private async Task <ISaga> ProcessSagaAsync(
IDomainEvent domainEvent,
ISagaId sagaId,
SagaDetails details,
CancellationToken cancellationToken)
{
try {
_log.Verbose(() => $"Loading saga '{details.SagaType.PrettyPrint()}' with ID '{sagaId}'");
return(await _sagaStore.UpdateAsync <ISaga>(
sagaId,
details,
domainEvent.Metadata.SourceId,
(s, c) => UpdateSagaAsync(s, domainEvent, details, c),
cancellationToken)
.ConfigureAwait(false));
} catch (Exception e) {
var handled = await _sagaErrorHandler.HandleAsync(
sagaId,
details,
e,
cancellationToken)
.ConfigureAwait(false);
if (handled)
{
return(null);
}
_log.Error(e,
$"Failed to process domain event '{domainEvent.EventType}' for saga '{details.SagaType.PrettyPrint()}'");
throw;
}
}
public async Task <TSaga> UpdateAsync <TSaga>(
ISagaId sagaId,
SagaDetails sagaDetails,
ISourceId sourceId,
Func <TSaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken)
where TSaga : ISaga
{
var saga = default(TSaga);
var storeAggregateSagaAsync = await GetUpdateAsync(
sagaDetails.SagaType,
cancellationToken)
.ConfigureAwait(false);
var domainEvents = await storeAggregateSagaAsync(
sagaId,
sourceId,
async (s, c) => {
var specificSaga = (TSaga)s;
await updateSaga(specificSaga, c).ConfigureAwait(false);
saga = specificSaga;
},
cancellationToken)
.ConfigureAwait(false);
return(domainEvents.Any()
? saga
: default(TSaga));
}
public override async Task <ISaga> UpdateAsync(
ISagaId sagaId,
Type sagaType,
ISourceId sourceId,
Func <ISaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken)
{
var commandBus = _serviceProvider.GetRequiredService <ICommandBus>();
ISaga saga;
using (await _asyncLock.WaitAsync(cancellationToken).ConfigureAwait(false))
{
_hasUpdateBeenCalled = true;
if (!_sagas.TryGetValue(sagaId, out var obj))
{
obj = Activator.CreateInstance(sagaType, sagaId);
_sagas[sagaId] = obj;
}
saga = (ISaga)obj;
await updateSaga(saga, cancellationToken).ConfigureAwait(false);
}
await saga.PublishAsync(commandBus, cancellationToken).ConfigureAwait(false);
return(saga);
}
public async Task <TSaga> UpdateAsync <TSaga>(
ISagaId sagaId,
SagaDetails sagaDetails,
ISourceId sourceId,
Func <TSaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken)
where TSaga : ISaga
{
using (await _asyncLock.WaitAsync(cancellationToken).ConfigureAwait(false))
{
_hasUpdateBeenCalled = true;
if (!_sagas.TryGetValue(sagaId, out var obj))
{
obj = Activator.CreateInstance(sagaDetails.SagaType, sagaId);
_sagas[sagaId] = obj;
}
var saga = (TSaga)obj;
await updateSaga(saga, cancellationToken).ConfigureAwait(false);
return(saga);
}
}
public Task <bool> HandleAsync(
ISagaId sagaId,
SagaDetails sagaDetails,
Exception exception,
CancellationToken cancellationToken)
{
// The default handler cannot handle anything!
