EasyNetQ. Advanced API - Publish does not produce response on RabbitServer - c#

Looking at EasyNetQ as replacement for our current library for MQ communication.
For Testing im trying to simply publish a number of messages to an exchange, using a custom naming strategy.
My method for publishing is in t he small test method below>
public void PublishTest()
{
var advancedBus = RabbitHutch.CreateBus("host=localhost;virtualHost=Test;username=guest;password=guest;").Advanced;
var routingKey = "SimpleMessage";
// declare some objects
var queue = advancedBus.QueueDeclare("Q.TestQueue.SimpleMessage");
var exchange = advancedBus.ExchangeDeclare("E.TestExchange.SimpleMessage", ExchangeType.Direct);
var binding = advancedBus.Bind(exchange, queue, routingKey);
var message = new SimpleMessage() {Test = "HELLO"};
for (int i = 0; i < 100; i++)
{
advancedBus.Publish(exchange, routingKey, true, true, new Message<SimpleMessage>(message));
}
advancedBus.Dispose();
}
The problem is that even thou the Exchange and Queue is created, and bound proper, publishing does not produce anything.
No messages hit the queue.
The graph in the Rabbit MQ management interface does not even show any activity on the exchange.
Am i missing something here? The code is basically taken straight from the documentation.
If im using the simple bus and simply just publish, an exchange is created and i can see via the management interface, that messages are being published.
Since the simple bus uses the advanced API to publish i assume that it is a setup issue that i am missing.
I hope someone can bring some insight:-)
/Thomas

I finally tracked down what was causing the problem.
It turns out that setting the parameter: immediate to true will cause the systems to throw exceptions.
the paramters is apparently not supported any more in the RabbitMQ client, see the discussion here: https://github.com/mikehadlow/EasyNetQ/issues/112
So the code below works just fine, mark the change from true to false in the publish method:
public void PublishTest()
{
var advancedBus = RabbitHutch.CreateBus("host=localhost;virtualHost=Test;username=guest;password=guest;").Advanced;
var routingKey = "SimpleMessage";
// declare some objects
var queue = advancedBus.QueueDeclare("Q.TestQueue.SimpleMessage");
var exchange = advancedBus.ExchangeDeclare("E.TestExchange.SimpleMessage", ExchangeType.Direct);
var binding = advancedBus.Bind(exchange, queue, routingKey);
var message = new SimpleMessage() {Test = "HELLO"};
for (int i = 0; i < 100; i++)
{
advancedBus.Publish(exchange, routingKey, true, false, new Message<SimpleMessage>(message));
}
advancedBus.Dispose();
}

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So, first of all, do not use EndpointConvention.Map<ManyToOneTransferMessage>(new Uri("queue:" + router.Name));. It isn't useful, and only adds to the confusion.
You can resolve the endpoint from the bus, but you have to realize that creating a bus for each call is a bad idea. It is best to start the bus at startup (you aren't even starting it in the code above), and stop it at application shutdown.
Then, for each call, you can use that bus to resolve the send endpoint and send the message.
var endpoint = await bus.GetSendEndpoint(new Uri("queue:" + router.Name));
await endpoint.Send(message);
Also, you should remove this since it will cause all messages to be moved to the _skipped queue:
cfg.ReceiveEndpoint(router.Name, e =>
{
e.RequiresSession = true;
e.MaxConcurrentCalls = 500;
});
You'll likely need to configure the queues separately, in advance, if you requireSession, although I don't see you setting a SessionId on the message so it likely will not work anyway without one.

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In the AWS console, you can see what instances are online, what are shutting down, and what are shut down. I'm trying to replicate this functionality in my application, but EC2 api doesn't seem to cooperate.
Here's what I'm doing:
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var status = ec2.DescribeInstanceStatus(rr);
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This works fine when the instance is online, but as soon as I request to shut it down, the instance disappears from the info.
How do I get info for all instances, including those shutting down, shut down and terminated ones?
By default, DescribeInstanceStatus only captures instances that are running. You can set the property IncludeAllInstances in the request to true to change this. From the documentation:
IncludeAllInstances
When true, includes the health status for all instances. When false,
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IncludeAllInstances = true
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Reference:
AWS Documentation - DescribeInstanceStatusRequest

Azure Service Bus SubscriptionClient.OnMessage always completes message when it shouldnt

I am trying to receive all messages for a given subscription to a Service Bus Topic, but for the context of this app I do not want them dead lettered at this time, I just want to view them and leave them on the subscription. Despite instantiating the Client as
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full method code below:
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Am I missing something ? Or is there an issue with auto dead-lettering with the onMessage() method?
Thanks !
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If you are trying to configure a multicast mechanism in which multiple listeners all receive the same message, then understand that all listeners on a given subscription will be competing for the same message. In order for every listener to receive its own copy of the message, then simply create a unique subscription to the topic for each listener.
If your intent is to delay re-delivery of the abandoned message, you might look at the SO question: What's the proper way to abandon an Azure SB Message so that it becomes visible again in the future in a way I can control?

