public async Task <ActionResult> SendNewsletter(HttpPostedFileBase recipient, string subject, string mailMessage, HttpPostedFileBase[] fileAttachments = null)
{
try
{
// begin validations
if (recipient == null)
{
throw new Exception("Recipient file must be uploaded");
}
if (string.IsNullOrWhiteSpace(subject))
{
throw new Exception("Subject is required");
}
if (string.IsNullOrWhiteSpace(mailMessage))
{
throw new Exception("Mail body is required");
}
DataTable recipients = LoadExcelFile("recipient", "Recipients");
if (recipients.Rows.Count == 0)
{
throw new Exception("At least one recipient is required.");
}
if (!recipients.Columns.Contains("Email"))
{
throw new Exception("Column Email is required in the recipients file uploaded.");
}
if (!recipients.Columns.Contains("Title"))
{
throw new Exception("Column Title is required in the recipients file uploaded.");
}
if (!recipients.Columns.Contains("Name"))
{
throw new Exception("Column Name is required in the recipients file uploaded.");
}
// end validations
SendNewsletterCallResult result = new SendNewsletterCallResult();
await DispatchEmailsAsync(result, recipients, subject, mailMessage, fileAttachments);
if (result.NoOfFailedMessages > 0)
{
ViewBag.Message = string.Format($"{recipients.Rows.Count - result.NoOfFailedMessages} of {recipients.Rows.Count} email was sent. {result.NoOfFailedMessages} failed to deliver.");
}
else
{
ViewBag.Message = "Mail was sent to all recipients.";
}
return(View());
}
catch (Exception ex)
{
ViewBag.Message = "Error: " + ex.Message;
return(View());
}
}
private async Task <bool> DispatchEmailsAsync(SendNewsletterCallResult result, DataTable recipients, string subject, string mailMessage, HttpPostedFileBase[] fileAttachments = null)
{
int noOfEmailsProcessed = 0, noOfEmailsPerHour = int.Parse(ConfigurationManager.AppSettings["NoOfEmailsPerHour"].ToString());
DateTime dt = DateTime.Now;
int noOfFailedMessages = 0;
DataAccess dataAccess = new DataAccess(DataProvider.MsSQLServer, ConfigurationManager.ConnectionStrings["AlertDataConnectionString"].ConnectionString);
string reference = Guid.NewGuid().ToString();
foreach (DataRow recipient in recipients.Rows)
{
string email = recipient["Email"].ToString().Trim();
if (IEIA.CommonUtil.RegexUtilities.IsValidEmail(email))
{
string mailBody = string.Format($"Dear {recipient["Title"].ToString().Trim()} {recipient["Name"].ToString().Trim()},<br><br>{mailMessage}");
var isMailSent = await SendEmailAsync(subject, mailBody, email, fileAttachments);
if (!isMailSent)
{
noOfFailedMessages++;
}
dataAccess.Execute("INSERT INTO MessageHistory (MessageType, Recipient, Message, Subject, IsSent, IsDelivered, Ref, ProviderID, UserName) VALUES ('E', @Recipient, @Message, @Subject, @IsSent, 0, @Ref, @ProviderID, @UserName)",
new DataParam[] {
new DataParam("@Recipient", email),
new DataParam("@Message", mailBody),
new DataParam("@Subject", subject),
new DataParam("@IsSent", isMailSent),
new DataParam("@Ref", reference),
new DataParam("@ProviderID", 3),
new DataParam("@UserName", Session["userName"])
});
noOfEmailsProcessed++;
}
TimeSpan span = DateTime.Now.Subtract(dt);
if (span.Minutes <= 60 && noOfEmailsProcessed >= noOfEmailsPerHour)
{
System.Threading.Thread.Sleep(60 - span.Minutes); // wait for the remaining time to 1 hour
// reset the time and no of e-mails sent
dt = DateTime.Now;
noOfEmailsProcessed = 0;
}
}
dataAccess = null;
result.NoOfFailedMessages = noOfFailedMessages;
return(true);
}
