private Tuple <KadContactNode, KadValue> LookupValue(KadId valueId, out SortedSet <KadContactNode> retSortList)
{
var closestNodes = Owner.BucketList.GetClosestNodes(valueId, MaxConcurrentThreads);
SortedSet <KadContactNode> shortList = new SortedSet <KadContactNode>(closestNodes, new KadId.KadIdToBaseComparator(valueId));
retSortList = shortList;
if (shortList.Count == 0)
{
return(null);
}
SortedSet <KadId> queriedNodes = new SortedSet <KadId>(new KadId.KadIdToIdComparator());
KadId closestId = shortList.Min.Id;
SemaphoreSlim tasksSemaphore = new SemaphoreSlim(MaxConcurrentThreads);
KadContactNode returnedNode = null;
KadValue value = null;
//Should do fine for small alpha
List <Task> tasks = new List <Task>();
while (queriedNodes.Count < ReplicationCount)
{
var shortListSnapshot = shortList.Where((n) => !queriedNodes.Contains(n.Id)).ToList();
foreach (var node in shortListSnapshot)
{
tasks.Add(Task.Run(() => {
var response = Owner.FindValue(node, valueId);
if (response != null)
{
if (response.Type == MessageType.FindNode)
{
foreach (var contact in response.Contacts)
{
shortList.Add(contact);
}
}
else if (response.Type == MessageType.FindValue)
{
value = new KadValue(valueId, DateTime.Now, response.Payload);
returnedNode = node;
}
}
tasksSemaphore.Release();
}));
queriedNodes.Add(node.Id);
tasksSemaphore.Wait();
}
Task.WaitAll(tasks.ToArray());
tasks.Clear();
if ((shortList.Min.Id ^ closestId) >= closestId)
{
break;
}
closestId = shortList.Min.Id;
}
return(value != null ? new Tuple <KadContactNode, KadValue>(returnedNode, value) : null);
}
public void StoreValue()
{
KadNode ownerNode = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555));
KadNode node1 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55556));
KadNode node2 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55557));
KadNode node3 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55558));
KadNode node4 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55559));
node1.BucketList.Put(new KadContactNode(node2.Id, node2.EndPoint));
node1.BucketList.Put(new KadContactNode(node3.Id, node3.EndPoint));
node1.BucketList.Put(new KadContactNode(node4.Id, node4.EndPoint));
KadValue value = new KadValue(KadId.GenerateRandom(), DateTime.UtcNow, new byte[20]);
KadHashTable hashTable = new KadHashTable(ownerNode, new KadContactNode(node1.Id, node1.EndPoint));
hashTable.StoreValue(value);
Assert.IsTrue(ownerNode.Storage.OwnerValues.Count() == 1);
Assert.IsTrue(ownerNode.Storage.OwnerValues.First().Id.GetNumericValue() == value.Id.GetNumericValue());
Assert.IsTrue(node1.Storage.Values.Count() == 1);
Assert.IsTrue(node1.Storage.Values.First().Id.GetNumericValue() == value.Id.GetNumericValue());
Assert.IsTrue(node2.Storage.Values.Count() == 1);
Assert.IsTrue(node2.Storage.Values.First().Id.GetNumericValue() == value.Id.GetNumericValue());
Assert.IsTrue(node3.Storage.Values.Count() == 1);
Assert.IsTrue(node3.Storage.Values.First().Id.GetNumericValue() == value.Id.GetNumericValue());
Assert.IsTrue(node4.Storage.Values.Count() == 1);
Assert.IsTrue(node4.Storage.Values.First().Id.GetNumericValue() == value.Id.GetNumericValue());
}
private void ReplicateValue(KadValue value)
{
var closestNodes = Owner.BucketList.GetClosestNodes(value.Id, ReplicationCount);
foreach (var node in closestNodes)
{
Owner.StoreValue(node, value);
}
}
public void StoreValue(KadValue value)
{
if (!Owner.Storage.Contains(value.Id))
{
Owner.Storage.PutOwnerVal(value);
}
ReplicateValue(value);
}
/// <summary>
/// Store value in contact
/// </summary>
/// <param name="node">Contact node</param>
/// <param name="value">Value to store</param>
/// <returns>true, if node stored value</returns>
public bool StoreValue(KadContactNode node, KadValue value) //TODO: support chunking
{
NodeMessage storeValueMsg = new NodeMessage.Builder()
.SetType(MessageType.StoreValue)
.SetOriginator(Id)
.SetIsRequest(true)
.SetKadValueAsPayload(value)
.Build();
storeValueMsg.AddCallback(UpdateLastSeen);
var response = _server.SendMessageSync(node.EndPoint, storeValueMsg, TimeoutInMSec).Response;
