public async Task FetchAsync(CancellationToken cancellationToken)
{
_logger.LogInformation("Fetching...");
while (!cancellationToken.IsCancellationRequested)
{
var startDate = DateTime.UtcNow;
var exchanges = await _exchangeRepository.GetAllAsync();
while (!cancellationToken.IsCancellationRequested)
{
_logger.LogInformation("Processing cycle of {count} exchanges started", exchanges.Count());
var exchangeProcessingStartTime = DateTime.UtcNow;
foreach (var exchange in exchanges)
{
var fromBlock =
await _startBlockService.GetAsync(exchange.Id, exchange.BlockNumber);
var recentBlock = await _recentBlockProvider.GetAsync() - _fetcherSettings.RecentBlockReachLimit;
var fetcher = _exchangeEventsFetcherFactory(exchange.Id);
_logger.LogDebug("Fetching events for exchange {exchangeAddress}...", exchange.Id);
while (fromBlock <= recentBlock)
{
var toBlock = Math.Min(fromBlock + _fetcherSettings.BlocksPerIteration, recentBlock);
_logger.LogDebug("Fetching events from {fromBlock} to {toBlock}...", fromBlock, toBlock);
var events = await fetcher.FetchAsync(fromBlock, toBlock);
_logger.LogDebug("{amount} event(s) fetched", events.Count);
await _exchangeEventsProcessor.ProcessAsync(events);
await _startBlockService.UpdateAsync(exchange.Id, toBlock);
fromBlock = toBlock + 1;
}
}
var elapsedMs = (int)(DateTime.UtcNow - exchangeProcessingStartTime).TotalMilliseconds;
if (elapsedMs < _fetcherSettings.DelayMs)
{
await Task.Delay(_fetcherSettings.DelayMs - elapsedMs, cancellationToken);
}
if (DateTime.UtcNow - startDate > TimeSpan.FromMilliseconds(_fetcherSettings.UpdateExchangesIntervalMs))
{
break;
}
}
}
}
private async Task <(ulong FromBlock, ulong ToBlock, bool IsFull)> GetRange(ulong startBlock)
{
var recentBlock = await _recentBlockProvider.GetAsync();
var fromBlock = Math.Min(startBlock, recentBlock - _settings.RecentBlockReachLimit);
var toBlock = Math.Min(startBlock + _settings.BlocksPerIteration,
recentBlock - _settings.RecentBlockReachLimit);
return(fromBlock, toBlock, toBlock - fromBlock == _settings.BlocksPerIteration);
}