/**
* IMetadataToPM
*/
public void MetadataLocation(string metadataId, string location)
{
Console.WriteLine("METADATA LOCATION " + metadataId);
IMetadataToMetadata metadata = (IMetadataToMetadata)Activator.GetObject(
typeof(IMetadataToMetadata),
location);
metadatas[metadataId] = metadata;
}
// Tries to elect himself as the new master sending a vote to
// each alive metadata with its id:clock
// Other metadatas compare the votes, the one with the highest clock / lowest id
// wins, and returns that vote
public string Master()
{
if (fail)
{
throw new ProcessFailedException(id);
}
Console.WriteLine("MASTER ELECTION");
// if I'm the master
if (ImMaster)
{
return(id);
}
// checks if the master I know is down
try
{
return(metadatas[master].Master());
}
catch (ProcessFailedException) { }
// previous master is down, starting Uprising
MasterVote masterVote = new MasterVote(id, clock);
foreach (var entry in metadatas)
{
IMetadataToMetadata metadata = entry.Value;
try
{
// chooses better vote between previous master and the one from the metadata
masterVote = MasterVote.Choose(metadata.Uprising(masterVote), masterVote);
}
catch (ProcessFailedException) { }
}
// second round to confirm votes
foreach (var entry in metadatas)
{
IMetadataToMetadata metadata = entry.Value;
try
{
// chooses better vote between previous master and the one from the metadata
metadata.Uprising(masterVote, true);
}
catch (ProcessFailedException) { }
}
master = masterVote.Id;
return(master);
}
private void DataServerOnMetadatas(string dataServerId, string location, int sequence)
{
foreach (var entry in metadatas)
{
string metadataId = entry.Key;
IMetadataToMetadata metadata = entry.Value;
Thread request = new Thread(() =>
{
try
{
metadata.DataServerOnMetadata(dataServerId, location, sequence);
}
catch (ProcessFailedException) { }
});
request.Start();
}
}
private void DeleteOnMetadatas(string filename, int sequence)
{
foreach (var entry in metadatas)
{
string metadataId = entry.Key;
IMetadataToMetadata metadata = entry.Value;
Thread request = new Thread(() =>
{
try
{
metadata.DeleteOnMetadata(filename, sequence);
}
catch (ProcessFailedException) { }
});
request.Start();
}
}
private void CreateOnMetadatas(string clientId, string filename, int nbDataServers, int readQuorum, int writeQuorum, int sequence)
{
foreach (var entry in metadatas)
{
string metadataId = entry.Key;
IMetadataToMetadata metadata = entry.Value;
Thread request = new Thread(() =>
{
try
{
metadata.CreateOnMetadata(clientId, filename, nbDataServers, readQuorum, writeQuorum, sequence);
}
catch (ProcessFailedException) { }
});
request.Start();
}
}
private void MigrateFileOnMetadatas(string filename, string oldDataServerId, string newDataServerId, string oldLocalFilename, string newLocalFilename, int sequence)
{
foreach (var entry in metadatas)
{
string metadataId = entry.Key;
IMetadataToMetadata metadata = entry.Value;
Thread request = new Thread(() =>
{
try
{
metadata.MigrateFileOnMetadata(filename, oldDataServerId, newDataServerId, oldLocalFilename, newLocalFilename, sequence);
}
catch (ProcessFailedException) { }
});
request.Start();
}
}
public void Recover()
{
Console.WriteLine("RECOVER");
// metadata bootup
// since we force a metadata to start with recover
if (master == string.Empty)
{
MetadataBootup();
}
foreach (var entry in metadatas)
{
try
{
IMetadataToMetadata metadata = entry.Value;
// stops on the first not failed metadata
master = metadata.Master();
// sets fail to false so it starts receiving requests
int sequence = clock;
fail = false;
// updates its state with the master
if (!ImMaster)
{
MetadataDiff diff = metadatas[master].UpdateMetadata(id, sequence);
Console.WriteLine("--RECEIVING STATE UPDATE--");
log.MergeDiff(this, diff);
Console.WriteLine("--STATE UPDATE FINISHED--");
}
return;
}
catch (ProcessFailedException) { }
}
// sets fail to false so it starts receiving requests
master = id;
fail = false;
}
