public byte[] this[byte[] key]
{
get
{
lock (_diffLock)
{
RequiredPeerDifficulty = UInt256.Max(RequiredPeerDifficulty, BeamSyncContext.MinimumDifficulty.Value);
}
// it is not possible for the item to be requested from the DB and missing in the DB unless the DB is corrupted
// if it is missing in the MemDb then it must exist somewhere on the web (unless the block is corrupted / invalid)
// we grab the node from the web through requests
// if the block is invalid then we will be timing out for a long time
// in such case it would be good to have some gossip about corrupted blocks
// but such gossip would be cheap
// if we keep timing out then we would finally reject the block (but only shelve it instead of marking invalid)
bool wasInDb = true;
while (true)
{
if (BeamSyncContext.Cancelled.Value.IsCancellationRequested)
{
throw new TaskCanceledException("Beam Sync task cancelled by a new block.");
}
if (_isDisposed)
{
throw new ObjectDisposedException("Beam Sync DB disposed");
}
// shall I leave test logic forever?
if (BeamSyncContext.LoopIterationsToFailInTest.Value != null)
{
int?currentValue = BeamSyncContext.LoopIterationsToFailInTest.Value--;
if (currentValue == 0)
{
throw new Exception();
}
}
var fromMem = _db[key];
if (fromMem == null)
{
if (Bytes.AreEqual(key, Keccak.Zero.Bytes))
{
// we store sync progress data at Keccak.Zero;
return(null);
}
TimeSpan expiry = _contextExpiryTimeSpan;
if (BeamSyncContext.Description.Value?.Contains("preProcess") ?? false)
{
expiry = _preProcessExpiryTimeSpan;
}
if (DateTime.UtcNow - (BeamSyncContext.LastFetchUtc.Value ?? DateTime.UtcNow) > expiry)
{
string message = $"Beam sync request {BeamSyncContext.Description.Value} with last update on {BeamSyncContext.LastFetchUtc.Value:hh:mm:ss.fff} has expired";
if (_logger.IsDebug)
{
_logger.Debug(message);
}
throw new BeamSyncException(message);
}
wasInDb = false;
// _logger.Info($"BEAM SYNC Asking for {key.ToHexString()} - resolved keys so far {_resolvedKeysCount}");
int count;
lock (_requestedNodes)
{
_requestedNodes.Add(new Keccak(key));
count = _requestedNodes.Count;
}
// _logger.Error($"Requested {key.ToHexString()}");
NeedMoreData?.Invoke(this, EventArgs.Empty);
_autoReset.WaitOne(50);
}
else
{
if (!wasInDb)
{
BeamSyncContext.ResolvedInContext.Value++;
Interlocked.Increment(ref _resolvedKeysCount);
// if (_logger.IsInfo) _logger.Info($"{_description} Resolved key {key.ToHexString()} of context {BeamSyncContext.Description.Value} - resolved ctx {BeamSyncContext.ResolvedInContext.Value} | total {_resolvedKeysCount}");
}
BeamSyncContext.LastFetchUtc.Value = DateTime.UtcNow;
return(fromMem);
}
}
}
set => _db[key] = value;
private void DataConsumerOnNeedMoreData(object sender, EventArgs e)
{
NeedMoreData?.Invoke(this, EventArgs.Empty);
}
