*/
package org.opendaylight.controller.cluster.raft;
+import static java.util.Objects.requireNonNull;
+
import akka.actor.ActorRef;
import akka.actor.ActorSelection;
import akka.actor.Cancellable;
-import com.google.common.base.Preconditions;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Map;
import java.util.Queue;
import java.util.UUID;
-import javax.annotation.Nullable;
+import org.eclipse.jdt.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.base.messages.TimeoutNow;
private OperationState currentOperationState = IDLE;
- RaftActorServerConfigurationSupport(RaftActor raftActor) {
+ RaftActorServerConfigurationSupport(final RaftActor raftActor) {
this.raftActor = raftActor;
this.raftContext = raftActor.getRaftActorContext();
}
- boolean handleMessage(Object message, ActorRef sender) {
+ boolean handleMessage(final Object message, final ActorRef sender) {
if (message instanceof AddServer) {
onAddServer((AddServer) message, sender);
return true;
}
}
- void onNewLeader(String leaderId) {
+ void onNewLeader(final String leaderId) {
currentOperationState.onNewLeader(leaderId);
}
- private void onChangeServersVotingStatus(ChangeServersVotingStatus message, ActorRef sender) {
+ private void onChangeServersVotingStatus(final ChangeServersVotingStatus message, final ActorRef sender) {
LOG.debug("{}: onChangeServersVotingStatus: {}, state: {}", raftContext.getId(), message,
currentOperationState);
}
}
- private void onRemoveServer(RemoveServer removeServer, ActorRef sender) {
+ private void onRemoveServer(final RemoveServer removeServer, final ActorRef sender) {
LOG.debug("{}: onRemoveServer: {}, state: {}", raftContext.getId(), removeServer, currentOperationState);
boolean isSelf = removeServer.getServerId().equals(raftContext.getId());
if (isSelf && !raftContext.hasFollowers()) {
}
}
- private boolean onApplyState(ApplyState applyState) {
+ private boolean onApplyState(final ApplyState applyState) {
Payload data = applyState.getReplicatedLogEntry().getData();
if (data instanceof ServerConfigurationPayload) {
currentOperationState.onApplyState(applyState);
}
/**
- * The algorithm for AddServer is as follows:
+ * Add a server. The algorithm for AddServer is as follows:
* <ul>
* <li>Add the new server as a peer.</li>
* <li>Add the new follower to the leader.</li>
* <li>Respond to caller with TIMEOUT.</li>
* </ul>
*/
- private void onAddServer(AddServer addServer, ActorRef sender) {
+ private void onAddServer(final AddServer addServer, final ActorRef sender) {
LOG.debug("{}: onAddServer: {}, state: {}", raftContext.getId(), addServer, currentOperationState);
onNewOperation(new AddServerContext(addServer, sender));
}
- private void onNewOperation(ServerOperationContext<?> operationContext) {
+ private void onNewOperation(final ServerOperationContext<?> operationContext) {
if (raftActor.isLeader()) {
currentOperationState.onNewOperation(operationContext);
} else {
* Abstract base class for a server operation FSM state. Handles common behavior for all states.
*/
private abstract class OperationState {
- void onNewOperation(ServerOperationContext<?> operationContext) {
+ void onNewOperation(final ServerOperationContext<?> operationContext) {
// We're currently processing another operation so queue it to be processed later.
