private async Task MessageHandler(ProcessMessageEventArgs args)
{
try
{
_logger.LogInformation($"client '{_systemInfo.ClientId}' received message '{args.Message.MessageId}'. Processing...");
var message = _messageParser.Resolve <TM>(args.Message.Body);
await _messageProcessor.ProcessAsync((dynamic)message, args.CancellationToken);
await args.CompleteMessageAsync(args.Message).ConfigureAwait(false);
}
catch (Exception ex)
{
_logger.LogError(ex, $"an error has occurred while processing message '{args.Message.MessageId}': {ex.Message}");
if (args.Message.DeliveryCount > 3)
{
await args.DeadLetterMessageAsync(args.Message).ConfigureAwait(false);
}
else
{
await args.AbandonMessageAsync(args.Message).ConfigureAwait(false);
}
}
}
private async Task OnMessageReceivedAsync(object sender, BasicDeliverEventArgs eventArgs)
{
var consumer = sender as IBasicConsumer;
var channel = consumer?.Model ?? _channel;
IMessage message;
try
{
message = _messageParser.Resolve(eventArgs.BasicProperties, eventArgs.Body);
}
catch (Exception ex)
{
_logger.LogError(ex, "an exception has occured while decoding queue message from Exchange '{ExchangeName}', message cannot be processed. Error: {ExceptionMessage}",
eventArgs.Exchange, ex.Message);
channel.BasicReject(eventArgs.DeliveryTag, requeue: false);
return;
}
_logger.LogDebug("received message '{MessageId}' from Exchange '{ExchangeName}', Queue '{QueueName}'. Processing...",
message.Id, _queueReferences.ExchangeName, _queueReferences.QueueName);
try
{
//TODO: provide valid cancellation token
await _messageProcessor.ProcessAsync((dynamic)message, CancellationToken.None);
channel.BasicAck(eventArgs.DeliveryTag, multiple: false);
}
catch (Exception ex)
{
var errorMsg = eventArgs.Redelivered ? "a fatal error has occurred while processing Message '{MessageId}' from Exchange '{ExchangeName}' : {ExceptionMessage} . Rejecting..." :
"an error has occurred while processing Message '{MessageId}' from Exchange '{ExchangeName}' : {ExceptionMessage} . Nacking...";
_logger.LogWarning(ex, errorMsg, message.Id, _queueReferences.ExchangeName, ex.Message);
if (eventArgs.Redelivered)
{
channel.BasicReject(eventArgs.DeliveryTag, requeue: false);
}
else
{
channel.BasicNack(eventArgs.DeliveryTag, multiple: false, requeue: true);
}
}
}
