public void ReceiveBlock(IBlockchainPeer sender, IBlock block)
{
try {
// TODO: full block check
// TODO: implement remembering the last block of the main chain for fork verification
// TODO: implement a pool of orphan blocks in case of receiving a block for which its parent block was not previously received
//fChain.AddBlock();
// TODO: what should be the mechanism of protection against flooding here?!
//BroadcastBlock(block);
} catch {
// if !block.IsCorrect(), then do nothing
}
}
/// <summary>
/// The function accepts a pending transaction from another node.
/// </summary>
public void ReceiveTransaction(IBlockchainPeer sender, Transaction transaction)
{
try {
// TODO: check that the transaction is not in the pool (if received earlier from another node and has not yet been processed)
// or blockchain (if an old, long-processed transaction has been received)
// TODO: transaction validation should take into account the scenario when the receive order is violated and the transaction
// tries to modify data not yet added by a transaction that is not in the pool (leave pending)
if (VerifyTransactions(transaction))
{
AddPendingTransaction(transaction);
// TODO: what should be the mechanism of protection against flooding here?!
//BroadcastTransaction(transaction);
}
} catch {
// if !trx.IsCorrect(), then do nothing
}
}
/// <summary>
/// Replenishment of the blockchain with a list of blocks received from a peer.
/// </summary>
public void ReceiveBlocksResponse(IBlockchainPeer peer, string json)
{
var newBlocks = Helpers.DeserializeBlocks(json);
if (!newBlocks.IsCorrect())
{
throw new MethodResultException("newBlocks", "Error receive block chain. The chain is incorrect.");
}
var lastBlock = fDataProvider.GetLastBlock();
if (lastBlock != null && lastBlock.Index == 0)
{
// A node only has a genesis block
// Therefore, the response will come with the full chain, including the genesis block
fDataProvider.ClearBlocks();
}
foreach (var blk in newBlocks)
{
fDataProvider.AddBlock(blk);
ProcessBlockTransactions(blk);
}
}
/// <summary>
/// Received from the connected peer a response with the characteristics (index, hash) of the last block in the chain.
/// </summary>
public void ReceiveChainStateRequest(IBlockchainPeer peer, long peerLastBlockIndex, string peerLastBlockHash)
{
var lastBlock = fDataProvider.GetLastBlock();
if (lastBlock != null && peerLastBlockIndex < lastBlock.Index)
{
if (peerLastBlockIndex > 0)
{
// The chain has the specified common block?
var peerLastBlock = fDataProvider.FindBlock(peerLastBlockHash);
if (peerLastBlock != null && peerLastBlock.Index == peerLastBlockIndex)
{
var blocks = fDataProvider.GetBlocks(peerLastBlockIndex + 1);
SendBlocks(peer, blocks);
}
}
else
{
// A peer only has a genesis block
var blocks = fDataProvider.GetBlocks(0);
SendBlocks(peer, blocks);
}
}
}
public void SendBlock(IBlockchainPeer peer, IBlock block)
{
}
public void SendTransaction(IBlockchainPeer peer, ITransaction transaction)
{
}
public bool SendBlocks(IBlockchainPeer peer, IList <Block> blocks)
{
return(false);
}
/// <summary>
/// Send connected peers a request for characteristics (index, hash) of the last blocks in their chains.
/// </summary>
private void SendChainStateRequest(IBlockchainPeer peer, long selfLastBlockIndex, string selfLastBlockHash)
{
// dummy
}