LOG.debug("{}: Server operation already in progress - queueing {}", raftContext.getId(),
pendingOperationsQueue.add(operationContext);
}
- void onServerOperationTimeout(ServerOperationTimeout timeout) {
+ void onServerOperationTimeout(final ServerOperationTimeout timeout) {
LOG.debug("onServerOperationTimeout should not be called in state {}", this);
}
- void onUnInitializedFollowerSnapshotReply(UnInitializedFollowerSnapshotReply reply) {
+ void onUnInitializedFollowerSnapshotReply(final UnInitializedFollowerSnapshotReply reply) {
LOG.debug("onUnInitializedFollowerSnapshotReply was called in state {}", this);
}
- void onApplyState(ApplyState applyState) {
+ void onApplyState(final ApplyState applyState) {
LOG.debug("onApplyState was called in state {}", this);
}
}
- void onNewLeader(String newLeader) {
+ void onNewLeader(final String newLeader) {
}
- protected void persistNewServerConfiguration(ServerOperationContext<?> operationContext) {
+ protected void persistNewServerConfiguration(final ServerOperationContext<?> operationContext) {
raftContext.setDynamicServerConfigurationInUse();
ServerConfigurationPayload payload = raftContext.getPeerServerInfo(
sendReply(operationContext, ServerChangeStatus.OK);
}
- protected void operationComplete(ServerOperationContext<?> operationContext,
- @Nullable ServerChangeStatus replyStatus) {
+ protected void operationComplete(final ServerOperationContext<?> operationContext,
+ final @Nullable ServerChangeStatus replyStatus) {
if (replyStatus != null) {
sendReply(operationContext, replyStatus);
}
}
}
- protected void sendReply(ServerOperationContext<?> operationContext, ServerChangeStatus status) {
+ protected void sendReply(final ServerOperationContext<?> operationContext, final ServerChangeStatus status) {
LOG.debug("{}: Returning {} for operation {}", raftContext.getId(), status,
operationContext.getOperation());
raftActor.self());
}
- Cancellable newTimer(Object message) {
+ Cancellable newTimer(final Object message) {
return newTimer(raftContext.getConfigParams().getElectionTimeOutInterval().$times(2), message);
}
- Cancellable newTimer(FiniteDuration timeout, Object message) {
+ Cancellable newTimer(final FiniteDuration timeout, final Object message) {
return raftContext.getActorSystem().scheduler().scheduleOnce(
timeout, raftContext.getActor(), message,
raftContext.getActorSystem().dispatcher(), raftContext.getActor());
*/
private final class Idle extends OperationState {
@Override
- public void onNewOperation(ServerOperationContext<?> operationContext) {
+ public void onNewOperation(final ServerOperationContext<?> operationContext) {
operationContext.newInitialOperationState(RaftActorServerConfigurationSupport.this).initiate();
}
@Override
- public void onApplyState(ApplyState applyState) {
+ public void onApplyState(final ApplyState applyState) {
// Noop - we override b/c ApplyState is called normally for followers in the idle state.
}
}
private final Cancellable timer;
private boolean timedOut = false;
- Persisting(ServerOperationContext<?> operationContext, Cancellable timer) {
+ Persisting(final ServerOperationContext<?> operationContext, final Cancellable timer) {
this.operationContext = operationContext;
this.timer = timer;
}
@Override
- public void onApplyState(ApplyState applyState) {
+ public void onApplyState(final ApplyState applyState) {
// 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())) {
}
@Override
- public void onServerOperationTimeout(ServerOperationTimeout timeout) {
+ public void onServerOperationTimeout(final ServerOperationTimeout timeout) {
LOG.warn("{}: Timeout occured while replicating the new server configuration for {}", raftContext.getId(),
timeout.getLoggingContext());
}
@Override
- public void onNewOperation(ServerOperationContext<?> newOperationContext) {
+ public void onNewOperation(final ServerOperationContext<?> newOperationContext) {
if (timedOut) {
sendReply(newOperationContext, ServerChangeStatus.PRIOR_REQUEST_CONSENSUS_TIMEOUT);
} else {
private abstract class AddServerState extends OperationState {
private final AddServerContext addServerContext;
- AddServerState(AddServerContext addServerContext) {
+ AddServerState(final AddServerContext addServerContext) {
this.addServerContext = addServerContext;
}
return newTimer(new ServerOperationTimeout(addServerContext.getOperation().getNewServerId()));
}
- void handleInstallSnapshotTimeout(ServerOperationTimeout timeout) {
+ void handleInstallSnapshotTimeout(final ServerOperationTimeout timeout) {
String serverId = timeout.getLoggingContext();
LOG.debug("{}: handleInstallSnapshotTimeout for new server {}", raftContext.getId(), serverId);
* snapshot capture, if necessary.
