I'm creating a Windows Service in C#.
What is the best way to listen for messages?? How do I code this properly??
You don't listen. You configure MSMQ Activation to activate your component when messages arrive. The link has all the details you need, code and configuration.
As previously stated, MSMQ Activation is probably the best way, if you can use that. Alternatively, here is code that I've used:
var ts = new TimeSpan(0, 0, 10);
MessageQueue q = GetQueue<T>();
while (true)
{
try
{
Message msg = q.Receive(ts);
var t = (T)msg.Body;
HandleMessage(t);
}
catch (MessageQueueException e)
{
// Test to see if this was just a timeout.
// If it was, just continue, there were no msgs waiting
// If it wasn't, something horrible may have happened
}
}
Related
I am using Azure.Messaging.ServiceBus nuget package to work with Azure service bus. We have created a topic and a subscription. The subscription has 100+ messages. We want to read all the message and continue to read message as they arrive.
Microsoft.Azure.ServiceBus package (deprecated now) provided RegisterMessageHandler which use to process every incoming message. I am not able to find similar option under Azure.Messaging.ServiceBus nuget package.
I am able to read one message at a time but I have to call await receiver.ReceiveMessageAsync(); every time manually.
To receive multiple messages (a batch), you should use ServiceBusReceiver.ReceiveMessagesAsync() (not plural, not singular 'message'). This method will return whatever number of messages it can send back. To ensure you retrieve all 100+ messages, you'll need to loop until no messages are available.
If you'd like to use a processor, that's also available in the new SDK. See my answer to a similar question here.
As suggested by #gaurav Mantri, I used ServiceBusProcessor class to implement event based model for processing messages
public async Task ReceiveAll()
{
string connectionString = "Endpoint=sb://sb-test-today.servicebus.windows.net/;SharedAccessKeyName=manage;SharedAccessKey=8e+6SWp3skB3Aedsadsadasdwz5DU=;";
string topicName = "topicone";
string subscriptionName = "subone";
await using var client = new ServiceBusClient(connectionString, new ServiceBusClientOptions
{
TransportType = ServiceBusTransportType.AmqpWebSockets
});
var options = new ServiceBusProcessorOptions
{
// By default or when AutoCompleteMessages is set to true, the processor will complete the message after executing the message handler
// Set AutoCompleteMessages to false to [settle messages](https://learn.microsoft.com/en-us/azure/service-bus-messaging/message-transfers-locks-settlement#peeklock) on your own.
// In both cases, if the message handler throws an exception without settling the message, the processor will abandon the message.
AutoCompleteMessages = false,
// I can also allow for multi-threading
MaxConcurrentCalls = 1
};
await using ServiceBusProcessor processor = client.CreateProcessor(topicName, subscriptionName, options);
processor.ProcessMessageAsync += MessageHandler;
processor.ProcessErrorAsync += ErrorHandler;
await processor.StartProcessingAsync();
Console.ReadKey();
}
public async Task MessageHandler(ProcessMessageEventArgs args)
{
string body = args.Message.Body.ToString();
Console.WriteLine(body);
// we can evaluate application logic and use that to determine how to settle the message.
await args.CompleteMessageAsync(args.Message);
}
public Task ErrorHandler(ProcessErrorEventArgs args)
{
// the error source tells me at what point in the processing an error occurred
Console.WriteLine(args.ErrorSource);
// the fully qualified namespace is available
Console.WriteLine(args.FullyQualifiedNamespace);
// as well as the entity path
Console.WriteLine(args.EntityPath);
Console.WriteLine(args.Exception.ToString());
return Task.CompletedTask;
}
I use IBM XMS to connect to a third party to send and receive messages.
UPDATE:
Client .Net Core 3.1
IBM XMS library version from Nuget. Tried 9.2.4 and 9.1.5 with same results
Same code used to work fine a week ago - so something must have changed in the MQ manager or somewhere in my infrastructure
SSL and client certificates
I have been using a receive with timeout for a while without problems but since last week I started to not see any messages to pick - even when they were there - but once I changed to the not timeout receive method I started again to pick messages every 5 minutes.
Looking at the XMS logs I can see the messages are actually read almost immediately with and without timeout but that XMS seems to be deciding to wait for those 5 minutes before returning the message...
I haven't changed anything in my side and the third party reassures they haven't either.
