I have created a service bus queue in Azure and it works well. And if the message is not getting delivered within default try (10 times), it is correctly moving the message to the dead letter queue.
Now, I would like to resubmit this message from the dead letter queue back to the queue where it originated and see if it works again. I have tried the same using service bus explorer. But it gets moved to the dead letter queue immediately.
Is it possible to do the same, and if so how?
You'd need to send a new message with the same payload. ASB by design doesn't support message resubmission.
We had a batch of around 60k messages, which need to be reprocessed from the dead letter queue. Peeking and send the messages back via Service Bus Explorer took around 6 minutes per 1k messages from my machine. I solved the issue by setting a forward rule for DLQ messages to another queue and from there auto forward it to the original queue. This solution took around 30 seconds for all 60k messages.
Try to remove dead letter reason
resubmittableMessage.Properties.Remove("DeadLetterReason");
resubmittableMessage.Properties.Remove("DeadLetterErrorDescription");
full code
using Microsoft.ServiceBus.Messaging;
using System.Transactions;
namespace ResubmitDeadQueue
{
class Program
{
static void Main(string[] args)
{
var connectionString = "";
var queueName = "";
var queue = QueueClient.CreateFromConnectionString(connectionString, QueueClient.FormatDeadLetterPath(queueName), ReceiveMode.PeekLock);
BrokeredMessage originalMessage
;
var client = QueueClient.CreateFromConnectionString(connectionString, queueName);
do
{
originalMessage = queue.Receive();
if (originalMessage != null)
{
using (var scope = new TransactionScope(TransactionScopeAsyncFlowOption.Enabled))
{
// Create new message
var resubmittableMessage = originalMessage.Clone();
// Remove dead letter reason and description
resubmittableMessage.Properties.Remove("DeadLetterReason");
resubmittableMessage.Properties.Remove("DeadLetterErrorDescription");
// Resend cloned DLQ message and complete original DLQ message
client.Send(resubmittableMessage);
originalMessage.Complete();
// Complete transaction
scope.Complete();
}
}
} while (originalMessage != null);
}
}
}
Thanks to some other responses here!
We regularly need to resubmit messages. The answer from #Baglay-Vyacheslav helped a lot. I've pasted some updated C# code that works with the latest Azure.Messaging.ServiceBus Nuget Package.
Makes it much quicker/easier to process DLQ on both queues/topics/subscribers.
using Azure.Messaging.ServiceBus;
using System.Collections.Generic;
using System.Threading.Tasks;
using NLog;
namespace ServiceBus.Tools
{
class TransferDeadLetterMessages
{
// https://github.com/Azure/azure-sdk-for-net/blob/Azure.Messaging.ServiceBus_7.2.1/sdk/servicebus/Azure.Messaging.ServiceBus/README.md
private static Logger logger = LogManager.GetCurrentClassLogger();
private static ServiceBusClient client;
private static ServiceBusSender sender;
public static async Task ProcessTopicAsync(string connectionString, string topicName, string subscriberName, int fetchCount = 10)
{
try
{
client = new ServiceBusClient(connectionString);
sender = client.CreateSender(topicName);
ServiceBusReceiver dlqReceiver = client.CreateReceiver(topicName, subscriberName, new ServiceBusReceiverOptions
{
SubQueue = SubQueue.DeadLetter,
ReceiveMode = ServiceBusReceiveMode.PeekLock
});
await ProcessDeadLetterMessagesAsync($"topic: {topicName} -> subscriber: {subscriberName}", fetchCount, sender, dlqReceiver);
}
catch (Azure.Messaging.ServiceBus.ServiceBusException ex)
{
if (ex.Reason == Azure.Messaging.ServiceBus.ServiceBusFailureReason.MessagingEntityNotFound)
{
logger.Error(ex, $"Topic:Subscriber '{topicName}:{subscriberName}' not found. Check that the name provided is correct.");
}
else
{
throw;
}
}
finally
{
await sender.CloseAsync();
await client.DisposeAsync();
}
}
public static async Task ProcessQueueAsync(string connectionString, string queueName, int fetchCount = 10)
{
try
{
client = new ServiceBusClient(connectionString);
sender = client.CreateSender(queueName);
ServiceBusReceiver dlqReceiver = client.CreateReceiver(queueName, new ServiceBusReceiverOptions
{
SubQueue = SubQueue.DeadLetter,
ReceiveMode = ServiceBusReceiveMode.PeekLock
