private void ConsumeMessage(SubscriberInfo subscriberInfo, IBrokeredMessage brokeredMessage)
{
try
{
var messageBody = brokeredMessage.GetBody <string>();
var message = JsonConvert.DeserializeObject <TMessage>(messageBody);
_logService.Debug("Consuming message id '{0}', topic/subscription '{1}', body '{2}'",
brokeredMessage.MessageId, subscriberInfo.SubscriptionPath, messageBody);
var state = subscriberInfo.Subscriber.Consume(message);
HandleMessageResult(subscriberInfo, state, brokeredMessage, messageBody);
_logService.Debug("Consumed message id '{0}', topic/subscription '{1}', body '{2}'",
brokeredMessage.MessageId, subscriberInfo.SubscriptionPath, messageBody);
}
catch (Exception e)
{
var deadLetterReason = string.Format(
"Unexpected exception consuming message id '{0}, topic/subscription '{1}': message will be dead-lettered",
brokeredMessage.MessageId, subscriberInfo.SubscriptionPath);
_logService.Error(deadLetterReason, e);
brokeredMessage.DeadLetter();
}
}
private void HandleMessageResult(SubscriberInfo subscriberInfo, ServiceBusMessageStates state, IBrokeredMessage brokeredMessage, string messageBody)
{
_logService.Debug("Handling message id '{0}', topic/subscription '{1}', state '{2}', body '{3}' ",
brokeredMessage.MessageId, subscriberInfo.SubscriptionPath, state, messageBody);
switch (state)
{
case ServiceBusMessageStates.Complete:
brokeredMessage.Complete();
break;
case ServiceBusMessageStates.Abandon:
brokeredMessage.Abandon();
break;
case ServiceBusMessageStates.DeadLetter:
brokeredMessage.DeadLetter();
break;
case ServiceBusMessageStates.Requeue:
var scheduledEnqueueTimeUtc = brokeredMessage.ScheduledEnqueueTimeUtc == DateTime.MinValue ? DateTime.UtcNow.AddSeconds(30) : GetDefaultRequeueDateTimeUtc();
var newBrokeredMessage = new BrokeredMessage(messageBody)
{
ScheduledEnqueueTimeUtc = scheduledEnqueueTimeUtc
};
subscriberInfo.TopicClient.Send(newBrokeredMessage);
brokeredMessage.Complete();
break;
default:
var deadLetterReason = string.Format(
"Invalid message state '{0}' for message id '{1}', topic/subscription '{2}': message will be dead-lettered",
state, brokeredMessage.MessageId, subscriberInfo.SubscriptionPath);
_logService.Error(deadLetterReason);
brokeredMessage.DeadLetter();
break;
}
_logService.Debug("Handled message id '{0}', topic/subscription '{1}', state '{2}', body '{3}' ",
brokeredMessage.MessageId, subscriberInfo.SubscriptionPath, state, messageBody);
}
static bool SafeDeadLetter(IBrokeredMessage msg, string reason)
{
try {
// Mark brokered message as complete.
msg.DeadLetter(reason, "Max retries Exceeded.");
// Return a result indicating that the message has been completed successfully.
return(true);
}
catch (MessageLockLostException) {
// It's too late to compensate the loss of a message lock. We should just ignore it so that it does not break the receive loop.
// We should be prepared to receive the same message again.
}
catch (MessagingException) {
// There is nothing we can do as the connection may have been lost, or the underlying topic/subscription may have been removed.
// If Complete() fails with this exception, the only recourse is to prepare to receive another message (possibly the same one).
}
return(false);
}
static bool SafeDeadLetter(IBrokeredMessage msg, string reason) {
try {
// Mark brokered message as complete.
msg.DeadLetter(reason, "Max retries Exceeded.");
// Return a result indicating that the message has been completed successfully.
return true;
}
catch (MessageLockLostException) {
// It's too late to compensate the loss of a message lock. We should just ignore it so that it does not break the receive loop.
// We should be prepared to receive the same message again.
}
catch (MessagingException) {
// There is nothing we can do as the connection may have been lost, or the underlying topic/subscription may have been removed.
// If Complete() fails with this exception, the only recourse is to prepare to receive another message (possibly the same one).
}
return false;
}