public IndexBuilderService(RPCClient rpc, BlockNotifier blockNotifier, string indexFilePath, string bech32UtxoSetFilePath)
{
RpcClient = Guard.NotNull(nameof(rpc), rpc);
BlockNotifier = Guard.NotNull(nameof(blockNotifier), blockNotifier);
IndexFilePath = Guard.NotNullOrEmptyOrWhitespace(nameof(indexFilePath), indexFilePath);
Bech32UtxoSetFilePath = Guard.NotNullOrEmptyOrWhitespace(nameof(bech32UtxoSetFilePath), bech32UtxoSetFilePath);
Bech32UtxoSet = new Dictionary<OutPoint, UtxoEntry>();
Bech32UtxoSetHistory = new List<ActionHistoryHelper>(capacity: 100);
Index = new List<FilterModel>();
IndexLock = new AsyncLock();
StartingHeight = SmartHeader.GetStartingHeader(RpcClient.Network).Height;
_running = 0;
IoHelpers.EnsureContainingDirectoryExists(IndexFilePath);
if (File.Exists(IndexFilePath))
{
if (RpcClient.Network == Network.RegTest)
{
File.Delete(IndexFilePath); // RegTest is not a global ledger, better to delete it.
}
else
{
foreach (var line in File.ReadAllLines(IndexFilePath))
{
var filter = FilterModel.FromLine(line);
Index.Add(filter);
}
}
}
IoHelpers.EnsureContainingDirectoryExists(bech32UtxoSetFilePath);
if (File.Exists(bech32UtxoSetFilePath))
{
if (RpcClient.Network == Network.RegTest)
{
File.Delete(bech32UtxoSetFilePath); // RegTest is not a global ledger, better to delete it.
}
else
{
foreach (var line in File.ReadAllLines(Bech32UtxoSetFilePath))
{
var parts = line.Split(':');
var txHash = new uint256(parts[0]);
var nIn = int.Parse(parts[1]);
var script = new Script(ByteHelpers.FromHex(parts[2]), true);
OutPoint outPoint = new OutPoint(txHash, nIn);
var utxoEntry = new UtxoEntry(outPoint, script);
Bech32UtxoSet.Add(outPoint, utxoEntry);
}
}
}
BlockNotifier.OnBlock += BlockNotifier_OnBlock;
}
public void Synchronize()
{
Task.Run(async () =>
{
try
{
if (Interlocked.Read(ref _runner) >= 2)
{
return;
}
Interlocked.Increment(ref _runner);
while (Interlocked.Read(ref _runner) != 1)
{
await Task.Delay(100);
}
if (Interlocked.Read(ref _running) >= 2)
{
return;
}
try
{
Interlocked.Exchange(ref _running, 1);
var isImmature = false; // The last 100 blocks are reorgable. (Assume it is mature at first.)
SyncInfo syncInfo = null;
while (IsRunning)
{
try
{
// If we did not yet initialized syncInfo, do so.
if (syncInfo is null)
{
syncInfo = await GetSyncInfoAsync();
}
uint heightToRequest = StartingHeight;
uint256 currentHash = null;
using (await IndexLock.LockAsync())
{
if (Index.Count != 0)
{
var lastIndex = Index.Last();
heightToRequest = lastIndex.Header.Height + 1;
currentHash = lastIndex.Header.BlockHash;
}
}
// If not synchronized or already 5 min passed since last update, get the latest blockchain info.
if (!syncInfo.IsCoreSynchornized || syncInfo.BlockchainInfoUpdated - DateTimeOffset.UtcNow > TimeSpan.FromMinutes(5))
{
syncInfo = await GetSyncInfoAsync();
}
if (syncInfo.BlockCount - heightToRequest <= 100)
{
// Both Wasabi and our Core node is in sync. Start doing stuff through P2P from now on.
if (syncInfo.IsCoreSynchornized && syncInfo.BlockCount == heightToRequest - 1)
{
syncInfo = await GetSyncInfoAsync();
// Double it to make sure not to accidentally miss any notification.
if (syncInfo.IsCoreSynchornized && syncInfo.BlockCount == heightToRequest - 1)
{
// Mark the process notstarted, so it can be started again and finally block can mark it is stopped.
