private async Task processAsync(EmailMessage emailMessage)
{
logger.LogDebug($"Start processing email message {emailMessage.Id}");
Interlocked.Increment(ref consumerTasksPending);
try {
await processor.ProcessAsync(emailMessage);
logger.LogDebug($"Successfully processed email message {emailMessage.Id}");
} catch (SingleProcessingException e) {
logger.LogError(e, $"Delivery error for message {emailMessage.Id}");
throw e;
} catch (GeneralProcessingException e) {
logger.LogError(e, $"General delivery problem for message {emailMessage.Id}");
await messageSource.RetryAsync(emailMessage);
} catch (Exception e) {
logger.LogError(e, $"Unexpected Exception while processing message {emailMessage.Id}");
throw e;
} finally {
Interlocked.Decrement(ref consumerTasksPending);
}
}