private bool TryGetRequest(ConcurrentQueueingConsumer consumer, out HttpRequestPacket request, out MessageDispatch dispatch)
{
request = null;
dispatch = null;
BasicDeliverEventArgs item;
if (!consumer.TryInstantDequeue(out item, throwIfClosed: false))
{
return false;
}
//TODO: Pool MessageDispatch
//Get message
dispatch = new MessageDispatch { Consumer = consumer, Delivery = item };
//Deserialize message
bool wasDeserialized = true;
try
{
request = HttpRequestPacket.Deserialize(item.Body);
}
catch
{
wasDeserialized = false;
}
if (wasDeserialized)
{
//Add/Update Subscriber-Id header
request.Headers[Common.Shared.SUBSCRIBER_ID_HEADER] = this.subscriberIdHeader;
//Add redelivered header if item was redelivered.
if (item.Redelivered)
{
request.Headers[Common.Shared.REDELIVERED_HEADER] = TRUE_STRING_ARRAY;
}
}
//Reject message if deserialization failed.
else if (!wasDeserialized && Settings.AckBehavior != SubscriberAckBehavior.Automatic )
{
consumer.Model.BasicReject(item.DeliveryTag, false);
return false;
}
return true;
}
//TODO: REMOVE LATER: This method is never called because the DirectReplyToStrategy is used when the client decides to use
//the direct reply to feature.
/// <summary>
/// Discovers the Direct reply-to queue name ( https://www.rabbitmq.com/direct-reply-to.html ) by messaging itself.
/// </summary>
private static string DiscoverDirectReplyToQueueName(IModel channel, string indirectReplyToQueueName)
{
DeclareIndirectReplyToQueue(channel, indirectReplyToQueueName);
var receiver = new ConcurrentQueueingConsumer(channel);
var receiverTag = channel.BasicConsume(indirectReplyToQueueName, true, receiver);
channel.BasicPublish(String.Empty, indirectReplyToQueueName, true, new BasicProperties { ReplyTo = RPCStrategyHelpers.DIRECT_REPLY_TO_QUEUENAME_ARG }, new byte[0]);
BasicDeliverEventArgs delivery;
using (ManualResetEventSlim messageReturned = new ManualResetEventSlim())
{
EventHandler<BasicReturnEventArgs> returnHandler = null;
Interlocked.Exchange(ref returnHandler, (a, e) => { messageReturned.Set(); try { receiver.Model.BasicReturn -= returnHandler; } catch { } });
receiver.Model.BasicReturn += returnHandler;
System.Diagnostics.Stopwatch watch = new System.Diagnostics.Stopwatch();
watch.Start();
while (!receiver.TryInstantDequeue(out delivery, throwIfClosed: false))
{
Thread.Sleep(1);
if (watch.Elapsed > TimeSpan.FromSeconds(10) || messageReturned.IsSet)
{
break;
}
}
watch.Stop();
if (!messageReturned.IsSet)
{
try
{
receiver.Model.BasicReturn -= returnHandler;
}
catch { }
}
try
{
channel.BasicCancel(receiverTag);
}
catch { }
}
if (delivery == null)
{
throw new InvalidOperationException("Unable to determine direct reply-to queue name.");
}
var result = delivery.BasicProperties.ReplyTo;
if (result == null || result == RPCStrategyHelpers.DIRECT_REPLY_TO_QUEUENAME_ARG || !result.StartsWith(RPCStrategyHelpers.DIRECT_REPLY_TO_QUEUENAME_ARG))
{
throw new InvalidOperationException("Discovered direct reply-to queue name (" + (result ?? "null") + ") was not in expected format.");
}
return result;
}