});
await ProcessDeadLetterMessagesAsync($"queue: {queueName}", fetchCount, sender, dlqReceiver);
}
catch (Azure.Messaging.ServiceBus.ServiceBusException ex)
{
if (ex.Reason == Azure.Messaging.ServiceBus.ServiceBusFailureReason.MessagingEntityNotFound)
{
logger.Error(ex, $"Queue '{queueName}' not found. Check that the name provided is correct.");
}
else
{
throw;
}
}
finally
{
await sender.CloseAsync();
await client.DisposeAsync();
}
}
private static async Task ProcessDeadLetterMessagesAsync(string source, int fetchCount, ServiceBusSender sender, ServiceBusReceiver dlqReceiver)
{
var wait = new System.TimeSpan(0, 0, 10);
logger.Info($"fetching messages ({wait.TotalSeconds} seconds retrieval timeout)");
logger.Info(source);
IReadOnlyList<ServiceBusReceivedMessage> dlqMessages = await dlqReceiver.ReceiveMessagesAsync(fetchCount, wait);
logger.Info($"dl-count: {dlqMessages.Count}");
int i = 1;
foreach (var dlqMessage in dlqMessages)
{
logger.Info($"start processing message {i}");
logger.Info($"dl-message-dead-letter-message-id: {dlqMessage.MessageId}");
logger.Info($"dl-message-dead-letter-reason: {dlqMessage.DeadLetterReason}");
logger.Info($"dl-message-dead-letter-error-description: {dlqMessage.DeadLetterErrorDescription}");
ServiceBusMessage resubmittableMessage = new ServiceBusMessage(dlqMessage);
await sender.SendMessageAsync(resubmittableMessage);
await dlqReceiver.CompleteMessageAsync(dlqMessage);
logger.Info($"finished processing message {i}");
logger.Info("--------------------------------------------------------------------------------------");
i++;
}
await dlqReceiver.CloseAsync();
logger.Info($"finished");
}
}
}
It may be "duplicate message detection" as Peter Berggreen indicated or more likely if you are directly moving the BrokeredMessage from the dead letter queue to the live queue then the DeliveryCount would still be at maximum and it would return to the dead letter queue.
Pull the BrokeredMessage off the dead letter queue, get the content using GetBody(), create in new BrokeredMessage with that data and send it to the queue. You can do this in a safe manor, by using peek to get the message content off the dead letter queue and then send the new message to the live queue before removing the message from the dead letter queue. That way you won't lose any crucial data if for some reason it fails to write to the live queue.
With a new BrokeredMessage you should not have an issue with "duplicate message detection" and the DeliveryCount will be reset to zero.
The Service Bus Explorer tool always creates a clone of the original message when you repair and resubmit a message from the deadletter queue. It could not be any different as by default Service Bus messaging does not provide any message repair and resubmit mechanism. I suggest you to investigate why your message gets ends up in the deadletter queue as well as its clone when you resubmit it. Hope this helps!
It sounds like it could be related to ASB's "duplicate message detection" functionality.
When you resubmit a message in ServiceBus Explorer it will clone the message and thereby the new message will have the same Id as the original message in the deadletter queue.
If you have enabled "Requires Duplicate Detection" on the queue/topic and you try to resubmit the message within the "Duplicate Detection History Time Window", then the message will immediately be moved to the deadletter queue again.
If you want to use Service Bus Explorer to resubmit deadletter messages, then I think that you will have to disable "Requires Duplicate Detection" on the queue/topic.
Related
with servicebus_client:
receiver = servicebus_client.get_subscription_receiver(topic_name=TOPIC_NAME, subscription_name=SUBSCRIPTION_NAME, max_wait_time=5)
with receiver:
for msg in receiver:
print("Received: " + str(msg))
receiver.complete_message(msg)
This code is taken from the Azure service bus code snippet in Microsoft portal. The code works fine till the it sends the messages, but when it reaches this part of the code, it is not getting in the for loop. The print statement is not getting execute. But I can see the Incoming and outcoming messages on the particular metrics page of that topic. Can I get some help here as I am new to Azure Service Bus?
