// Get the Physical server where a key is mapped to
public Server GetServerForKey(String key)
{
Server serverHoldingKey;
if (_hashRing.Count == 0)
{
return(null);
}
// Get the hash for the key
uint hashKey = FNVHash.To32BitFnv1aHash(key);
if (_hashRing.ContainsKey(hashKey))
{
serverHoldingKey = this._hashRing[hashKey];
}
else
{
uint[] sortedKeys = _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 = _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 = FNVHash.To32BitFnv1aHash(serverIdentity);
//Insert the server at the hashkey in the Sorted Dictionary
_hashRing.Remove(hashKey);
}
}