Interlocked.Exchange(ref _running, 0);
return;
}
}
// Mark the synchronizing process is working with immature blocks from now on.
isImmature = true;
}
Block block = await RpcClient.GetBlockAsync(heightToRequest);
// Reorg check, except if we're requesting the starting height, because then the "currentHash" wouldn't exist.
if (heightToRequest != StartingHeight && currentHash != block.Header.HashPrevBlock)
{
// Reorg can happen only when immature. (If it'd not be immature, that'd be a huge issue.)
if (isImmature)
{
await ReorgOneAsync();
}
else
{
Logger.LogCritical("This is something serious! Over 100 block reorg is noticed! We cannot handle that!");
}
// Skip the current block.
continue;
}
if (isImmature)
{
PrepareBech32UtxoSetHistory();
}
var scripts = new HashSet<Script>();
foreach (var tx in block.Transactions)
{
// If stop was requested return.
// Because this tx iteration can take even minutes
// It does not need to be accessed with a thread safe fashion with Interlocked through IsRunning, this may have some performance benefit
if (_running != 1)
{
return;
}
for (int i = 0; i < tx.Outputs.Count; i++)
{
var output = tx.Outputs[i];
if (output.ScriptPubKey.IsScriptType(ScriptType.P2WPKH))
{
var outpoint = new OutPoint(tx.GetHash(), i);
var utxoEntry = new UtxoEntry(outpoint, output.ScriptPubKey);
Bech32UtxoSet.Add(outpoint, utxoEntry);
if (isImmature)
{
Bech32UtxoSetHistory.Last().StoreAction(Operation.Add, outpoint, output.ScriptPubKey);
}
scripts.Add(output.ScriptPubKey);
}
}
foreach (var input in tx.Inputs)
{
OutPoint prevOut = input.PrevOut;
if (Bech32UtxoSet.TryGetValue(prevOut, out UtxoEntry foundUtxoEntry))
{
var foundScript = foundUtxoEntry.Script;
Bech32UtxoSet.Remove(prevOut);
if (isImmature)
{
Bech32UtxoSetHistory.Last().StoreAction(Operation.Remove, prevOut, foundScript);
}
scripts.Add(foundScript);
}
}
}
GolombRiceFilter filter;
if (scripts.Any())
{
filter = new GolombRiceFilterBuilder()
.SetKey(block.GetHash())
.SetP(20)
.SetM(1 << 20)
.AddEntries(scripts.Select(x => x.ToCompressedBytes()))
.Build();
}
else
{
// We cannot have empty filters, because there was a bug in GolombRiceFilterBuilder that evaluates empty filters to true.
// And this must be fixed in a backwards compatible way, so we create a fake filter with a random scp instead.
filter = CreateDummyEmptyFilter(block.GetHash());
}
var smartHeader = new SmartHeader(block.GetHash(), block.Header.HashPrevBlock, heightToRequest, block.Header.BlockTime);
var filterModel = new FilterModel(smartHeader, filter);
await File.AppendAllLinesAsync(IndexFilePath, new[] { filterModel.ToLine() });
using (await IndexLock.LockAsync())
{
Index.Add(filterModel);
}
if (File.Exists(Bech32UtxoSetFilePath))
{
File.Delete(Bech32UtxoSetFilePath);
}
var bech32UtxoSetLines = Bech32UtxoSet.Select(entry => entry.Value.Line);
// Keep it sync unless you fix the performance issue with async.
File.WriteAllLines(Bech32UtxoSetFilePath, bech32UtxoSetLines);
// If not close to the tip, just log debug.
// Use height.Value instead of simply height, because it cannot be negative height.
if (syncInfo.BlockCount - heightToRequest <= 3 || heightToRequest % 100 == 0)
{
Logger.LogInfo($"Created filter for block: {heightToRequest}.");
}
else
{
Logger.LogDebug($"Created filter for block: {heightToRequest}.");
}
}
catch (Exception ex)
{
Logger.LogDebug(ex);
}
}
}
finally
{
Interlocked.CompareExchange(ref _running, 3, 2); // If IsStopping, make it stopped.
Interlocked.Decrement(ref _runner);
}
}
catch (Exception ex)
{
Logger.LogError($"Synchronization attempt failed to start: {ex}");
}
});
}