// ======= ======= ======= ======= =======
/// <summary>
/// Someone is pinging us. Register the contact and respond.
/// </summary>
public Contact Ping(Contact sender)
{
Validate.IsFalse <SendingQueryToSelfException>(sender.ID == ourContact.ID, "Sender should not be ourself!");
SendKeyValuesIfNewContact(sender);
bucketList.AddContact(sender);
return(ourContact);
}
protected IBucketList SetupSplitFailure(IBucketList bucketList = null)
{
// force host node ID to < 2^159 so the node ID is not in the 2^159 ... 2^160 range
byte[] bhostID = new byte[20];
bhostID[19] = 0x7F;
ID hostID = new ID(bhostID);
Contact dummyContact = new Contact(new VirtualProtocol(), hostID);
((VirtualProtocol)dummyContact.Protocol).Node = new Node(dummyContact, new VirtualStorage());
bucketList = bucketList ?? new BucketList(hostID, dummyContact);
// Also add a contact in this 0 - 2^159 range, arbitrarily something not our host ID.
// This ensures that only one bucket split will occur after 20 nodes with ID >= 2^159 are added,
// otherwise, buckets will in the 2^159 ... 2^160 space.
dummyContact = new Contact(new VirtualProtocol(), ID.One);
((VirtualProtocol)dummyContact.Protocol).Node = new Node(dummyContact, new VirtualStorage());
bucketList.AddContact(new Contact(dummyContact.Protocol, ID.One));
Assert.IsTrue(bucketList.Buckets.Count == 1, "Bucket split should not have occurred.");
Assert.IsTrue(bucketList.Buckets[0].Contacts.Count == 1, "Expected 1 contact in bucket 0.");
// make sure contact ID's all have the same 5 bit prefix and are in the 2^159 ... 2^160 - 1 space
byte[] bcontactID = new byte[20];
bcontactID[19] = 0x80;
// 1000 xxxx prefix, xxxx starts at 1000 (8)
// this ensures that all the contacts in a bucket match only the prefix as only the first 5 bits are shared.
// |----| shared range
// 1000 1000 ...
// 1000 1100 ...
// 1000 1110 ...
byte shifter = 0x08;
int pos = 19;
Constants.K.ForEach(() =>
{
bcontactID[pos] |= shifter;
ID contactID = new ID(bcontactID);
dummyContact = new Contact(new VirtualProtocol(), ID.One);
((VirtualProtocol)dummyContact.Protocol).Node = new Node(dummyContact, new VirtualStorage());
bucketList.AddContact(new Contact(dummyContact.Protocol, contactID));
shifter >>= 1;
if (shifter == 0)
{
shifter = 0x80;
--pos;
}
});
return(bucketList);
}
// ======= ======= ======= ======= =======
/// <summary>
/// Someone is pinging us. Register the contact and respond.
/// </summary>
public Contact Ping(Contact sender)
{
Validate.IsFalse <SendingQueryToSelfException>(sender.ID == ourContact.ID, "Sender should not be ourself!");
// Not in spec...ping the sender to verify sender.
RpcError err = sender.Protocol.PingBack(ourContact);
if (!err.HasError)
{
SendKeyValuesIfNewContact(sender);
bucketList.AddContact(sender);
}
return(ourContact);
}
public void ForceFailedAddTest()
{
Contact dummyContact = new Contact(new VirtualProtocol(), ID.Zero);
((VirtualProtocol)dummyContact.Protocol).Node = new Node(dummyContact, new VirtualStorage());
IBucketList bucketList = SetupSplitFailure();
Assert.IsTrue(bucketList.Buckets.Count == 2, "Bucket split should have occurred.");
Assert.IsTrue(bucketList.Buckets[0].Contacts.Count == 1, "Expected 1 contact in bucket 0.");
Assert.IsTrue(bucketList.Buckets[1].Contacts.Count == 20, "Expected 20 contacts in bucket 1.");
// This next contact should not split the bucket as depth == 5 and therefore adding the contact will fail.
// Any unique ID >= 2^159 will do.
byte[] id = new byte[20];
id[19] = 0x80;
Contact newContact = new Contact(dummyContact.Protocol, new ID(id));
bucketList.AddContact(newContact);
Assert.IsTrue(bucketList.Buckets.Count == 2, "Bucket split should not have occurred.");
Assert.IsTrue(bucketList.Buckets[0].Contacts.Count == 1, "Expected 1 contact in bucket 0.");
Assert.IsTrue(bucketList.Buckets[1].Contacts.Count == 20, "Expected 20 contacts in bucket 1.");
// Verify CanSplit -> Evict did not happen.
