/// <summary>
/// Check the validity of an event (i.e. all required fields are set).
/// </summary>
/// <param name="event">Event to check</param>
/// <exception cref="DomainEventIncompleteException">The domain event is incomplete/invalid and cannot be added to the event store.</exception>
private void CheckValidity(IDomainEvent @event)
{
if ([email protected]())
{
throw new DomainEventIncompleteException();
}
}
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 virtual void Apply(IDomainEvent e)
{
var eventType = e.GetType();
var castedEvent = Convert.ChangeType(e, eventType);
var bindingFlags = BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance;
var methods = GetType().GetMethods(bindingFlags)
.Where(x => x.GetParameters().Count() > 0)
.Where(x => x.Name.Contains("Apply"))
.Where(x => x.GetParameters()[0].ParameterType == eventType)
.ToList();
if (methods.Count() <= 0)
throw new ArgumentException(string.Format("Event '{0}' cannot be processed by this aggregate", e.GetType()));
if (e.IsValid())
methods.First().Invoke(this, bindingFlags, null, new[] {castedEvent}, null);
}
