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($"Got {matches.Count} matches".AddTimestamp());
var newStakes = matches.SelectMany(m => m.Stakes.Where(s => s.IsBettable).Select(s => CalculateNewStake(s, m, betsByStakeIds))).ToList();
foreach (var oldStake in matches.SelectMany(m => m.Stakes.Where(s => s.IsBettable)))
{
oldStake.IsBettable = false;
}
_logger.LogInformation("Calculated stakes.");
dbContext.Stakes.AddRange(newStakes);
await dbContext.SaveChangesAsync(cancellationToken);
transaction.Commit();
}
EventConsumer.Ack(deliveryTag);
}
}
public async Task <IActionResult> PutAsync(Bet bet)
{
_logger.LogInformation($"Bet:\n{JsonConvert.SerializeObject(bet)}");
var subject = User.GetSubjectClaim();
if (bet.UserId != subject)
{
_logger.LogError($"Unauthorized claim {subject} for userId = {bet.UserId}.");
return(Unauthorized());
}
var stake = await _betsDbContext.Stakes
.Include(s => s.Match)
.SingleOrDefaultAsync(s => s.Id == bet.StakeId);
if (stake == null)
{
return(BadRequest($"Specified stake ${bet.StakeId} does not exist."));
}
if (stake.Match.IsFinished)
{
return(BadRequest($"Match ${stake.MatchId} already finished."));
}
var account = await _betsDbContext.Accounts.SingleOrDefaultAsync(a => a.UserId == bet.UserId);
if (account != null && account.Balance < bet.Amount)
{
return(BadRequest($"Insufficient funds."));
}
_betsDbContext.Bets.Add(bet);
_betEventProducer.PublishNewBet(bet);
await _betsDbContext.SaveChangesAsync();
return(Ok());
}
public async Task Save()
{
await _context.SaveChangesAsync();
}