Assert.IsFalse(bucketList.Buckets[1].Contacts.Contains(newContact), "Expected new contact NOT to replace an older contact.");
}
public void NonRespondingContactDelayedEvictionTest()
{
// Create a DHT so we have an eviction handler.
Dht dht = new Dht(ID.Zero, new VirtualProtocol(), () => null, new Router());
//Contact dummyContact = new Contact(new VirtualProtocol(), ID.Zero);
//((VirtualProtocol)dummyContact.Protocol).Node = new Node(dummyContact, new VirtualStorage());
IBucketList bucketList = SetupSplitFailure(dht.Node.BucketList);
Assert.IsTrue(bucketList.Buckets.Count == 2, "Bucket split should have occurred.");
Assert.IsTrue(bucketList.Buckets[0].Contacts.Count == 1, "Expected 1 contact in bucket 0.");
Assert.IsTrue(bucketList.Buckets[1].Contacts.Count == 20, "Expected 20 contacts in bucket 1.");
// The bucket is now full. Pick the first contact, as it is last seen (they are added in chronological order.)
Contact nonRespondingContact = bucketList.Buckets[1].Contacts[0];
// Since the protocols are shared, we need to assign a unique protocol for this node for testing.
VirtualProtocol vpUnresponding = new VirtualProtocol(((VirtualProtocol)nonRespondingContact.Protocol).Node, false);
nonRespondingContact.Protocol = vpUnresponding;
// Setup the next new contact (it can respond.)
Contact nextNewContact = new Contact(dht.Contact.Protocol, ID.Zero.SetBit(159));
bucketList.AddContact(nextNewContact);
Assert.IsTrue(bucketList.Buckets[1].Contacts.Count == 20, "Expected 20 contacts in bucket 1.");
// Verify CanSplit -> Evict happened.
Assert.IsTrue(dht.PendingContacts.Count == 1, "Expected one pending contact.");
Assert.IsTrue(dht.PendingContacts.Contains(nextNewContact), "Expected pending contact to be the 21st contact.");
Assert.IsTrue(dht.EvictionCount.Count == 1, "Expected one contact to be pending eviction.");
}
public void NonRespondingContactEvictedTest()
{
// Create a DHT so we have an eviction handler.
Dht dht = new Dht(ID.Zero, new VirtualProtocol(), () => null, new Router());
//Contact dummyContact = new Contact(new VirtualProtocol(), ID.Zero);
//((VirtualProtocol)dummyContact.Protocol).Node = new Node(dummyContact, new VirtualStorage());
IBucketList bucketList = SetupSplitFailure(dht.Node.BucketList);
Assert.IsTrue(bucketList.Buckets.Count == 2, "Bucket split should have occurred.");
Assert.IsTrue(bucketList.Buckets[0].Contacts.Count == 1, "Expected 1 contact in bucket 0.");
Assert.IsTrue(bucketList.Buckets[1].Contacts.Count == 20, "Expected 20 contacts in bucket 1.");
// The bucket is now full. Pick the first contact, as it is last seen (they are added in chronological order.)
Contact nonRespondingContact = bucketList.Buckets[1].Contacts[0];
// Since the protocols are shared, we need to assign a unique protocol for this node for testing.
VirtualProtocol vpUnresponding = new VirtualProtocol(((VirtualProtocol)nonRespondingContact.Protocol).Node, false);
nonRespondingContact.Protocol = vpUnresponding;
// Setup the next new contact (it can respond.)
Contact nextNewContact = new Contact(dht.Contact.Protocol, ID.Zero.SetBit(159));
// Hit the non-responding contact EVICTION_LIMIT times, which will trigger the eviction algorithm.
Constants.EVICTION_LIMIT.ForEach(() => bucketList.AddContact(nextNewContact));
Assert.IsTrue(bucketList.Buckets[1].Contacts.Count == 20, "Expected 20 contacts in bucket 1.");
// Verify CanSplit -> Pending eviction happened.
Assert.IsTrue(dht.PendingContacts.Count == 0, "Pending contact list should now be empty.");
Assert.IsFalse(bucketList.Buckets.SelectMany(b => b.Contacts).Contains(nonRespondingContact), "Expected bucket to NOT contain non-responding contact.");
Assert.IsTrue(bucketList.Buckets.SelectMany(b => b.Contacts).Contains(nextNewContact), "Expected bucket to contain new contact.");
Assert.IsTrue(dht.EvictionCount.Count == 0, "Expected no contacts to be pending eviction.");
}