asp.net – Sending Emails with Attachments Using RabbitMQ and AWS S3

I’m developing an application that utilizes RabbitMQ for message processing and AWS S3 for file storage.
My scenario involves sending emails that may include attachments of various file types, including PDFs, images, and documents. After uploading the PDFs to S3, I want to ensure efficient email delivery while allowing users to view the files within the email.
Is it best practice to download the PDF files from S3 directly within the RabbitMQ consumer when processing messages?

private async Task ProcessMessageAsync(string message)
{
    try
    {
        using (var scope = _serviceProvider.CreateScope())
        {
            var emailService = scope.ServiceProvider.GetRequiredService();
            var recipientService = scope.ServiceProvider.GetRequiredService();
            var typeService = scope.ServiceProvider.GetRequiredService();
            var s3Service = scope.ServiceProvider.GetRequiredService(); 

            var messageData = JsonConvert.DeserializeObject(message);
            var allRecipients = await recipientService.GetAllAsync();
            var notificationType = await typeService.GetTypeByIdAsync(messageData.TypeId);

            await Task.Delay(TimeSpan.FromSeconds(5));

            foreach (var recipientDto in messageData.RecipientId)
            {
                var recipientEmail = allRecipients.FirstOrDefault(r => r.id == recipientDto.id)?.Email;

                if (!string.IsNullOrEmpty(recipientEmail))
                {
                    var subject = "subject"; 
                    var emailBody = messageData.EditorContent;
                    var attachments = new List();

                    if (messageData.HasAttachment && messageData.AttachmentUrls != null)
                    {
                        foreach (var attachmentUrl in messageData.AttachmentUrls)
                        {
                            var attachmentBytes = await s3Service.DownloadFileFromS3Async(attachmentUrl);
                            var attachment = new Attachment(new MemoryStream(attachmentBytes), Path.GetFileName(attachmentUrl));
                            attachments.Add(attachment);
                        }

                        await emailService.SendEmailWithAttachmentAsync(recipientEmail, subject, emailBody, attachments);
                    }
                    else
                    {
                        await emailService.SendEmailAsync(recipientEmail, subject, emailBody);
                    }
                }
            }

            return true;
        }
    }
    catch (Exception ex)
    {
        Console.WriteLine($"Error processing message: {ex.Message}");
        return false;
    }
}

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