return(Task.FromResult(false));
}
public async Task <TSaga> UpdateAsync <TSaga>(
ISagaId sagaId,
ISourceId sourceId,
Func <TSaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken)
where TSaga : ISaga
{
return((TSaga) await UpdateAsync(
sagaId,
typeof(TSaga),
sourceId,
(s, c) => updateSaga((TSaga)s, c),
cancellationToken)
.ConfigureAwait(false));
}
private async Task ProcessSagaAsync(
IDomainEvent domainEvent,
ISagaId sagaId,
SagaDetails details,
CancellationToken cancellationToken)
{
try
{
_logger.LogTrace(
"Loading saga {SagaType} with ID {Id}",
details.SagaType.PrettyPrint(),
sagaId);
await _sagaStore.UpdateAsync(
sagaId,
details.SagaType,
domainEvent.Metadata.EventId,
(s, c) => UpdateSagaAsync(s, domainEvent, details, c),
cancellationToken)
.ConfigureAwait(false);
}
catch (Exception e)
{
var handled = await _sagaErrorHandler.HandleAsync(
sagaId,
details,
e,
cancellationToken)
.ConfigureAwait(false);
if (handled)
{
return;
}
_logger.LogError(
"Failed to process domain event {DomainEventType} for saga {SagaType}",
domainEvent.EventType,
details.SagaType.PrettyPrint());
throw;
}
}
public override async Task <ISaga> UpdateAsync(
ISagaId sagaId,
Type sagaType,
ISourceId sourceId,
Func <ISaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken)
{
var saga = null as ISaga;
var storeAggregateSagaAsync = await GetUpdateAsync(
sagaType,
cancellationToken)
.ConfigureAwait(false);
var domainEvents = await storeAggregateSagaAsync(
this,
sagaId,
sourceId,
async (s, c) =>
{
await updateSaga(s, c).ConfigureAwait(false);
saga = s;
},
cancellationToken)
.ConfigureAwait(false);
if (!domainEvents.Any())
{
return(null);
}
var commandBus = _resolver.Resolve <ICommandBus>();
await saga.PublishAsync(commandBus, cancellationToken).ConfigureAwait(false);
return(saga);
}
private async Task ProcessSagaAsync(
IDomainEvent domainEvent,
ISagaId sagaId,
SagaDetails details,
CancellationToken cancellationToken)
{
try
{
_log.Verbose(() => $"Loading saga '{details.SagaType.PrettyPrint()}' with ID '{sagaId}'");
await _sagaStore.UpdateAsync(
sagaId,
details.SagaType,
domainEvent.Metadata.EventId,
(s, c) => UpdateSagaAsync(s, domainEvent, details, c),
cancellationToken)
.ConfigureAwait(false);
}
catch (Exception e)
{
// Search for a specific SagaErrorHandler<Saga> based on saga type
ISagaErrorHandler specificSagaErrorHandler = _sagaErrorHandlerFactory(details.SagaType);
bool handled = specificSagaErrorHandler != null ?
await specificSagaErrorHandler.HandleAsync(sagaId, details, e, cancellationToken).ConfigureAwait(false) :
await _sagaErrorHandler.HandleAsync(sagaId, details, e, cancellationToken).ConfigureAwait(false);
if (handled)
{
return;
}
_log.Error(e, $"Failed to process domain event '{domainEvent.EventType}' for saga '{details.SagaType.PrettyPrint()}'");
throw;
}
}
public override async Task <ISaga> UpdateAsync(
ISagaId sagaId,
Type sagaType,
ISourceId sourceId,
Func <ISaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken)
{
var saga = null as ISaga;
var storeAggregateSagaAsync = await GetUpdateAsync(
sagaType,
cancellationToken)
.ConfigureAwait(false);
await storeAggregateSagaAsync(
this,
sagaId,
sourceId,
async (s, c) =>
{
await updateSaga(s, c).ConfigureAwait(false);
saga = s;
},
cancellationToken)
.ConfigureAwait(false);
if (saga is null)
{
return(null);
}
var commandBus = _serviceProvider.GetRequiredService <ICommandBus>();
await saga.PublishAsync(commandBus, cancellationToken).ConfigureAwait(false);
return(saga);
}
public abstract Task <ISaga> UpdateAsync(
ISagaId sagaId,
Type sagaType,
ISourceId sourceId,
Func <ISaga, CancellationToken, Task> updateSaga,
CancellationToken cancellationToken);
public Task <bool> HandleAsync(ISagaId sagaId, SagaDetails sagaDetails, Exception exception,
CancellationToken cancellationToken)
{
return(Task.FromResult(true));
}