }
} else {
LOG.debug("{}: New follower is non-voting - directly persisting new server configuration",
raftContext.getId());
@Override
public void onFollowerCatchupTimeout(RaftActor raftActor, FollowerCatchUpTimeout followerTimeout) {
- String serverId = followerTimeout.getNewServerId();
-
- LOG.debug("{}: onFollowerCatchupTimeout: {}", raftContext.getId(), serverId);
-
- AbstractLeader leader = (AbstractLeader) raftActor.getCurrentBehavior();
-
- // cleanup
- raftContext.removePeer(serverId);
- leader.removeFollower(serverId);
+ handleOnFollowerCatchupTimeout(raftActor, followerTimeout);
- LOG.warn("{}: Timeout occured for new server {} while installing snapshot", raftContext.getId(), serverId);
-
- operationComplete(raftActor, getAddServerContext(), ServerChangeStatus.TIMEOUT);
+ LOG.warn("{}: Timeout occured for new server {} while installing snapshot", raftContext.getId(),
+ followerTimeout.getNewServerId());
}
@Override
// Sanity check to guard against receiving an UnInitializedFollowerSnapshotReply from a prior
// add server operation that timed out.
- if(getAddServerContext().getOperation().getNewServerId().equals(followerId)) {
+ if(getAddServerContext().getOperation().getNewServerId().equals(followerId) && raftActor.isLeader()) {
AbstractLeader leader = (AbstractLeader) raftActor.getCurrentBehavior();
- FollowerLogInformation followerLogInformation = leader.getFollower(followerId);
+ raftContext.getPeerInfo(followerId).setVotingState(VotingState.VOTING);
+ leader.updateMinReplicaCount();
+
+ persistNewServerConfiguration(raftActor, getAddServerContext());
installSnapshotTimer.cancel();
+ } else {
+ LOG.debug("{}: Dropping UnInitializedFollowerSnapshotReply for server {}: {}",
+ raftContext.getId(), followerId,
+ !raftActor.isLeader() ? "not leader" : "server Id doesn't match");
+ }
+ }
+ }
- followerLogInformation.setFollowerState(FollowerState.VOTING);
- leader.updateMinReplicaCountAndMinIsolatedLeaderPeerCount();
+ /**
+ * The AddServer operation state for when there is a snapshot already in progress. When the current
+ * snapshot completes, it initiates an install snapshot.
+ */
+ private class WaitingForPriorSnapshotComplete extends AddServerState {
+ private final Cancellable snapshotTimer;
- persistNewServerConfiguration(raftActor, getAddServerContext());
+ WaitingForPriorSnapshotComplete(AddServerContext addServerContext, Cancellable snapshotTimer) {
+ super(addServerContext);
+ this.snapshotTimer = Preconditions.checkNotNull(snapshotTimer);
+ }
+
+ @Override
+ public void onSnapshotComplete(RaftActor raftActor) {
+ LOG.debug("{}: onSnapshotComplete", raftContext.getId());
+
+ if(!raftActor.isLeader()) {
+ LOG.debug("{}: No longer the leader", raftContext.getId());
+ return;
+ }
+
+ AbstractLeader leader = (AbstractLeader) raftActor.getCurrentBehavior();
+ if(leader.initiateCaptureSnapshot(getAddServerContext().getOperation().getNewServerId())) {
+ LOG.debug("{}: Initiating capture snapshot for new server {}", raftContext.getId(),
+ getAddServerContext().getOperation().getNewServerId());
+
+ currentOperationState = new InstallingSnapshot(getAddServerContext(),
+ newInstallSnapshotTimer(raftActor));
+
+ snapshotTimer.cancel();
}
}
+
+ @Override
+ public void onFollowerCatchupTimeout(RaftActor raftActor, FollowerCatchUpTimeout followerTimeout) {
+ handleOnFollowerCatchupTimeout(raftActor, followerTimeout);
+
+ LOG.warn("{}: Timeout occured for new server {} while waiting for prior snapshot to complete",
+ raftContext.getId(), followerTimeout.getNewServerId());
+ }
}
/**
abstract Object newReply(ServerChangeStatus status, String leaderId);
abstract InitialOperationState newInitialOperationState(RaftActorServerConfigurationSupport support);
+
+ abstract void operationComplete(RaftActor raftActor, ServerChangeStatus serverChangeStatus);
}
/**
InitialOperationState newInitialOperationState(RaftActorServerConfigurationSupport support) {
return support.new InitialAddServerState(this);
}
+
+ @Override
+ void operationComplete(RaftActor raftActor, ServerChangeStatus serverChangeStatus) {
+
+ }
+ }
+
+ private abstract class RemoveServerState extends AbstractOperationState {
+ private final RemoveServerContext removeServerContext;
+
+
+ protected RemoveServerState(RemoveServerContext removeServerContext) {
+ this.removeServerContext = Preconditions.checkNotNull(removeServerContext);
+
+ }
+
+ public RemoveServerContext getRemoveServerContext() {
+ return removeServerContext;
+ }
+
+ }
+
+ private class InitialRemoveServerState extends RemoveServerState implements InitialOperationState{
+
+ protected InitialRemoveServerState(RemoveServerContext removeServerContext) {
+ super(removeServerContext);
+ }
+
+ @Override
+ public void initiate(RaftActor raftActor) {
+ raftContext.removePeer(getRemoveServerContext().getOperation().getServerId());
+ persistNewServerConfiguration(raftActor, getRemoveServerContext());
+ }
+ }
+
+ private static class RemoveServerContext extends ServerOperationContext<RemoveServer> {
+ private final String peerAddress;
+
+ RemoveServerContext(RemoveServer operation, String peerAddress, ActorRef clientRequestor) {
+ super(operation, clientRequestor);
+ this.peerAddress = peerAddress;
+ }
+
+ @Override
+ Object newReply(ServerChangeStatus status, String leaderId) {
+ return new RemoveServerReply(status, leaderId);
+ }
+
+ @Override
+ InitialOperationState newInitialOperationState(RaftActorServerConfigurationSupport support) {
+ return support.new InitialRemoveServerState(this);
+ }
+
+ @Override
+ void operationComplete(RaftActor raftActor, ServerChangeStatus serverChangeStatus) {
+ if(peerAddress != null) {
+ raftActor.context().actorSelection(peerAddress).tell(new ServerRemoved(getOperation().getServerId()), raftActor.getSelf());
+ }
+ }
+
}
}
Code Review / controller.git / blobdiff