My question is: given the below code used to receive is there anything there that may be the cause of the 5 minutes wait? Any ideas on things I can try? I can share the XMS logs too if that helps.
// This is used to set the default properties in the factory before calling the receive method
private void SetConnectionProperties(IConnectionFactory cf)
{
cf.SetStringProperty(XMSC.WMQ_HOST_NAME, _mqConfiguration.Host);
cf.SetIntProperty(XMSC.WMQ_PORT, _mqConfiguration.Port);
cf.SetStringProperty(XMSC.WMQ_CHANNEL, _mqConfiguration.Channel);
cf.SetStringProperty(XMSC.WMQ_QUEUE_MANAGER, _mqConfiguration.QueueManager);
cf.SetStringProperty(XMSC.WMQ_SSL_CLIENT_CERT_LABEL, _mqConfiguration.CertificateLabel);
cf.SetStringProperty(XMSC.WMQ_SSL_KEY_REPOSITORY, _mqConfiguration.KeyRepository);
cf.SetStringProperty(XMSC.WMQ_SSL_CIPHER_SPEC, _mqConfiguration.CipherSuite);
cf.SetIntProperty(XMSC.WMQ_CONNECTION_MODE, XMSC.WMQ_CM_CLIENT);
cf.SetIntProperty(XMSC.WMQ_CLIENT_RECONNECT_OPTIONS, XMSC.WMQ_CLIENT_RECONNECT);
cf.SetIntProperty(XMSC.WMQ_CLIENT_RECONNECT_TIMEOUT, XMSC.WMQ_CLIENT_RECONNECT_TIMEOUT_DEFAULT);
}
public IEnumerable<IMessage> ReceiveMessage()
{
using var connection = _connectionFactory.CreateConnection();
using var session = connection.CreateSession(false, AcknowledgeMode.AutoAcknowledge);
using var destination = session.CreateQueue(_mqConfiguration.ReceiveQueue);
using var consumer = session.CreateConsumer(destination);
connection.Start();
var result = new List<IMessage>();
var keepRunning = true;
while (keepRunning)
{
try
{
var sw = new Stopwatch();
sw.Start();
var message = _mqConfiguration.ConsumerTimeoutMs == 0 ? consumer.Receive()
: consumer.Receive(_mqConfiguration.ConsumerTimeoutMs);
if (message != null)
{
result.Add(message);
_messageLogger.LogInMessage(message);
var ellapsedMillis = sw.ElapsedMilliseconds;
if (_mqConfiguration.ConsumerTimeoutMs == 0)
{
keepRunning = false;
}
}
else
{
keepRunning = false;
}
}
catch (Exception e)
{
// We log the exception
keepRunning = false;
}
}
consumer.Close();
destination.Dispose();
session.Dispose();
connection.Close();
return result;
}
The symptoms look like a match for APAR IJ20591: Managed .NET SSL application making MQGET calls unexpectedly receives MQRC_CONNECTION_BROKEN when running in .NET Core. This impacts messages larger than 15kb and IBM MQ .net standard (core) libraries using TLS channels. See also this thread. This will be fixed in 9.2.0.5, no CDS release is listed.
It states:
Setting the heartbeat interval to lower values may reduce the frequency of occurrence.
If your .NET application is not using a CCDT you can lower the heartbeat by having the SVRCONN channel's HBINT lowered and reconnecting your application.
I have a legacy Windows service running on Server 2008 that reads messages from a Transactional MSMQ Queue. This is not configured as a WCF service.
We are wanting to improve the handling of failed and poison messages in code (C# 4.0) by catching custom exceptions and sending the related message to a separate 'failed' or 'poison' queue depending upon the type of exception thrown.
I can't get the Catch code to send the message to the separate queue - it disappears from the original queue (as desired!) but doesn't show up in the 'failed' queue.
For testing all of the queues have no Authentication required and permissions are set to allow Everyone to do everything.
Clearly something is missing or wrong and I suspect it is transaction related, but I can't see it. Or perhaps this is not possible the way I am trying to do it ?
Any guidance / suggestions appreciated!
