//start receiving requests from the failed server
public void substituteFailedServer()
{
lock (Datastore.SERVEROBJECTS)
{
List <ServerObject> replaceList = Replica.WORKERSERVEROBJECTS;
//Send replaceList to sucessor, the data must always be in two place
// WARNING: Verificar se o sucessor é ele próprio
IWorkerReplica sucessor = (IWorkerReplica)Activator.GetObject(
typeof(IWorkerReplica), Replica.SUCESSOR + "WorkerReplica");
Datastore.SERVEROBJECTS.AddRange(replaceList);
//sucessor.update(replaceList);
// Instead of sending only the replace list, it is send all primary objects just to be sure
sucessor.update(Datastore.SERVEROBJECTS);
// debug info
Console.WriteLine("Printing worker main server objects:");
foreach (ServerObject o in Datastore.SERVEROBJECTS)
{
Console.WriteLine("\t UID= " + o.UID + " VALUE=" + o.VALUE);
}
}
}
internal static void notifyPredecessor(string predecessor, string myURL)
{
IWorkerReplica replica = (IWorkerReplica)Activator.GetObject(
typeof(IWorkerReplica), predecessor + "WorkerReplica");
worker_serverObjects = replica.setSucessor(myURL);
}
internal static void notifySucessor(string sucessor, string myURL)
{
IWorkerReplica replica = (IWorkerReplica)Activator.GetObject(
typeof(IWorkerReplica), sucessor + "WorkerReplica");
replica.setPredecessor(myURL);
}
// This server will fetch all primary data of sucessor and add it in his list of updates
public void fetch_data(string predecessor_url)
{
IWorkerReplica predecessor = (IWorkerReplica)Activator.GetObject(
typeof(IWorkerReplica), predecessor_url + "WorkerReplica");
List <ServerObject> fetched_data = predecessor.fetchData();
Replica.WORKERSERVEROBJECTS = fetched_data;
}
// WARNING: This function is obsolete
// The worker has a new predecessor (receives updates from a new one)
public void setPredecessor(string predecessorURL)
{
IWorkerReplica predecessor = (IWorkerReplica)Activator.GetObject(typeof(IWorkerReplica), predecessorURL + "WorkerReplica");
List <ServerObject> backupObjects = predecessor.fetchData();
Replica.update(backupObjects);
Console.WriteLine("AFTER SERVER FAILED MY PREDECESSOR IS = " + predecessor);
Replica.PREDECESSOR = predecessorURL;
}
// This server will fetch all primary data of sucessor and replace its own primary data
public void fetch_recover_data(string sucessor_url)
{
IWorkerReplica sucessor = (IWorkerReplica)Activator.GetObject(
typeof(IWorkerReplica), sucessor_url + "WorkerReplica");
List <ServerObject> recovered_data = sucessor.fetchRecoverData();
Replica.SUCESSOR = sucessor_url;
Datastore.SERVEROBJECTS = recovered_data;
Datastore.STATE = State.NORMAL;
Console.WriteLine("Datastore Recovered");
}
// Update function called by the workers, receives list of server objects
// from a given server. If worker_url does not exist in worker_serverObjects
// it means that it is a new server
//Send updated to sucessor, if sucessor died return false -> transaction abort
//call master to stabalize the system
internal static UpdateState updateSucessor(List <ServerObject> writtenObjects)
{
try
{
IWorkerReplica sucessor = (IWorkerReplica)Activator.GetObject(typeof(IWorkerReplica), Replica.SUCESSOR + "WorkerReplica");
sucessor.update(writtenObjects);
return(UpdateState.COMMIT);
}
catch (SocketException)
{
// manageFailedServer(Replica.SUCESSOR);
//updateSucessor(writtenObjects);
return(UpdateState.ABORT);
}
catch (System.IO.IOException)
{
//manageFailedServer(Replica.SUCESSOR);
//updateSucessor(writtenObjects);
return(UpdateState.ABORT);
}
}
