public async Task <DomainEventResult> AppendAsync(
IDomainEvent @event,
CancellationToken token = default)
{
if ([email protected]())
{
return(DomainEventResult.StorageFailed(@event.Id, $"The domain event: [{@event.Print()}] cannot be stored mysql state backend."));
}
var domainEventRecord = DomainEventRecordPortAdapter.ToDomainEventRecord(@event, _binarySerializer);
var parameters = DbParameterProvider.ReflectionParameters(domainEventRecord);
var tables = _options.Tables.DomainEventOptions;
var insertDomainEventIndexSql = $"INSERT INTO `{tables.DomainEventIndices}`(`DomainCommandId`,`DomainCommandType`,`DomainCommandVersion`,`AggregateRootId`,`AggregateRootType`,`AggregateRootVersion`,`AggregateRootGeneration`,`DomainEventId`,`DomainEventType`,`DomainEventVersion`,`DomainEventPayloadBytes`,`CreatedTimestamp`) VALUES(@DomainCommandId,@DomainCommandType,@DomainCommandVersion,@AggregateRootId,@AggregateRootType,@AggregateRootVersion,@AggregateRootGeneration,@DomainEventId,@DomainEventType,@DomainEventVersion,@DomainEventPayloadBytes,@CreatedTimestamp)";
var insertDomainEventSql = $"INSERT INTO `{tables.DomainEvents}`(`DomainEventId`,`Payload`) VALUES (@DomainEventId,@Payload)";
var maxNumErrorTries = 3;
var maxExecutionTime = TimeSpan.FromSeconds(3);
var expectedRows = 2;
bool ErrorFilter(Exception exc, int attempt)
{
if (exc is MySqlException inner &&
inner.HasDuplicateEntry())
{
_logger.LogWarning($"{domainEventRecord.AggregateRootType}: [Ignored]find duplicated domain event from mysql state backend：{inner.Message}.");
return(false);
}
_logger.LogError($"Append domain event has unknown exception: {LogFormatter.PrintException(exc)}.");
return(true);
}
var affectedRows = await AsyncExecutorWithRetries.ExecuteWithRetriesAsync(async attempt =>
{
return(await _db.ExecuteAsync(
$"{insertDomainEventIndexSql};{insertDomainEventSql};",
command => command.Parameters.AddRange(parameters),
token));
}, maxNumErrorTries, ErrorFilter, maxExecutionTime).ConfigureAwait(false);
if (affectedRows != expectedRows)
{
return(DomainEventResult.StorageFailed(@event.Id,
$"The affected rows returned MySql state backend is incorrect, expected: {expectedRows}, actual: {affectedRows}."));
}
return(DomainEventResult.StorageSucceed(@event.Id));
}
public async Task <IEnumerable <IDomainEvent> > GetEventStreamAsync(
string aggregateRootId,
long startOffset = 0,
long endOffset = long.MaxValue,
CancellationToken token = default)
{
PreConditions.NotNullOrEmpty(aggregateRootId, nameof(aggregateRootId));
PreConditions.Nonnegative(startOffset, nameof(startOffset));
var tables = _options.Tables.DomainEventOptions;
var sql = $"SELECT d.`DomainCommandId`,d.`DomainCommandType`,d.`DomainCommandVersion`,d.`AggregateRootId`,d.`AggregateRootType`,d.`AggregateRootVersion`,d.`AggregateRootGeneration`,d.`DomainEventId`,d.`DomainEventType`,d.`DomainEventVersion`,d.`CreatedTimestamp`, p.`Payload` FROM `{tables.DomainEventIndices}` d INNER JOIN `{tables.DomainEvents}` p ON d.`DomainEventId`=p.`DomainEventId` WHERE d.`AggregateRootId`=@AggregateRootId AND d.AggregateRootVersion>=@StartOffset AND d.AggregateRootVersion<@EndOffset";
var records = await _db.ReadAsync <DomainEventRecord>(sql, new
{
AggregateRootId = aggregateRootId,
StartOffset = startOffset,
EndOffset = endOffset
}, token);
if (records.IsEmpty())
{
return(null);
}
var domainEvents = new List <IDomainEvent>();
foreach (var record in records)
{
var domainEvent = DomainEventRecordPortAdapter.ToDomainEvent(record, _typeResolver, _binarySerializer);
if (!domainEvent.IsValid())
{
_logger.LogCritical($"Found illegal domain event from mysql state backend: {domainEvent.Print()}.");
continue;
}
domainEvents.Add(domainEvent);
}
return(domainEvents);
}