private async Task invoke(Envelope envelope, DateTime now)
{
using (var context = new EnvelopeContext(this, envelope, _sender, _delayedJobs))
{
if (envelope.IsDelayed(now))
{
await moveToDelayedMessageQueue(envelope, context);
}
else if (envelope.ResponseId.IsNotEmpty())
{
completeRequestWithRequestedResponse(envelope);
}
else
{
try
{
deserialize(envelope);
}
catch (Exception e)
{
Logger.MessageFailed(envelope, e);
await envelope.Callback.MoveToErrors(new ErrorReport(envelope, e));
return;
}
finally
{
Logger.Received(envelope);
}
await ProcessMessage(envelope, context).ConfigureAwait(false);
}
}
}
public async Task InvokeNow(Envelope envelope)
{
if (envelope.Message == null)
{
throw new ArgumentNullException(nameof(envelope.Message));
}
var handler = _graph.HandlerFor(envelope.Message.GetType());
if (handler == null)
{
throw new ArgumentOutOfRangeException(nameof(envelope), $"No known handler for message type {envelope.Message.GetType().FullName}");
}
using (var context = new EnvelopeContext(this, envelope, _sender, _delayedJobs))
{
try
{
await handler.Handle(context);
// TODO -- what do we do here if this fails? Compensating actions?
await context.SendAllQueuedOutgoingMessages();
}
catch (Exception e)
{
Logger.LogException(e, $"Invocation of {envelope} failed!");
throw;
}
}
}
public async Task ProcessMessage(Envelope envelope, EnvelopeContext context)
{
Logger.ExecutionStarted(envelope);
var handler = _graph.HandlerFor(envelope.Message.GetType());
if (handler == null)
{
await processNoHandlerLogic(envelope, context);
}
else
{
var continuation = await executeChain(handler, context).ConfigureAwait(false);
await continuation.Execute(envelope, context, DateTime.UtcNow).ConfigureAwait(false);
}
}
private async Task <IContinuation> executeChain(MessageHandler handler, EnvelopeContext context)
{
try
{
context.Envelope.Attempts++;
await handler.Handle(context).ConfigureAwait(false);
Logger.ExecutionFinished(context.Envelope);
return(MessageSucceededContinuation.Instance);
}
catch (Exception e)
{
Logger.LogException(e, context.Envelope.CorrelationId, "Failure during message processing execution");
return(context.DetermineContinuation(e, handler.Chain, _graph));
}
}
private async Task moveToDelayedMessageQueue(Envelope envelope, EnvelopeContext context)
{
try
{
envelope.Attempts++;
_delayedJobs.Enqueue(envelope.ExecutionTime.Value, envelope);
await envelope.Callback.MarkSuccessful();
}
catch (Exception e)
{
if (envelope.Attempts >= 3)
{
await envelope.Callback.MarkFailed(e);
context.Logger.LogException(e, envelope.CorrelationId, "Failed to move delayed message to the delayed message queue");
}
var continuation = _graph.DetermineContinuation(envelope, e) ?? new MoveToErrorQueue(e);
await continuation.Execute(envelope, context, DateTime.UtcNow);
}
}
private async Task processNoHandlerLogic(Envelope envelope, EnvelopeContext context)
{
Logger.NoHandlerFor(envelope);
foreach (var handler in _missingHandlers)
{
try
{
await handler.Handle(envelope, context);
}
catch (Exception e)
{
Logger.LogException(e);
}
}
if (envelope.AckRequested)
{
await context.SendAcknowledgement(envelope);
}
}