Code for receive message from topic. its working as expected. you can try again with all library reference and follow all steps.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Azure.Messaging.ServiceBus;
namespace SubscriptionReceiver
{
internal class Program
{
// connection string to your Service Bus namespace
static string connectionString = "Endpoint=sb://xxx/;SharedAccessKeyName=RootManageSharedAccessKey;SharedAccessKey=xxx";
// name of the Service Bus topic
static string topicName = "mytopic";
// name of the subscription to the topic
static string subscriptionName = "S1";
// the client that owns the connection and can be used to create senders and receivers
static ServiceBusClient client;
// the processor that reads and processes messages from the subscription
static ServiceBusProcessor processor;
static async Task Main()
{
// The Service Bus client types are safe to cache and use as a singleton for the lifetime
// of the application, which is best practice when messages are being published or read
// regularly.
//
// Create the clients that we'll use for sending and processing messages.
client = new ServiceBusClient(connectionString);
// create a processor that we can use to process the messages
processor = client.CreateProcessor(topicName, subscriptionName, new ServiceBusProcessorOptions());
try
{
// add handler to process messages
processor.ProcessMessageAsync += MessageHandler;
// add handler to process any errors
processor.ProcessErrorAsync += ErrorHandler;
// start processing
await processor.StartProcessingAsync();
Console.WriteLine("Wait for a minute and then press any key to end the processing");
Console.ReadKey();
// stop processing
Console.WriteLine("\nStopping the receiver...");
await processor.StopProcessingAsync();
Console.WriteLine("Stopped receiving messages");
}
finally
{
// Calling DisposeAsync on client types is required to ensure that network
// resources and other unmanaged objects are properly cleaned up.
await processor.DisposeAsync();
await client.DisposeAsync();
}
}
// handle received messages
static async Task MessageHandler(ProcessMessageEventArgs args)
{
string body = args.Message.Body.ToString();
Console.WriteLine($"Received: {body} from subscription: {subscriptionName}");
// complete the message. messages is deleted from the subscription.
await args.CompleteMessageAsync(args.Message);
}
// handle any errors when receiving messages
static Task ErrorHandler(ProcessErrorEventArgs args)
{
Console.WriteLine(args.Exception.ToString());
return Task.CompletedTask;
}
}
}
Output :- Receive Message from Topic Subscription
It really annoys me that we're unable to move messages from a Dead Letter Queue over to the Original Queue for processing when using Azure Servicebus. So, I figured out that I will try to implement this feature myself. We are using Masstransit to publish events. The queuename in ASB will be an events full assembly name.
I've created an REST Endpoint in my application to move messages from the DLQ to the original queue for reprocessing. This is where I'm stuck at the moment.
To get all messages in a DLQ, the user gives me the queuename, and I will format it to contain the DeadLetterQueue. Like this:
myproject.events.usercreatedevent -> myproject.events.usercreatedevent/$DeadLetterQueue
I get all the messages from this queue by using classes from the Nuget package Microsoft.Azure.Servicebus
public async Task RequeueMessagesAsync(string queueName)
{
var msg = new MessageReceiver(BuildConnectionString(), queueName);
var messages = await msg.PeekAsync(50);
foreach (var message in messages)
{
var content = Encoding.UTF8.GetString(message.Body);
var jsonObject = JsonConvert.DeserializeObject<JObject>(content);
var destinationAddress = jsonObject["destinationAddress"].ToString();
var messageContent = jsonObject["message"].ToString();
var messageType = destinationAddress.Split("/").Last();
await _bus.SendAsync(jsonObject, messageType);
}
}
The when calling _bus.SendAsync(object, address) the message ends up in a _skipped queue. I think the reason for this is that the messageHeaders is set to JObject, and not the actual message type. I cannot use reflection to recreated the event either, as we have a lot of microservices and source code of the event it not necessarily available. The code behind the _bus.SendAsync(object, address) looks like this:
public async Task SendAsync(object message, string queueName, CancellationToken cancellationToken = default)
{
ISendEndpoint sender = await GetSenderAsync(queueName);
sender.ConnectSendObserver(new ErrorQueueConfiguration(_addressProvider.GetAddress("error")));
await sender.Send(message, cancellationToken);
}
Can I trick Masstransit to forward this "unknown" type to my Consumer by changing the MessageHeaders somehow? Have anyone successfully moved messages from a DLQ to its original queue?
