/// <summary>
/// Demostrate how to manually Create <see cref="ServiceBusProcessor"/>.
/// </summary>
/// <param name="cancellationToken"></param>
/// <returns></returns>
public async Task ProcessAsync(CancellationToken cancellationToken)
{
// 1. named value of the connection
var client = _connections.CreateClient(ServiceBusNames.QueuesOnly);
var options = new ServiceBusProcessorOptions
{
AutoCompleteMessages = false,
MaxConcurrentCalls = 1
};
// 2. Topic or Queue Name
var processor = client.CreateProcessor("sendgridwebhook_dev", options);
processor.ProcessMessageAsync += MessageHandler;
processor.ProcessErrorAsync += ErrorHandler;
async Task MessageHandler(ProcessMessageEventArgs args)
{
var body = args.Message.Body.ToString();
_logger.LogInformation(body);
// we can evaluate application logic and use that to determine how to settle the message.
await args.CompleteMessageAsync(args.Message);
}
Task ErrorHandler(ProcessErrorEventArgs args)
{
// the error source tells me at what point in the processing an error occurred
_logger.LogInformation(args.ErrorSource.ToString());
// the fully qualified namespace is available
_logger.LogInformation(args.FullyQualifiedNamespace);
// as well as the entity path
_logger.LogInformation(args.EntityPath);
_logger.LogInformation(args.Exception.ToString());
return(Task.CompletedTask);
}
// start processing
await processor.StartProcessingAsync();
}
public async Task PublishAsync(
string queueName,
QueueEvent @event,
CancellationToken cancellationToken = default)
{
var eventName = @event.GetType().Name.Replace(_QUEUEEVENTSUFFIX, string.Empty);
var jsonMessage = JsonConvert.SerializeObject(@event);
var body = Encoding.UTF8.GetBytes(jsonMessage);
var message = new Message
{
MessageId = Guid.NewGuid().ToString(),
Body = body,
Label = eventName,
};
var client = _connection.CreateClient(queueName);
cancellationToken.ThrowIfCancellationRequested();
await client.SendAsync(message);
}
public async Task SendMessagesAsync <T>(
IList <T> messages,
string subject = "",
CancellationToken cancellationToken = default)
{
var messageTypes = messages.Select(m => m?.GetType()).Distinct();
EnsureMessagesAreMapped(messageTypes);
var queuedMessages = new Queue <ServiceBusMessage>();
var producerInfo = _mappings[Named].Find(x => x.MessageType == typeof(T));
foreach (var message in messages)
{
var queuedMessage = new JsonSerializedMessage <T>(message);
if (!string.IsNullOrEmpty(producerInfo?.Subscription))
{
queuedMessage.Subject = producerInfo.Subscription;
}
if (!string.IsNullOrEmpty(subject))
{
queuedMessage.Subject = subject;
}
queuedMessages.Enqueue(queuedMessage);
}
var client = _connection.CreateClient(Named);
var sender = client.CreateSender(producerInfo.QueueOrTopicName);
// create a message batch that we can send
// total number of messages to be sent to the Service Bus queue
var messageCount = messages.Count;
// while all messages are not sent to the Service Bus queue
while (queuedMessages.Count > 0)
{
// start a new batch
using var messageBatch = await sender.CreateMessageBatchAsync(cancellationToken);
// add the first message to the batch
if (messageBatch.TryAddMessage(queuedMessages.Peek()))
{
// dequeue the message from the .NET queue once the message is added to the batch
queuedMessages.Dequeue();
}
else
{
// if the first message can't fit, then it is too large for the batch
throw new Exception($"Message {messageCount - messages.Count} is too large and cannot be sent.");
}
// add as many messages as possible to the current batch
while (queuedMessages.Count > 0 && messageBatch.TryAddMessage(queuedMessages.Peek()))
{
// dequeue the message from the .NET queue as it has been added to the batch
queuedMessages.Dequeue();
}
// now, send the batch
await sender.SendMessagesAsync(messageBatch, cancellationToken);
// if there are any remaining messages in the .NET queue, the while loop repeats
}
}
