private async Task DiscoverNodes()
{
IsRunning = false;
var callback = new Action(() =>
{
if (ConnectEvent != null)
{
IsRunning = true;
ConnectEvent(this, EventArgs.Empty);
}
});
try
{
var peers = _peersRepository.GetAll();
if (peers.Any()) // DISCOVER THE PEERS FROM THE REPOSITORY.
{
await DiscoverNodesViaStore(peers);
callback();
return;
}
if (!_isSeedNode) // DISCOVER THE PEERS FROM THE SEEDS.
{
await DiscoverNodesViaSeeds();
}
}
catch (Exception) { if (_isSeedNode)
{
callback();
}
return; }
callback();
}
public Message Receive(Message message, PeerConnector peer, P2PNetworkConnector p2pNetworkConnector)
{
var blockChain = _blockChainStore.GetBlockChain();
var smartContract = _smartContractStore.GetSmartContracts();
if (message.GetCommandName() == Constants.MessageNames.Version) // RETURNS VERSION.
{
var msg = message as VersionMessage;
var instance = PeersStore.Instance();
var transmittingNode = instance.GetMyIpAddress();
var receivingNode = msg.TransmittingNode;
return(new VersionMessage(transmittingNode, receivingNode, msg.Nonce, msg.UserAgent, msg.StartHeight, msg.Relay, msg.MessageHeader.Network));
}
if (message.GetCommandName() == Constants.MessageNames.Ping) // RETURNS PONG.
{
var msg = message as PingMessage;
var pong = new PongMessage(msg.Nonce, msg.MessageHeader.Network);
return(pong);
}
if (message.GetCommandName() == Constants.MessageNames.Verack) // RETURNS VERACK MESSAGE.
{
var msg = message as VerackMessage;
return(new VerackMessage(msg.MessageHeader.Network));
}
if (message.GetCommandName() == Constants.MessageNames.Addr) // RETURNS THE ADDRS.
{
var msg = message as AddrMessage;
if (msg.IpAddresses != null)
{
foreach (var ipAddress in msg.IpAddresses)
{
PeerEventStore.Instance().NewPeer(ipAddress);
}
}
return(null);
}
if (message.GetCommandName() == Constants.MessageNames.GetAddr) // RETURNS THE ADDRS.
{
var msg = message as GetAddressMessage;
var ipAdrLst = _peersStorage.GetAll();
var response = new AddrMessage(new CompactSize {
Size = (ulong)ipAdrLst.Count()
}, msg.MessageHeader.Network);
foreach (var ipAdr in ipAdrLst)
{
response.IpAddresses.Add(ipAdr);
}
return(response);
}
if (message.GetCommandName() == Constants.MessageNames.MemPool) // RETURNS THE INVENTORY.
{
var msg = message as MemPoolMessage;
var memoryPool = MemoryPool.Instance();
var txIds = memoryPool.GetTransactions().Select(t => t.Transaction.GetTxId());
var inventories = new List <Inventory>();
foreach (var txId in txIds)
{
inventories.Add(new Inventory(InventoryTypes.MSG_TX, txId));
}
return(new InventoryMessage(inventories, msg.MessageHeader.Network));
}
if (message.GetCommandName() == Constants.MessageNames.GetData) // RETURNS ALL THE DATA TO THE PEER.
{
var msg = message as GetDataMessage;
var messages = Execute(msg);
if (messages != null)
{
foreach (var m in messages)
{
peer.Execute(m.Serialize());
}
}
return(null);
}
if (message.GetCommandName() == Constants.MessageNames.Transaction) // ADD TRANSACTION INTO MEMORY POOL & BROADCAST IT.
{
var msg = message as TransactionMessage;
AddTransaction(msg.Transaction);
MemoryPool.Instance().Remove(msg.Transaction);
p2pNetworkConnector.Broadcast(msg.Transaction, msg.MessageHeader.Ipv6);
return(null);
}
if (message.GetCommandName() == Constants.MessageNames.Block) // ADD THE BLOCK.
{
var msg = message as BlockMessage;
_blockValidator.Check(msg.Block);
if (msg.Block.Transactions != null)
{
MemoryPool.Instance().Remove(msg.Block.Transactions.Select(tx => tx.GetTxId()));
}
smartContract.AddBlock(msg.Block);
smartContract.Commit();
blockChain.AddBlock(msg.Block);
}
if (message.GetCommandName() == Constants.MessageNames.NotFound) // SOME INVENTORIES ARE NOT FOUND.
{
return(null);
}
if (message.GetCommandName() == Constants.MessageNames.GetBlocks) // RETURN THE BLOCKS : https://bitcoin.org/en/developer-reference#getblocks
{
var msg = message as GetBlocksMessage;
int lastBlockHeight = -1;
foreach (var blockHash in msg.BlockHashes)
{
lastBlockHeight = blockChain.GetBlockHeight(blockHash);
if (lastBlockHeight != -1)
{
goto Found;
}
}
Found:
var currentBlockHeight = blockChain.GetCurrentBlockHeight();
if (currentBlockHeight == lastBlockHeight)
{
return(new InventoryMessage(new List <Inventory>(), msg.MessageHeader.Network));
}
var nbBlocks = currentBlockHeight - lastBlockHeight;
if (lastBlockHeight == -1)
{
nbBlocks = currentBlockHeight - 1;
}
if (nbBlocks > Constants.DEFAULT_MAX_GET_INVENTORIES)
{
nbBlocks = Constants.DEFAULT_MAX_GET_INVENTORIES;
}
var blocks = blockChain.GetLastBlocks(nbBlocks);
var inventories = new List <Inventory>();
foreach (var block in blocks)
{
inventories.Add(new Inventory(InventoryTypes.MSG_BLOCK, block.GetHashHeader()));
}
return(new InventoryMessage(inventories, msg.MessageHeader.Network));
}
return(null);
}