public AsyncEventHandler <BasicDeliverEventArgs> Dequeue(CancellationToken cancellationToken,
Func <string, T, Task> callback)
{
cancellationToken.ThrowIfCancellationRequested();
if (callback == null)
{
throw new ArgumentNullException(nameof(callback));
}
var channel = _messagingFactory.Initialize();
return((model, ea) =>
{
cancellationToken.ThrowIfCancellationRequested();
_logger.LogDebug("MESSAGING | RECEIVING NEW MESSAGE");
var body = ea.Body;
var raw = Encoding.UTF8.GetString(body);
var retries = 0;
_logger.LogDebug("MESSAGING | RAW MESSAGE: {raw}");
Policy
.Handle <Exception>()
.Fallback((app) => { },
onFallback: (context, expcetion) =>
{
_logger.LogDebug("MESSAGING | SOMETHING HAPPENED WHEN PROCESSING THE MESSAGE: {ex}",
context.Message);
if (_messagingConfiguration.Retries <= retries)
{
return;
}
channel.BasicNack(ea.DeliveryTag, false, false);
_logger.LogDebug("MESSAGING | MESSAGE HAS BEEN NACKED");
}).Execute(() =>
{
retries = Retries(ea);
_logger.LogDebug("MESSAGING | THIS MESSAGE HAS BEEN PROCESSED { retries } TIMES");
var message = JsonConvert.DeserializeObject <T>(raw);
callback.Invoke(raw, message).ConfigureAwait(false).GetAwaiter().GetResult();
_logger.LogDebug("MESSAGING | MESSAGE WILL BE ACKED");
channel.BasicAck(ea.DeliveryTag, false);
_logger.LogDebug("MESSAGING | MESSAGE HAS BEEN ACKED");
});
return Task.CompletedTask;
});
}
protected override Task ExecuteAsync(CancellationToken stoppingToken)
{
var channel = _messagingFactory.Initialize();
var consumer = new AsyncEventingBasicConsumer(channel);
consumer.Received += _messagingService.Dequeue(stoppingToken, async(raw, message) =>
{
if (message == null)
{
return;
}
using (_logger.BeginScope(Guid.NewGuid().ToString()))
{
try
{
var content = JsonSerializer.Serialize(new PingPongExample()
{
Id = message.Id++,
IsPing = true,
Message = "Ping"
});
_messagingService.Queue(new Message()
{
Exchange = _messagingConfiguration.Publishing.Exchange.Name,
RoutingKey = _messagingConfiguration.Publishing.Routingkey,
Content = content
});
_logger.LogInformation("Send ping from consumer");
}
catch (Exception ex)
{
_logger.LogCritical($"HOST | CRITICAL ERROR: {ex}");
throw;
}
}
});
_tag = channel.BasicConsume(_messagingConfiguration.Consuming.Queue, false, string.Empty, false, false,
null, consumer);
return(Task.CompletedTask);
}