public bool IsChainUpToDate(out NodeChainHeight longestChainNode)
{
longestChainNode = null;
bool isUpToDate = false;
int margin = 1;
Node longestNode = null;
int longestChain = GetLongestChain(out longestNode);
if (longestChain == -1)
{
throw new ValidationException(ResponseCodes.NoChainExistOnNetwork, "Failed to sync chain: " + ResponseMessages.NoChainExistOnNetwork);
}
//Compare with self height
ViewerServices viewerServices = new ViewerServices();
int localHeight = viewerServices.GetChainHeight();
if (longestChain > (localHeight + margin))
{
isUpToDate = false;
}
else
{
isUpToDate = true;
}
longestChainNode = new NodeChainHeight();
longestChainNode.Address = longestNode.ServerAddress;
longestChainNode.ChainHeight = longestChain;
return(isUpToDate);
}
public void SyncChain(NodeChainHeight longestChainNode)
{
ApplicationLog.Info("Downloading chain.");
ApplicationState.ConsensusState = ConsensusStates.SyncingChain;
ViewerServices viewerServices = new ViewerServices();
int localHeight = viewerServices.GetChainHeight();
if (localHeight < 0)
{
localHeight = 0;
}
//TODO: Future enhancement to download from different nodes in parellel
int currentHeight = localHeight;
int lastHeight = longestChainNode.ChainHeight;
while (currentHeight <= lastHeight)
{
var blocks = GetBlocks(longestChainNode.Address, currentHeight, currentHeight + 10);
foreach (var block in blocks)
{
AddBlockToChain(block);
currentHeight++;
}
}
}
public async void NextEpoch()
{
try
{
ApplicationLog.Info("Beginning new epoch iteration");
ApplicationState.ConsensusState = ConsensusStates.BeginningEpoch;
ApplicationState.CurrentSpeaker = null;
NodeChainHeight longestChainNode = null;
if (ApplicationState.DisconnectedNodes.Count > 0)
{
RemoveDisconnectedNodes();
//TODO: subsequent epoch can retrieve network nodes from other nodes instead of from seed
RetrieveNetworkNodes();
}
if (IsChainUpToDate(out longestChainNode))
{
ApplicationState.IsChainUpToDate = true;
ApplicationState.LiveEpochCount++;
SelectSpeaker();
}
else
{
ApplicationState.IsChainUpToDate = false;
SyncChain(longestChainNode);
ApplicationState.LiveEpochCount = 0;
ApplicationState.PendingRecords.Clear();
RegisterSelfOnNetwork(ApplicationState.Node.WalletAddress, ApplicationState.Node.Signature, false);
NextEpoch();
}
}
catch (Exception ex)
{
ApplicationLog.Exception(ex);
ApplicationLog.Info("Retry in 30 seconds.");
await Task.Delay(30 * 1000);
NextEpoch();
}
}
