private async Task ProcessBatchesAsync(CancellationToken cancellationToken)
{
while (!cancellationToken.IsCancellationRequested)
{
_logger.LogInformation($"Sleeping for {_configuration.BatchFrequencyInMilliseconds} ms.".AddTimestamp());
await Task.Delay(_configuration.BatchFrequencyInMilliseconds, cancellationToken);
List <Bet> batch;
ulong deliveryTag;
lock (_betsBatch)
{
batch = _betsBatch;
_betsBatch = new List <Bet>();
deliveryTag = _lastDeliveryTag;
}
if (!batch.Any())
{
_logger.LogInformation("No batch to process.".AddTimestamp());
continue;
}
_logger.LogInformation($"Processing batch of {batch.Count} bets.".AddTimestamp());
var stakeIds = batch.Select(b => b.StakeId);
var betsByStakeIds = batch.GroupBy(b => b.StakeId).ToDictionary(g => g.Key, g => g.Count());
using (var dbContext = new BetsDbContext(_configuration.ConnectionString))
using (var transaction = await dbContext.Database.BeginTransactionAsync(IsolationLevel.RepeatableRead, cancellationToken))
{
var matches = await dbContext.Matches.Include(m => m.Stakes).Where(m => m.Stakes.Any(s => stakeIds.Contains(s.Id)))
.ToListAsync(cancellationToken);
_logger.LogInformation($"Got {matches.Count} matches".AddTimestamp());
var newStakes = matches.SelectMany(m => m.Stakes.Where(s => s.IsBettable).Select(s => CalculateNewStake(s, m, betsByStakeIds))).ToList();
foreach (var oldStake in matches.SelectMany(m => m.Stakes.Where(s => s.IsBettable)))
{
oldStake.IsBettable = false;
}
_logger.LogInformation("Calculated stakes.");
dbContext.Stakes.AddRange(newStakes);
await dbContext.SaveChangesAsync(cancellationToken);
transaction.Commit();
}
EventConsumer.Ack(deliveryTag);
}
}