Our simplified PeekCompleted Event code:
private void MessageReceived(object sender, PeekCompletedEventArgs e)
{
using (TransactionScope txnScope = new TransactionScope())
{
MyMessageType currentMessage = null;
MessageQueue q = ((MessageQueue)sender);
try
{
Message queueMessage = q.EndPeek(e.AsyncResult);
currentMessage = (FormMessage)queueMessage.Body;
Processor distributor = new Processor();
Processor.Process(currentMessage); // this will throw if need be
q.ReceiveById(e.Message.Id);
txnScope.Complete();
q.BeginPeek();
}
catch (MyCustomException ex)
{
string qname = ".\private$\failed";
if (!MessageQueue.Exists(qname)){
MessageQueue.Create(qname , true);
}
MessageQueue fq = new MessageQueue(qname){
Formatter = new BinaryMessageFormatter()
};
System.Messaging.Message message2 = new System.Messaging.Message{
Formatter = new BinaryMessageFormatter(),
Body = currentMessage,
Label = "My Failed Message";
};
fq.Send(message2); //send to failed queue
q.ReceiveById(e.Message.Id); //off of original queue
txnScope.Complete(); // complete the trx
_queue.BeginPeek(); // next or wait
}
//other catches handle any cases where we want to tnxScope.Dispose()
EDIT : October 8, 2013
Hugh's answer below got us on the right track. Inside the Catch block the Failed Queue was already created as transactional
MessageQueue.Create(qname , true);
but the Send needed a TransactionType parameter
fq.Send(message2,MessageQueueTransactionType.Single);
That did the trick. Thanks Hugh!
If the message is disappearing from your original queue then that means your code is reaching the second scope.Complete() (in your catch block).
This means the problem has to do with your send to the error queue.
I would suggest that you need to create the queue as transactional because you are sending from within a scope.
MessageQueue fq = new MessageQueue(qname, true){
Formatter = new BinaryMessageFormatter()
};
Then you need to do a transactional send:
fq.Send(message2, Transaction.Current);
See if this works.
I am relatively new both to MSMQ and Threading in .NET. I have to create a service which listen in different threads, via TCP and SNMP, several network Devices and all this stuff run in dedicated threads, but here also is required to listen on MSMQ Queue from another applications.
I am analyzing another similar projects and there is used next logic:
private void MSMQRetrievalProc()
{
try
{
Message mes;
WaitHandle[] handles = new WaitHandle[1] { exitEvent };
while (!exitEvent.WaitOne(0, false))
{
try
{
mes = MyQueue.Receive(new TimeSpan(0, 0, 1));
HandleMessage(mes);
}
catch (MessageQueueException)
{
}
}
}
catch (Exception Ex)
{
//Handle Ex
}
}
MSMQRetrievalThread = new Thread(MSMQRetrievalProc);
MSMQRetrievalThread.Start();
But in another service (message dispatcher) I used asynchronous messages' reading based on MSDN Example:
public RootClass() //constructor of Main Class
{
MyQ = CreateQ(#".\Private$\MyQ"); //Get or create MSMQ Queue
// Add an event handler for the ReceiveCompleted event.
MyQ.ReceiveCompleted += new
ReceiveCompletedEventHandler(MsgReceiveCompleted);
// Begin the asynchronous receive operation.
MyQ.BeginReceive();
}
private void MsgReceiveCompleted(Object source, ReceiveCompletedEventArgs asyncResult)
{
try
{
// Connect to the queue.
MessageQueue mq = (MessageQueue)source;
// End the asynchronous Receive operation.
Message m = mq.EndReceive(asyncResult.AsyncResult);
// Process received message
// Restart the asynchronous Receive operation.
mq.BeginReceive();
}
catch (MessageQueueException Ex)
{
// Handle sources of MessageQueueException.
}
return;
}
Does asynchronous handling suppose that every message will be handled in other than main thread?
Could and need this (2nd) approach be put in separate thread?
Please advice better approach or some simple alternatives.
Messages arrival in Queue doesn't have some rule-defined behavior. It may be that for long time no nay message will arrive or in one second there my arrive many (up to 10 or even more) messages. Based on actions defined in some message it will need to delete/change some objects having running threads.
I highly recommend using WCF for MSMQ.
http://msdn.microsoft.com/en-us/library/ms789048.aspx
This allows you to both asynchronous handle the incoming calls using the WCF threading model which allows for throttling, capping, retries, etc...
At this line of code i am getting the error as i mentioned
I declared MSMQ_NAME as string as follows
private const string MSMQ_NAME = ".\\private$\\ASPNETService";
private void DoSomeMSMQStuff()
{
using (MessageQueue queue = new MessageQueue(MSMQ_NAME))
{
queue.Send(DateTime.Now); //Exception raises
queue.Close();
}
}
Can you first verify the queue is existing with the name 'ASPNETService' at below location?