How to read the message from the service bus dead-letter queue? I'm able to read message-id and a sequence number of the message, but I need the actual message. Can someone help me with this? Is it possible to read the actual message?
Before reading message form deadletter queue, you should check what was the reason of fail? If some service was not available then Create WebJob and try below code and process messages.
public void GetDeadLetterMessagesAsync(string connectionString, string queueName)
{
var queueClient = QueueClient.CreateFromConnectionString(connectionString, QueueClient.FormatDeadLetterPath(queueName));
while (true)
{
BrokeredMessage bmessgage = queueClient.Receive();
if (bmessgage != null)
{
string msg = new StreamReader(bmessgage.GetBody<Stream>(), Encoding.UTF8).ReadToEnd();
//Custom business logic to prcess your message
bmessgage.Complete();
}
else
{
break;
}
}
}
If message having an issue then you should read and display message on UI so back office team can correct message otherwise it will fail again.
I am creating a sample Azure Service Bus application. I created a namespace, topic and Subscription. I have written test messages to the topic and if I go to the subscription in the portal, I see that I have a new message every time I write a new one using the writer application.
But when I go to pull the message, nothing is retrieved. In troubleshooting, I changed the subscription name to an incorrect value and received an error. I changed it back and I get no output and none of the messages are removed when I look in Azure portal. I'm stuck... this seems easy, but it isn't working.
string connectionString = "Endpoint=sb://redacted for obvious reasons";
SubscriptionClient Client = SubscriptionClient.CreateFromConnectionString(connectionString, "NewOrders", "AllOrders");
// Configure the callback options.
OnMessageOptions options = new OnMessageOptions();
options.AutoComplete = false;
options.AutoRenewTimeout = TimeSpan.FromMinutes(1);
Client.OnMessage((message) =>
{
try
{
Console.WriteLine("Body: " + message.GetBody<string>());
message.Complete();
Console.ReadLine();
}
catch (Exception)
{
// Indicates a problem, unlock message in subscription.
message.Abandon();
}
}, options);
It seems that it is not the code issue. I create a demo to retrieve message from topic, it works correctly.
Before I try to retrieve message from topic, I send the message to the topic or make sure that there are messages for subscription. We could check that from the portal
Send message code demo.
private static void SendMessages()
{
topicClient = TopicClient.Create(TopicName);
List<BrokeredMessage> messageList = new List<BrokeredMessage>
{
CreateSampleMessage("1", "First message information"),
CreateSampleMessage("2", "Second message information"),
CreateSampleMessage("3", "Third message information")
};
Console.WriteLine("Sending messages to topic...");
foreach (BrokeredMessage message in messageList)
{
while (true)
{
try
{
topicClient.Send(message);
}
catch (MessagingException e)
{
if (!e.IsTransient)
{
Console.WriteLine(e.Message);
throw;
}
}
Console.WriteLine($"Message sent: Id = {message.MessageId}, Body = {message.GetBody<string>()}");
break;
}
}
topicClient.Close();
}
I also try your mentioned code, it also works correctly for me.
We also could get the demo project from the cloud Project from the template. We also could get more info about How to use Service Bus topics and subscriptions from the document.
I've written some code to delete test messages off a service bus topic. I'm the only one using this topic. It's using ReceiveAndDelete mode so I am assuming it's going to delete them, but every time I run the code it goes through this cycle of receiving messages, so I know it's not deleting them. What am I doing wrong?
public void TruncateTopic()
{
// reset topic for testing..
SubscriptionClient client = SubscriptionClient.CreateFromConnectionString(
connStr, QUEUENAME, "AllMessages",ReceiveMode.ReceiveAndDelete);
BrokeredMessage message = client.Peek();
while (message != null)
{
client.Receive();
message = client.Peek();
}
client.Close();
}
In your code you only do Peek on the Topic/Queue. Peek action never deletes the messages.
As you can clearly read from documentation Peek method only peeks into the subscription without actually receiving the message.
The ReceiveAndDelete receive mode will well work when you not just Peek the messages but Receive them instead! That is why it is named ReceiveAndDelete but not PeekAndDelete.
Change your code to:
BrokeredMessage message = client.Receive();
while (message != null)
{
message = client.Receive();
}
And everything will be fine.