using EasyNetQ multiple Handler for one consumer does not work

We are using RabbitMQ for queuing messages in C# .Net (EasyNetQ Client).
i want one consumer app (C# Console App) listen to one queue and provide multiple handlers for each message type.
I implemented this scenario and my code is here :
using (var advancedBus = RabbitHutch.CreateBus("host=localhost;prefetchcount=100")
.Advanced)
{
var queue = advancedBus.QueueDeclare("MyQueue");
advancedBus.Consume(queue, x => x
.Add<MessageType1>((message, info) =>
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Console.WriteLine("MessageType1 Body : " + message.Body.Body);
})
.Add<MessageType2>((message, info) =>
{
Console.WriteLine(" MessageType2 Body: " + message.Body.Body);
}).ThrowOnNoMatchingHandler = false);
}
My Problem :
But when i execute this consumer it does nothing. do not any thing happen.
i publish messages to that queue like this :
using (var advancedBus = RabbitHutch.CreateBus("host=localhost").Advanced)
{
var queue = advancedBus.QueueDeclare("MyQueue");
if (advancedBus.IsConnected)
advancedBus.Publish(Exchange.GetDefault(), queue.Name, false, false,
new Message<MessageType1>(change));
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}
What is the problem.
Ok, after testing this code, these are the problems:
First of all, you're disposing your advancedBus right after you register for consumption. You need to remember that when you invoke IAdvanceBus.Consume, you're only registering a callback for each message. If you dispose the bus immediately after registration, your delegate can't be invoked since the connection was already closed. So, you'll to remove the using statement around the rabbit declaration (don't forget to dispose it when you're done):
var advancedBus = RabbitHutch.CreateBus("host=localhost;prefetchcount=100").Advanced
Second, the immediate flag has been deprecated and shouldn't be used, the message doesn't seem to be getting to the queue. Change Publish to:
advancedBus.Publish(Exchange.GetDefault(), queue.Name, true, false,
new Message<MessageType1>(change));
Also, if you're running this from a console application, don't forget to use Console.ReadKey so your main thread doesn't terminate.
Here's a working code sample:
static void Main()
{
var change = new MessageType1();
var advancedBus = RabbitHutch.CreateBus("host=localhost").Advanced;
ConsumeMessage(advancedBus);
var queue = advancedBus.QueueDeclare("MyQueue");
if (advancedBus.IsConnected)
{
advancedBus.Publish(Exchange.GetDefault(), queue.Name, true, false,
new Message<MessageType1>(change));
}
else
{
Console.WriteLine("Can't connect");
}
Console.ReadKey();
}
private static void ConsumeMessage(IAdvancedBus advancedBus)
{
var queue = advancedBus.QueueDeclare("MyQueue");
advancedBus.Consume(queue, registration =>
{
registration.Add<MessageType1>((message, info) =>
{
Console.WriteLine("Body: {0}", message.Body);
});
});
}

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public static QueueClient GetServiceBusQueueClient(string queuename)
{
string connectionString;
if (RoleEnvironment.IsAvailable)
connectionString = CloudConfigurationManager.GetSetting("Microsoft.ServiceBus.ConnectionString");
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var namespaceManager = NamespaceManager.CreateFromConnectionString(connectionString);
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queue.EnableBatchedOperations = false;
queue.MaxDeliveryCount = 1000;
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queue = namespaceManager.GetQueue(queuename);
queue.EnableBatchedOperations = false;
queue.MaxDeliveryCount = 1000;
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mfs.NetMessagingTransportSettings.BatchFlushInterval = TimeSpan.Zero;
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string accessKey;
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if (RoleEnvironment.IsAvailable)
accessKey = RoleEnvironment.GetConfigurationSettingValue("AZURE_SERVICEBUS_ACCESS_KEY");
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MessagingFactory messagingFactory = MessagingFactory.Create(namespaceManager.Address, mfs);
QueueClient Client = messagingFactory.CreateQueueClient(queue.Path);
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But the EnableBatchedOperations is always true and the MaxDeliveryCount is always 10 by default.
Let me know if you know what's the issue
Thanks
If you want to set the EnabledBatchedOperations, you have to do that before you create the queue. you do that by creating a QueueDescription object then pass that to the CreateQueue method. For example:
QueueDescription orderQueueDescription =
new QueueDescription(queuename)
{
RequiresDuplicateDetection = true,
MaxDeliveryCount = 1000,
};
namespaceMgr.CreateQueue(orderQueueDescription);
Update:
The documentation is pretty clear on this:
Since metadata cannot be changed once a messaging entity is created, modifying the duplicate detection behavior requires deleting and recreating the queue. The same principle applies to any other metadata. [1]
QueueDescription Represents the metadata description of the queue.
[1] http://msdn.microsoft.com/en-us/library/windowsazure/hh532012.aspx
Update Azure SDK 2.3
UpdateQueue method on the NamespaceManager still doesn't let you update any properties apart from suspending or resuming the queue.
If you need to change MaxDeliveryCount on an existing queue and you don't want to delete and recreate the queue, your only option is to change it in the Azure portal.

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