return(response != null && response.Type == MessageType.CanStoreValue && response.Payload[0] > 0);
}
public void StoreValue()
{
KadNode node1 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555));
KadNode node2 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55556));
KadValue val = new KadValue(KadId.GenerateRandom(), DateTime.Now, new byte[20]);
node1.BucketList.Put(new KadContactNode(node2.Id, node2.EndPoint));
Assert.IsTrue(node1.StoreValue(node2.Id, val));
KadValue node2Val = node2.Storage.Get(val.Id);
Assert.IsTrue(val.Id.GetNumericValue() == node2Val.Id.GetNumericValue());
node1.Shutdown();
node2.Shutdown();
}
public void StoreValue_CantStore()
{
KadNode node1 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555));
KadNode node2 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55556));
for (int i = 0; i < 20; i++)
{
var value = new KadValue(kademlia_dht.Base.KadId.GenerateRandom(), DateTime.UtcNow, new byte[20]);
node2.Storage.Put(value);
Thread.Sleep(500);
}
KadValue val = new KadValue(KadId.GenerateRandom(), DateTime.UtcNow, new byte[20]);
node1.BucketList.Put(new KadContactNode(node2.Id, node2.EndPoint));
Assert.IsFalse(node1.StoreValue(node2.Id, val));
node1.Shutdown();
node2.Shutdown();
}
/// <summary>
/// Checks whether value is expired
/// Algorithm described in http://xlattice.sourceforge.net/components/protocol/kademlia/specs.html#expiration
/// </summary>
/// <param name="kadVal">Value to be checked</param>
/// <returns>True if value expired</returns>
public bool IsValueExpired(KadValue kadVal)
{
var valBucket = BucketList.GetBucket(kadVal.Id);
int cA = 0, cB = 0;
foreach (var bucket in BucketList.Buckets.Where((b) => b.Id < valBucket.Id))
{
cA += bucket.NodesCount;
}
foreach (var contact in valBucket.GetNodes())
{
if (contact.Id < kadVal.Id)
{
cB++;
}
}
int c = cA + cB;
if (c == 0)
{
return(true);
}
int secondsBtw = (int)(DateTime.UtcNow - kadVal.Timestamp).TotalSeconds;
if (c > Storage.Size())
{
if (secondsBtw >= ValueExpirationInSec)
{
return(true);
}
}
else if (secondsBtw >= ValueExpirationInSec * Math.Exp(Storage.Size() / c))
{
return(true);
}
return(false);
}
public void IsValueExpired_Exp()
{
KadId ownerNodeId = KadId.GenerateRandom();
for (int i = 2; i < ownerNodeId.Value.Length; i++)
{
ownerNodeId.Value[i] = 255;
}
ownerNodeId.Value[0] = 0;
ownerNodeId.Value[1] = 0;
KadNode node1 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555), ownerNodeId);
byte[] baseId = new byte[20];
for (int i = 1; i < 21; i++) //fill up random bucket
{
baseId[19] = (byte)i;
KadContactNode contact = new KadContactNode(new KadId(baseId), new IPEndPoint(IPAddress.Loopback, 20000));
node1.BucketList.Put(contact);
}
//baseId[0] = 255;
//baseId[1] = 255;
//baseId[19] = 0;
//for(int i = 1; i < 20; i++) {
// baseId[3] = (byte)i;
// ContactNode contact = new ContactNode(new KadId(baseId), new IPEndPoint(IPAddress.Loopback, 20000));
// node1.BucketList.Put(contact);
//}
KadValue nonExpiredVal = new KadValue(node1.BucketList.Buckets.Aggregate((o, n) => o.Id < n.Id ? n : o).GetNodes()
.Aggregate((o, n) => o.Id > n.Id ? n : o).Id, DateTime.UtcNow.AddSeconds(-(node1.ValueExpirationInSec + 1)), new byte[20]);
Assert.IsFalse(node1.IsValueExpired(nonExpiredVal));
KadValue expiredVal = new KadValue(nonExpiredVal.Id, DateTime.UtcNow.AddSeconds(-(((node1.ValueExpirationInSec + 1) * Math.Exp(20 / 19)))), new byte[20]);
Assert.IsTrue(node1.IsValueExpired(expiredVal));
node1.Shutdown();
}
public void IsValueExpired_GoodAmountOfCloseContacts()
{
KadId ownerNodeId = KadId.GenerateRandom();
for (int i = 2; i < ownerNodeId.Value.Length; i++)
{
ownerNodeId.Value[i] = 255;
}
ownerNodeId.Value[0] = 0;
ownerNodeId.Value[1] = 0;
KadNode node1 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555), ownerNodeId);
byte[] baseId = new byte[20];
baseId[0] = 255;
for (int i = 0; i < 20; i++) //fill up random bucket
{
baseId[19] = (byte)i;
KadContactNode contact = new KadContactNode(new KadId(baseId), new IPEndPoint(IPAddress.Loopback, 20000));
