public async Task Invoke(IInvokeHandlerContext context, Func <IInvokeHandlerContext, Task> next)
{
var isTimeoutMessage = IsTimeoutMessage(context.Headers);
var isTimeoutHandler = context.MessageHandler.IsTimeoutHandler;
if (isTimeoutHandler && !isTimeoutMessage)
{
return;
}
if (!isTimeoutHandler && isTimeoutMessage)
{
return;
}
RemoveSagaHeadersIfProcessingAEvent(context);
if (!(context.MessageHandler.Instance is Saga saga))
{
await next(context).ConfigureAwait(false);
return;
}
var currentSagaMetadata = sagaMetadataCollection.Find(context.MessageHandler.Instance.GetType());
if (context.Headers.TryGetValue(Headers.SagaType, out var targetSagaTypeString) && context.Headers.TryGetValue(Headers.SagaId, out var targetSagaId))
{
var targetSagaType = Type.GetType(targetSagaTypeString, false);
if (targetSagaType == null)
{
logger.Warn($"Saga headers indicated that the message was intended for {targetSagaTypeString} but that type isn't available. Will fallback to query persister for a saga instance of type {currentSagaMetadata.SagaType.FullName} and saga id {targetSagaId} instead");
}
else
{
if (!sagaMetadataCollection.TryFind(targetSagaType, out var targetSagaMetaData))
{
logger.Warn($"Saga headers indicated that the message was intended for {targetSagaType.FullName} but no metadata was found for that saga type. Will fallback to query persister for a saga instance of type {currentSagaMetadata.SagaType.FullName} and saga id {targetSagaId} instead");
}
else
{
if (targetSagaMetaData.SagaType != currentSagaMetadata.SagaType)
{
//Message was intended for a different saga so no need to continue with this invocation
return;
}
}
}
}
var sagaInstanceState = new ActiveSagaInstance(saga, currentSagaMetadata, () => DateTimeOffset.UtcNow);
//so that other behaviors can access the saga
context.Extensions.Set(sagaInstanceState);
var loadedEntity = await TryLoadSagaEntity(currentSagaMetadata, context).ConfigureAwait(false);
if (loadedEntity == null)
{
if (IsMessageAllowedToStartTheSaga(context, currentSagaMetadata))
{
context.Extensions.Get <SagaInvocationResult>().SagaFound();
sagaInstanceState.AttachNewEntity(CreateNewSagaEntity(currentSagaMetadata, context));
}
else
{
if (!context.Headers.ContainsKey(Headers.SagaId))
{
var finderDefinition = GetSagaFinder(currentSagaMetadata, context);
if (finderDefinition == null)
{
throw new Exception($"Message type {context.MessageBeingHandled.GetType().Name} is handled by saga {currentSagaMetadata.SagaType.Name}, but the saga does not contain a property mapping or custom saga finder to map the message to saga data. Consider adding a mapping in the saga's {nameof(Saga.ConfigureHowToFindSaga)} method.");
}
}
sagaInstanceState.MarkAsNotFound();
//we don't invoke not found handlers for timeouts
if (isTimeoutMessage)
{
context.Extensions.Get <SagaInvocationResult>().SagaFound();
logger.InfoFormat("No saga found for timeout message {0}, ignoring since the saga has been marked as complete before the timeout fired", context.MessageId);
}
else
{
context.Extensions.Get <SagaInvocationResult>().SagaNotFound();
}
}
}
else
{
context.Extensions.Get <SagaInvocationResult>().SagaFound();
sagaInstanceState.AttachExistingEntity(loadedEntity);
}
await next(context).ConfigureAwait(false);
if (sagaInstanceState.NotFound)
{
return;
}
if (saga.Completed)
{
if (!sagaInstanceState.IsNew)
{
await sagaPersister.Complete(saga.Entity, context.SynchronizedStorageSession, context.Extensions, context.CancellationToken).ConfigureAwait(false);
}
logger.DebugFormat("Saga: '{0}' with Id: '{1}' has completed.", sagaInstanceState.Metadata.Name, saga.Entity.Id);
sagaInstanceState.Completed();
}
else
{
sagaInstanceState.ValidateChanges();
if (sagaInstanceState.IsNew)
{
var sagaCorrelationProperty = SagaCorrelationProperty.None;
if (sagaInstanceState.TryGetCorrelationProperty(out var correlationProperty))
{
