我有一个 ASP.NET MVC 操作，它验证连接字符串是否可以正常工作以使用 RabbitMQ 连接到服务器。我如何做到这一点是通过简单地创建一个队列，订阅它，然后立即向它发布一条消息。我希望该消息最多在几秒钟后显示在我的订阅者身上，但事实并非如此。订阅者仅在我第一次调用该操作时收到通知（在我使用其基于 Web 的管理器从 RabbitMQ 删除队列之后），但是一旦我发布任何已创建队列的后续消息，则无法调用订阅者。请看一下我的代码，如果您看到我没有看到的东西，请告诉我。提前致谢。
//This is just the action called on a POST request.
//Here is where the test is done.
[HttpPost]
public void DoConnectionVerificationAsync()
{
const string paramName = "queueSuccessful";
try
{
//This is my routing key
const string routingKey = "management.verify";
//Here I declare the key and the exchange and bind them.
var queue = Queue.DeclareDurable(routingKey);
var exchange = Exchange.DeclareDirect("Orchard");
queue.BindTo(exchange, routingKey);
//Here I just generate a random int to send in the test message to the queue
Random random = new Random();
int randomInt = random.Next();
//Instantiate the actual message with the random integer.
var message = new Message<VerifyMessage>(new VerifyMessage
{
Content = randomInt.ToString(CultureInfo.InvariantCulture)
});
message.Properties.AppId = "CRM";
//Because this is an asynchronous action, here I hint the beginning of the async operation.
AsyncManager.OutstandingOperations.Increment();
//Here I have my subscriber. The subscriber gets called only the first time, when the queue hasn't been created yet. That's a problem, it should be called every time I publish, which is in the following lines of code.
_bus.Subscribe<VerifyMessage>(queue, (response, messageReceivedInfo) => Task.Factory.StartNew(() =>
{
VerifyMessage receivedMessage = response.Body;
string content = receivedMessage.Content;
int integer = int.Parse(content);
//I expect the int received from the queue is the same as the one I sent
bool success = integer == randomInt;
AsyncManager.Parameters[paramName] = success;
AsyncManager.OutstandingOperations.Decrement();
}));
//And here I publish the message. This always works, I can see the message stored in the queue using the web based RabbitMQ Manager
//The problem is that the message gets stuck in the queue and never gets sent to the subscriber defined above
using (var publishChannel = _bus.OpenPublishChannel(x => x.WithPublisherConfirms()))
{
publishChannel.Publish(exchange, routingKey, message, t =>
t.OnSuccess(() =>
{
// If we successfully publish, then there's nothing we really need to do. So this function stays empty.
})
.OnFailure(() =>
{
AsyncManager.Parameters[paramName] = false; AsyncManager.OutstandingOperations.Decrement();
}));
}
}
catch (EasyNetQException)
{
AsyncManager.Parameters[paramName] = false;
AsyncManager.OutstandingOperations.Decrement();
}
}
//These functions down here don't really matter, but I'm including them just in case so that you can see it all.
public ActionResult DoConnectionVerificationCompleted(bool queueSuccessful)
{
return RedirectToAction("VerifyQueueConnectionResult", new { queueSuccessful });
}
public ActionResult VerifyQueueConnectionResult(bool queueSuccessful)
{
VerifyQueueConnectionResultModel model = new VerifyQueueConnectionResultModel();
model.Succeded = queueSuccessful;
return View(model);
}