*/
private final class InitialAddServerState extends AddServerState implements InitialOperationState {
- InitialAddServerState(AddServerContext addServerContext) {
+ InitialAddServerState(final AddServerContext addServerContext) {
super(addServerContext);
}
private final class InstallingSnapshot extends AddServerState {
private final Cancellable installSnapshotTimer;
- InstallingSnapshot(AddServerContext addServerContext, Cancellable installSnapshotTimer) {
+ InstallingSnapshot(final AddServerContext addServerContext, final Cancellable installSnapshotTimer) {
super(addServerContext);
- this.installSnapshotTimer = Preconditions.checkNotNull(installSnapshotTimer);
+ this.installSnapshotTimer = requireNonNull(installSnapshotTimer);
}
@Override
- public void onServerOperationTimeout(ServerOperationTimeout timeout) {
+ public void onServerOperationTimeout(final ServerOperationTimeout timeout) {
handleInstallSnapshotTimeout(timeout);
LOG.warn("{}: Timeout occured for new server {} while installing snapshot", raftContext.getId(),
}
@Override
- public void onUnInitializedFollowerSnapshotReply(UnInitializedFollowerSnapshotReply reply) {
+ public void onUnInitializedFollowerSnapshotReply(final UnInitializedFollowerSnapshotReply reply) {
LOG.debug("{}: onUnInitializedFollowerSnapshotReply: {}", raftContext.getId(), reply);
String followerId = reply.getFollowerId();
private final class WaitingForPriorSnapshotComplete extends AddServerState {
private final Cancellable snapshotTimer;
- WaitingForPriorSnapshotComplete(AddServerContext addServerContext, Cancellable snapshotTimer) {
+ WaitingForPriorSnapshotComplete(final AddServerContext addServerContext, final Cancellable snapshotTimer) {
super(addServerContext);
- this.snapshotTimer = Preconditions.checkNotNull(snapshotTimer);
+ this.snapshotTimer = requireNonNull(snapshotTimer);
}
@Override
}
@Override
- public void onServerOperationTimeout(ServerOperationTimeout timeout) {
+ public void onServerOperationTimeout(final ServerOperationTimeout timeout) {
handleInstallSnapshotTimeout(timeout);
LOG.warn("{}: Timeout occured for new server {} while waiting for prior snapshot to complete",
private final ActorRef clientRequestor;
private final Identifier contextId;
- ServerOperationContext(T operation, ActorRef clientRequestor) {
+ ServerOperationContext(final T operation, final ActorRef clientRequestor) {
this.operation = operation;
this.clientRequestor = clientRequestor;
contextId = new ServerOperationContextIdentifier();
return clientRequestor;
}
- void operationComplete(RaftActor raftActor, boolean succeeded) {
+ void operationComplete(final RaftActor raftActor, final boolean succeeded) {
}
- boolean includeSelfInNewConfiguration(RaftActor raftActor) {
+ boolean includeSelfInNewConfiguration(final RaftActor raftActor) {
return true;
}
* Stores context information for an AddServer operation.
*/
private static class AddServerContext extends ServerOperationContext<AddServer> {
- AddServerContext(AddServer addServer, ActorRef clientRequestor) {
+ AddServerContext(final AddServer addServer, final ActorRef clientRequestor) {
super(addServer, clientRequestor);
}
@Override
- Object newReply(ServerChangeStatus status, String leaderId) {
+ Object newReply(final ServerChangeStatus status, final String leaderId) {
return new AddServerReply(status, leaderId);
}
@Override
- InitialOperationState newInitialOperationState(RaftActorServerConfigurationSupport support) {
+ InitialOperationState newInitialOperationState(final RaftActorServerConfigurationSupport support) {
return support.new InitialAddServerState(this);
}
private abstract class RemoveServerState extends OperationState {
private final RemoveServerContext removeServerContext;
- protected RemoveServerState(RemoveServerContext removeServerContext) {
- this.removeServerContext = Preconditions.checkNotNull(removeServerContext);
+ protected RemoveServerState(final RemoveServerContext removeServerContext) {
+ this.removeServerContext = requireNonNull(removeServerContext);
}
private final class InitialRemoveServerState extends RemoveServerState implements InitialOperationState {
- protected InitialRemoveServerState(RemoveServerContext removeServerContext) {
+ protected InitialRemoveServerState(final RemoveServerContext removeServerContext) {
super(removeServerContext);
}
public void initiate() {
String serverId = getRemoveServerContext().getOperation().getServerId();
raftContext.removePeer(serverId);
- ((AbstractLeader)raftActor.getCurrentBehavior()).removeFollower(serverId);
+ AbstractLeader leader = (AbstractLeader)raftActor.getCurrentBehavior();
+ leader.removeFollower(serverId);
+ leader.updateMinReplicaCount();
persistNewServerConfiguration(getRemoveServerContext());
