public ViewChangeMessageProcessor(
MessageServiceClient messageServiceClient,
ReplicaState replicaState,
DoViewChangeXL doViewChange)
{
this.messageServiceClient = messageServiceClient;
this.replicaState = replicaState;
this.viewNumber = doViewChange.ViewNumber;
this.configuration = doViewChange.Configuration;
this.imTheManager = doViewChange.Configuration.Values.ToArray()[0].Equals(this.replicaState.MyUrl);
this.numberToWait = (doViewChange.Configuration.Count - 1) / 2;
this.messagesDoViewChange = 0;
this.bestDoViewChange = new DoViewChangeXL(
this.replicaState.ServerId,
this.viewNumber,
this.replicaState.ViewNumber,
this.configuration,
this.replicaState.TupleSpace,
this.replicaState.ClientTable,
this.replicaState.CommitNumber);
Log.Info("Changed to View Change State.");
// Stay in this state for a timeout
Task.Factory.StartNew(this.StartTimeout);
}
public ViewChangeMessageProcessor(
MessageServiceClient messageServiceClient,
ReplicaState replicaState,
int viewNumber,
SortedDictionary <string, Uri> configuration)
{
this.messageServiceClient = messageServiceClient;
this.replicaState = replicaState;
this.viewNumber = viewNumber;
this.configuration = configuration;
this.imTheManager = this.configuration.Values.ToArray()[0].Equals(this.replicaState.MyUrl);
this.numberToWait = this.replicaState.Configuration.Count / 2;
this.messagesDoViewChange = 0;
this.bestDoViewChange = new DoViewChangeXL(
this.replicaState.ServerId,
this.viewNumber,
this.replicaState.ViewNumber,
this.configuration,
this.replicaState.TupleSpace,
this.replicaState.ClientTable,
this.replicaState.CommitNumber);
Log.Info("Changed to View Change State.");
// Start the view change protocol
Task.Factory.StartNew(this.MulticastStartViewChange);
// Stay in this state for a timeout
Task.Factory.StartNew(this.StartTimeout);
}
public IResponse VisitDoViewChangeXL(DoViewChangeXL doViewChange)
{
if (doViewChange.ViewNumber <= this.replicaState.ViewNumber)
{
return(null);
}
if (this.imTheManager &&
doViewChange.ViewNumber == this.viewNumber &&
ConfigurationUtils.CompareConfigurations(doViewChange.Configuration, this.configuration))
{
Interlocked.Increment(ref this.messagesDoViewChange);
if (doViewChange.OldViewNumber == this.bestDoViewChange.OldViewNumber &&
doViewChange.CommitNumber > this.bestDoViewChange.CommitNumber)
{
this.bestDoViewChange = doViewChange;
}
if (doViewChange.OldViewNumber > this.bestDoViewChange.OldViewNumber)
{
this.bestDoViewChange = doViewChange;
}
this.CheckNumberAndSetNewConfiguration();
}
return(null);
}
public void ChangeToViewChange(DoViewChangeXL doViewChange)
{
lock (this.State) {
if (!(this.State is ViewChangeMessageProcessor))
{
this.State = new ViewChangeMessageProcessor(this.MessageServiceClient, this, doViewChange);
this.HandlerStateChanged.Set();
this.HandlerStateChanged.Reset();
}
}
}
public IResponse VisitDoViewChangeXL(DoViewChangeXL doViewChange)
{
if (doViewChange.ViewNumber <= this.replicaState.ViewNumber)
{
return(null);
}
lock (this) {
if (!(this.replicaState.State is ViewChangeMessageProcessor))
{
this.replicaState.ChangeToViewChange(doViewChange);
}
}
return(doViewChange.Accept(this.replicaState.State));
}
private void MulticastStartViewChange()
{
IMessage message = new StartViewChangeXL(this.replicaState.ServerId, this.viewNumber, this.configuration);
Uri[] currentConfiguration = this.replicaState.ReplicasUrl.ToArray();
IResponses responses = this.messageServiceClient.RequestMulticast(
message,
currentConfiguration,
this.replicaState.Configuration.Count / 2,
Timeout.TIMEOUT_VIEW_CHANGE,
true);
IResponse[] responsesVector = responses.ToArray();
// There was no quorum to accept the view change
if (responsesVector.Length < this.numberToWait)
{
Log.Debug($"There was no quorum for view change. " +
$"Just received {responsesVector.Length} from at least {this.numberToWait}");
this.replicaState.ChangeToNormalState();
return;
}
// In case I'm the manager, wait for f DoViewChange
if (this.imTheManager)
{
this.CheckNumberAndSetNewConfiguration();
}
else
{
// Else, send DoViewChange to leader
Uri leader = this.configuration.Values.ToArray()[0];
IMessage doViewMessage = new DoViewChangeXL(
this.replicaState.ServerId,
this.viewNumber,
this.replicaState.ViewNumber,
this.configuration,
this.replicaState.TupleSpace,
this.replicaState.ClientTable,
this.replicaState.CommitNumber);
this.messageServiceClient.Request(doViewMessage, leader, -1);
}
}
