// Get the Physical server where a key is mapped to
public Server GetServerForKey(String key)
{
Server serverHoldingKey;
if (this.hashRing.Count == 0)
{
return(null);
}
// Get the hash for the key
uint hashKey = MyHasher.To32BitHash(key);
if (this.hashRing.ContainsKey(hashKey))
{
serverHoldingKey = this.hashRing[hashKey];
}
else
{
uint[] sortedKeys = this.hashRing.Keys.ToArray();
//Find the first server key greater than the hashkey
uint firstServerKey = sortedKeys.FirstOrDefault(x => x >= hashKey);
// Get the Server at that Hashkey
serverHoldingKey = this.hashRing[firstServerKey];
}
return(serverHoldingKey);
}
public void removeServerFromHashRing(Server server)
{
for (int i = 0; i < numberOfReplicas; i++)
{
//Fuse the server ip with the replica number
string serverIdentity = String.Concat(server.ipAddress, ":", i);
//Get the hash key of the server
uint hashKey = MyHasher.To32BitHash(serverIdentity);
//Insert the server at the hashkey in the Sorted Dictionary
this.hashRing.Remove(hashKey);
}
}