Computer Management -> Services and Applications -> Message Queuing -> Private Queues
I had a similar problem. I was confused because my code worked on my local development machine, but not in production. Even stranger, the queues were created the exact same way.
It turns out that IIS doesn't have access to them by default. I just opened up the permissions.
Computer Management -> Private Queues -> right-click queue name -> Properties -> Security Tab -> click "Everyone" user -> click Full Control/Allow checkbox -> click OK
This fixed it for me, and in my case it's not an issue, but you may want to think about the ramifications of just opening it up for all users.
Also, I had to do this across all queues on all servers. There doesn't seem to be a way to multi-select queues or folders in order to set permissions for multiple queues simultaneously.
I was having the same problem.
I had created a new private queue and gave Full Permission to Everyone.
But I was still catching a "Queue does not exist or you do not have sufficient permissions to perform the operation" when trying to Send() to the queue. And I was able to verify that MessageQueue.Exists(".\\private$\\myqueue") was returning true.
Restarting the Message Queuing Service resolved my the problem for me.
I had same problem and I did like below where I check whether queue exists or not. If yes send message else create queue and then send message
MessageQueue msgQueue = null;
string queuePath = ".\\Private$\\billpay";
Payment newPayment = new Payment()
{
Payee = txtPayee.Text,
Payor = txtPayor.Text,
Amount = Convert.ToInt32(txtAmount.Text),
DueDate = dpDueDate.SelectedDate.Value.ToShortDateString()
};
Message msg = new Message();
msg.Body = newPayment;
msg.Label = "Gopala - Learning Message Queue";
if (MessageQueue.Exists(queuePath) == false)
{
//Queue doesnot exist so create it
msgQueue = MessageQueue.Create(queuePath);
}
else
{
msgQueue = new MessageQueue(queuePath);
}
msgQueue.Send(msg);
I was facing the same problem, I had resolved it using the following class to create queue
private MessageQueue messageQueue;
public const string DEFAULT_QUEUE_NAME = "newQueue";
public const string QUEUENAME_PREFIX = ".\\Private$\\";
public static string QueueName
{
get
{
string result = string.Format("{0}{1}", QUEUENAME_PREFIX, DEFAULT_QUEUE_NAME);
return result;
}
}
public void SendMessage()
{
string queuePath = QueueName;
MessageQueue messageQueue = MessageQueue.Create(queuePath);
messageQueue.Send("msg");
}
Create message queue in same manner for receiving the message.
For others struggling with this and pulling their hair out like I have been, I finally found something that works when all of the upvoted suggestions failed.
Even if you think the host name of your target queue's hosting system is being resolved correctly, don't believe it. Try replacing the host name with an IP address and see if it works. It does for me. I can WRITE to a public queue using a host name on my remote server without problems, but trying to READ from it produces exactly the error listed for this question.
For example, if I declare the following:
private static string QueueName = #"FormatName:DIRECT=TCP:SOMEHOST\MyQueue";
private static System.Messaging.MessageQueue Queue = new System.Messaging.MessageQueue(QueueName);
Where "MyQueue" is a public queue on server SOMEHOST, the following code will successfully insert messages to the queue, but always fails on the Receive():
Queue.Formatter = new XmlMessageFormatter(new Type[] { typeof(String) });
// The Receive() call here is a blocking call. We'll wait if there is no message in the queue, and processing
// is halted until there IS a message in the queue.
//
try
{
Queue.Send("hello world", System.Messaging.MessageQueueTransactionType.Single);
var msg = Queue.Receive(MessageQueueTransactionType.Single);
}
catch (Exception ex)
{
// todo error handling
}
One simple change in how I specify the queue location is all that's needed to make the Receive() stop failing with the dreaded "queue does not exist or you do not have sufficient permissions" error:
private static string QueueName = #"FormatName:DIRECT=TCP:192.168.1.100\MyQueue";
(Obviously I've obfuscated IP addresses and other sensitive info). Using the IP address is not obviously a production-worthy scenario, but it did point me to some type of name resolution problem as being the possible cause of the error. I cannot explain why Send() works but Receive() does not when I am using a host name instead of IP, but I can reproduce these results consistently. Until I can figure out what's going on with the name resolution, I'm no longer wasting a day trying to read messages from a queue.