}
private static class RemoveServerContext extends ServerOperationContext<RemoveServer> {
private final String peerAddress;
- RemoveServerContext(RemoveServer operation, String peerAddress, ActorRef clientRequestor) {
+ RemoveServerContext(final RemoveServer operation, final String peerAddress, final ActorRef clientRequestor) {
super(operation, clientRequestor);
this.peerAddress = peerAddress;
}
@Override
- Object newReply(ServerChangeStatus status, String leaderId) {
+ Object newReply(final ServerChangeStatus status, final String leaderId) {
return new RemoveServerReply(status, leaderId);
}
@Override
- InitialOperationState newInitialOperationState(RaftActorServerConfigurationSupport support) {
+ InitialOperationState newInitialOperationState(final RaftActorServerConfigurationSupport support) {
return support.new InitialRemoveServerState(this);
}
@Override
- void operationComplete(RaftActor raftActor, boolean succeeded) {
+ void operationComplete(final RaftActor raftActor, final boolean succeeded) {
if (peerAddress != null) {
raftActor.context().actorSelection(peerAddress).tell(
new ServerRemoved(getOperation().getServerId()), raftActor.getSelf());
}
@Override
- boolean includeSelfInNewConfiguration(RaftActor raftActor) {
+ boolean includeSelfInNewConfiguration(final RaftActor raftActor) {
return !getOperation().getServerId().equals(raftActor.getId());
}
private static class ChangeServersVotingStatusContext extends ServerOperationContext<ChangeServersVotingStatus> {
private final boolean tryToElectLeader;
- ChangeServersVotingStatusContext(ChangeServersVotingStatus convertMessage, ActorRef clientRequestor,
- boolean tryToElectLeader) {
+ ChangeServersVotingStatusContext(final ChangeServersVotingStatus convertMessage, final ActorRef clientRequestor,
+ final boolean tryToElectLeader) {
super(convertMessage, clientRequestor);
this.tryToElectLeader = tryToElectLeader;
}
@Override
- InitialOperationState newInitialOperationState(RaftActorServerConfigurationSupport support) {
+ InitialOperationState newInitialOperationState(final RaftActorServerConfigurationSupport support) {
return support.new ChangeServersVotingStatusState(this, tryToElectLeader);
}
@Override
- Object newReply(ServerChangeStatus status, String leaderId) {
+ Object newReply(final ServerChangeStatus status, final String leaderId) {
return new ServerChangeReply(status, leaderId);
}
@Override
- void operationComplete(final RaftActor raftActor, boolean succeeded) {
+ void operationComplete(final RaftActor raftActor, final boolean succeeded) {
// If this leader changed to non-voting we need to step down as leader so we'll try to transfer
// leadership.
boolean localServerChangedToNonVoting = Boolean.FALSE.equals(getOperation()
if (succeeded && localServerChangedToNonVoting) {
LOG.debug("Leader changed to non-voting - trying leadership transfer");
raftActor.becomeNonVoting();
+ } else if (raftActor.isLeader()) {
+ raftActor.onVotingStateChangeComplete();
}
}
private final ChangeServersVotingStatusContext changeVotingStatusContext;
private final boolean tryToElectLeader;
- ChangeServersVotingStatusState(ChangeServersVotingStatusContext changeVotingStatusContext,
- boolean tryToElectLeader) {
+ ChangeServersVotingStatusState(final ChangeServersVotingStatusContext changeVotingStatusContext,
+ final boolean tryToElectLeader) {
this.changeVotingStatusContext = changeVotingStatusContext;
this.tryToElectLeader = tryToElectLeader;
}
private final ChangeServersVotingStatusContext operationContext;
private final Cancellable timer;
- WaitingForLeaderElected(ChangeServersVotingStatusContext operationContext,
- ServerConfigurationPayload previousServerConfig) {
+ WaitingForLeaderElected(final ChangeServersVotingStatusContext operationContext,
+ final ServerConfigurationPayload previousServerConfig) {
this.operationContext = operationContext;
this.previousServerConfig = previousServerConfig;
}
@Override
- void onNewLeader(String newLeader) {
+ void onNewLeader(final String newLeader) {
if (newLeader == null) {
return;
}
}
@Override
- void onServerOperationTimeout(ServerOperationTimeout timeout) {
+ void onServerOperationTimeout(final ServerOperationTimeout timeout) {
LOG.warn("{}: Leader election timed out - cannot apply operation {}",
raftContext.getId(), timeout.getLoggingContext());
static class ServerOperationTimeout {
private final String loggingContext;
- ServerOperationTimeout(String loggingContext) {
- this.loggingContext = Preconditions.checkNotNull(loggingContext, "loggingContext should not be null");
+ ServerOperationTimeout(final String loggingContext) {
+ this.loggingContext = requireNonNull(loggingContext, "loggingContext should not be null");
}
String getLoggingContext() {