node1.BucketList.Put(contact);
}
baseId[1] = 255;
for (int i = 0; i < 20; i++)
{
baseId[19] = (byte)i;
KadContactNode contact = new KadContactNode(new KadId(baseId), new IPEndPoint(IPAddress.Loopback, 20000));
node1.BucketList.Put(contact);
}
KadValue value = new KadValue(node1.BucketList.Buckets.Aggregate((o, n) => o.Id < n.Id ? n : o).GetNodes().Aggregate((o, n) => o.Id > n.Id ? n : o).Id, DateTime.UtcNow, new byte[20]);
Assert.IsFalse(node1.IsValueExpired(value));
KadValue expiredVal = new KadValue(value.Id, value.Timestamp.AddSeconds(-(node1.ValueExpirationInSec + 1)), new byte[20]);
Assert.IsTrue(node1.IsValueExpired(expiredVal));
node1.Shutdown();
}
public void RetrieveValues()
{
KadNode node1 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555));
KadNode node2 = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55556));
List <KadValue> values = new List <KadValue>(20);
for (int i = 0; i < 20; i++)
{
var value = new KadValue(kademlia_dht.Base.KadId.GenerateRandom(), DateTime.UtcNow, new byte[20]);
values.Add(value);
node2.Storage.Put(value);
Thread.Sleep(500);
}
values = values.OrderBy((v) => v.Id.GetNumericValue()).ToList();
node1.BucketList.Put(new KadContactNode(node2.Id, node2.EndPoint));
var foundVal = node1.FindValue(node2.Id, values.First().Id);
Assert.AreEqual(values.First().Id.GetNumericValue(), foundVal.Value.Id.GetNumericValue());
node1.Shutdown();
node2.Shutdown();
}
public void KadNodeUnit_SaveLoadBucketsAndValues()
{
KadNode kadNode = new KadNode(new System.Net.IPEndPoint(IPAddress.Loopback, 55555));
KadNodeUnit unit = new KadNodeUnit(kadNode);
for (int i = 0; i < 20; i++)
{
var contact = new kademlia_dht.Base.KadContactNode(kademlia_dht.Base.KadId.GenerateRandom(), new System.Net.IPEndPoint(IPAddress.Loopback, 20000));
unit.Node.BucketList.Put(contact);
Thread.Sleep(1000);
}
byte[] value = new byte[20];
for (int i = 0; i < 20; i++)
{
value[0] = (byte)(i + 1);
var valId = new KadId(value);
value[19] = (byte)i;
var kadValue = new KadValue(valId, DateTime.UtcNow, value);
if (i % 3 == 0)
{
byte[] ownId = new byte[20];
ownId[3] = (byte)i;
unit.Node.Storage.PutOwnerVal(new KadValue(new KadId(ownId), DateTime.UtcNow, value));
}
else
{
unit.Node.Storage.Put(kadValue);
}
Thread.Sleep(1000);
}
string savePath = "nodewithbuckets.xml";
unit.SaveToFile(savePath);
unit.Stop();
KadNodeUnit unit2 = new KadNodeUnit(savePath);
Assert.IsTrue(unit2.Node.Id.GetNumericValue() == unit.Node.Id.GetNumericValue());
Assert.IsTrue(unit2.Node.EndPoint.Address.ToString() == unit.Node.EndPoint.Address.ToString());
Assert.IsTrue(unit2.Node.EndPoint.Port == unit.Node.EndPoint.Port);
CollectionAssert.AreEqual(unit2.Node.BucketList
.Buckets.Select((b) => b.Id).ToList(), unit.Node.BucketList.Buckets.Select((b) => b.Id).ToList());
CollectionAssert.AreEqual(unit2.Node.BucketList
.Buckets
.SelectMany((b) => b.GetNodes())
.Select((n) => n.Id.GetNumericValue())
.OrderBy((id) => id)
.ToList(),
unit.Node.BucketList
.Buckets
.SelectMany((b) => b.GetNodes())
.Select((n) => n.Id.GetNumericValue())
.OrderBy((id) => id)
.ToList());
CollectionAssert.AreEqual(unit2.Node.Storage.Values
.Select((v) => v.Id.GetNumericValue())
.OrderBy((id) => id)
.ToList(),
unit.Node.Storage.Values
.Select((v) => v.Id.GetNumericValue())
.OrderBy((id) => id)
.ToList());
CollectionAssert.AreEqual(unit2.Node.Storage.OwnerValues
.Select((v) => v.Id.GetNumericValue())
.OrderBy((id) => id)
.ToList(),
unit.Node.Storage.OwnerValues
.Select((v) => v.Id.GetNumericValue())
.OrderBy((id) => id)
.ToList());
CollectionAssert.AreEqual(unit2.Node.Storage.OwnerValues
.Select((v) => v.Timestamp)
.OrderBy((t) => t)
.ToList(),
unit.Node.Storage.OwnerValues
.Select((v) => v.Timestamp)
.OrderBy((t) => t)
.ToList());
}
/// <summary>
/// Store value in contact
/// </summary>
/// <param name="node">Contact node</param>
/// <param name="value">Value to store</param>
/// <returns>true, if node stored value</returns>
public bool StoreValue(KadId id, KadValue value)
{
var bucket = BucketList.GetBucket(id);
return(StoreValue(bucket.GetNode(id), value));
}