sagaCorrelationProperty = new SagaCorrelationProperty(correlationProperty.PropertyInfo.Name, correlationProperty.PropertyInfo.GetValue(sagaInstanceState.Instance.Entity));
}
await sagaPersister.Save(saga.Entity, sagaCorrelationProperty, context.SynchronizedStorageSession, context.Extensions, context.CancellationToken).ConfigureAwait(false);
}
else
{
await sagaPersister.Update(saga.Entity, context.SynchronizedStorageSession, context.Extensions, context.CancellationToken).ConfigureAwait(false);
}
sagaInstanceState.Updated();
}
}
public async Task Invoke(IInvokeHandlerContext context, Func <IInvokeHandlerContext, Task> next)
{
var isTimeoutMessage = IsTimeoutMessage(context.Headers);
var isTimeoutHandler = context.MessageHandler.IsTimeoutHandler;
if (isTimeoutHandler && !isTimeoutMessage)
{
return;
}
if (!isTimeoutHandler && isTimeoutMessage)
{
return;
}
currentContext = context;
RemoveSagaHeadersIfProcessingAEvent(context);
var saga = context.MessageHandler.Instance as Saga;
if (saga == null)
{
await next(context).ConfigureAwait(false);
return;
}
var sagaMetadata = sagaMetadataCollection.Find(context.MessageHandler.Instance.GetType());
var sagaInstanceState = new ActiveSagaInstance(saga, sagaMetadata, () => DateTime.UtcNow);
//so that other behaviors can access the saga
context.Extensions.Set(sagaInstanceState);
var loadedEntity = await TryLoadSagaEntity(sagaMetadata, context).ConfigureAwait(false);
if (loadedEntity == null)
{
//if this message are not allowed to start the saga
if (IsMessageAllowedToStartTheSaga(context, sagaMetadata))
{
context.Extensions.Get <SagaInvocationResult>().SagaFound();
sagaInstanceState.AttachNewEntity(CreateNewSagaEntity(sagaMetadata, context));
}
else
{
if (!context.Headers.ContainsKey(Headers.SagaId))
{
var finderDefinition = GetSagaFinder(sagaMetadata, context);
if (finderDefinition == null)
{
throw new Exception($"Message type {context.MessageBeingHandled.GetType().Name} is handled by saga {sagaMetadata.SagaType.Name}, but the saga does not contain a property mapping or custom saga finder to map the message to saga data. Consider adding a mapping in the saga's {nameof(Saga.ConfigureHowToFindSaga)} method.");
}
}
sagaInstanceState.MarkAsNotFound();
//we don't invoke not found handlers for timeouts
if (isTimeoutMessage)
{
context.Extensions.Get <SagaInvocationResult>().SagaFound();
logger.InfoFormat("No saga found for timeout message {0}, ignoring since the saga has been marked as complete before the timeout fired", context.MessageId);
}
else
{
context.Extensions.Get <SagaInvocationResult>().SagaNotFound();
}
}
}
else
{
context.Extensions.Get <SagaInvocationResult>().SagaFound();
sagaInstanceState.AttachExistingEntity(loadedEntity);
}
await next(context).ConfigureAwait(false);
if (sagaInstanceState.NotFound)
{
return;
}
if (saga.Completed)
{
if (!sagaInstanceState.IsNew)
{
await sagaPersister.Complete(saga.Entity, context.SynchronizedStorageSession, context.Extensions).ConfigureAwait(false);
}
if (saga.Entity.Id != Guid.Empty)
{
await timeoutCancellation.CancelDeferredMessages(saga.Entity.Id.ToString(), context).ConfigureAwait(false);
}
logger.DebugFormat("Saga: '{0}' with Id: '{1}' has completed.", sagaInstanceState.Metadata.Name, saga.Entity.Id);
sagaInstanceState.Completed();
}
else
{
sagaInstanceState.ValidateChanges();
if (sagaInstanceState.IsNew)
{
ActiveSagaInstance.CorrelationPropertyInfo correlationProperty;
var sagaCorrelationProperty = SagaCorrelationProperty.None;
if (sagaInstanceState.TryGetCorrelationProperty(out correlationProperty))
{
sagaCorrelationProperty = new SagaCorrelationProperty(correlationProperty.PropertyInfo.Name, correlationProperty.Value);
}
await sagaPersister.Save(saga.Entity, sagaCorrelationProperty, context.SynchronizedStorageSession, context.Extensions).ConfigureAwait(false);
}
else
{
await sagaPersister.Update(saga.Entity, context.SynchronizedStorageSession, context.Extensions).ConfigureAwait(false);
}
sagaInstanceState.Updated();
}
}