Integrating E-Mail Functionality

[owensdj]

Any thoughts on the best way to add e-mail abilities to an application? It needs to be able to send individual messages, such as appointment reminders, as well as a few hundred newsletters at a time. I've never added this to an app so I didn't know if it was typically done all in the app or if the app connected to a 3rd-party e-mail service. Thanks.

 

[Markbnj]

Both, depending on the situation (i.e. volume, whether you need merge and templating, etc.), and also depending on what your web app is built in. For the simplest case you just need a class or module on the server side that connects to an smtp server.

 

[owensdj]

Markbnj, thanks for the reply. It's a Windows desktop application, not a web app. The app has a database of clients with an e-mail address for each one. The user should be able to send a newsletter to all clients, automatic appointment reminders, and individual mails. Hopefully they'll be able to do everything without leaving the main application.

 

[DaveSimmons]

One thing to keep in mind is message-per-hour limits for many mail services.

If you let your app send too many messages in a short time period the mail server may stop accepting mail.

For bulk email it might be better to use a mail service instead of a regular mailbox.

What is your development platform? (Win32, .NET, C++, VB, C#...?)

What will you be connecting to to send mail? The customer's own hosted web server, a mail hosting service lice Gmail, a mail sending service like SendGrid?

 

[owensdj]

The platform is a Win32 database application development tool called Clarion by SoftVelocity, but I could also put the e-mail functionality into a C++ DLL if I need to do that.

As far as what it will be connected to to send mail, that the main part I'm trying to decide. It won't be the customer's own hosted web server.

 

[DaveSimmons]

For outgoing mail, a specialized service like SendGrid or Amazon's Simple Email Service could work:

http://aws.amazon.com/ses/

I have not written code to use either service myself, but a co-worker used Amazon SES for sending error alerts for our Amazon cloud servers.

 

[owensdj]

DaveSimmons, Amazon's SES does look good, and it has good pricing at only $0.10/1000 emails. I'm also wondering if anybody has a service that lets the application send the list of e-mail recipients and the body of the message to the service and they send the message to all of the recipients for you?

 

[Train]

I use both Mailgun and Sendgrid. Both are good and cheap.

I know Sendgrid at least has list management that handles unsubscribes for you. I haven't used that aspect but it's there if you don't want to worry about list management.

 

[owensdj]

Train, ideally the service would let the custom desktop application handle the list management.

 

[mrjminer]

This is something that's not too difficult to do yourself if your project doesn't have the funds for a 3rd party service.

The difficult part is the appointments/reminders/sending at specific times. This may require some sort of scheduled script to run on a server (task schedule a batch file or something), or procedure that is run at intervals on the database.

However, if you are just manually pushing the e-mails / notifications out from a desktop application, you should be able to just do a "mail()" call through PHP, or a new "MailMessage" through a new "SmtpClient()" in .NET. I'm guessing .NET since you said it's a desktop app, in which case I would check out, IIRC, "System.Net" and "System.Net.Mail." Here's a basic example of something I did for a relative's website (ASP mvc):

[FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]private[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]bool[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] SendContactEmail([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]ContactFormModel[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] contactFormModel)
 {
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]bool[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] bSuccess = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]false[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2];
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]using[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] ([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]var[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] smtpClient = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]new[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]SmtpClient[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2]())
 {
 smtpClient.EnableSsl = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]false[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2];
 smtpClient.Host = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"mail.wherever.com"[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2];
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#008000][FONT=Consolas][SIZE=2][COLOR=#008000][FONT=Consolas][SIZE=2][COLOR=#008000]// ISPs/other things may block port 25; most have a secondary SMTP port (smarterasp, for instance, uses 8889)
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#008000][FONT=Consolas][SIZE=2][COLOR=#008000][FONT=Consolas][SIZE=2][COLOR=#008000]//smtpClient.Port = 25;
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2]smtpClient.Port = 8889;
 smtpClient.UseDefaultCredentials = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]false[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2];
 smtpClient.Credentials = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]new[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]NetworkCredential("smtpuser"[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2], [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"password"[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2]);
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]StringBuilder[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] sbMailBody = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]new[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]StringBuilder[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2]()
 .AppendLine([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"First Name: "[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] + contactFormModel.FirstName)
 .AppendLine([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"Last Name: "[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] + contactFormModel.LastName)
 .AppendLine([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"Email Address: "[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] + contactFormModel.EmailAddress)
 .AppendLine([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"Phone Number: "[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] + contactFormModel.PhoneNumber)
 .AppendLine([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"Message: "[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] + contactFormModel.ContactText);
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]try
[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2]{
 smtpClient.Send([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]new[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]MailMessage[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2](
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][EMAIL="sendfrom@wherever.com"]sendfrom@wherever.com[/EMAIL][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2],
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][EMAIL="sendto@whereever.com"]sendto@whereever.com[/EMAIL][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2],
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515][FONT=Consolas][SIZE=2][COLOR=#a31515]"Subject"[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2],
 sbMailBody.ToString()) { BodyEncoding = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]Encoding[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2].ASCII });
 bSuccess = [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]true[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2];
 }
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]catch[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] ([/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af][FONT=Consolas][SIZE=2][COLOR=#2b91af]Exception[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] ex)
 {
 }
 }
 [/SIZE][/FONT][/SIZE][/FONT][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff][FONT=Consolas][SIZE=2][COLOR=#0000ff]return[/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][/COLOR][/SIZE][/FONT][FONT=Consolas][SIZE=2][FONT=Consolas][SIZE=2] bSuccess;
 }
[/SIZE][/FONT][/SIZE][/FONT]

Most other things you mention would primarily be DB issues, but if you can use EF it should be pretty easy. For automatically sending, though, it would really depend on your app/requirements, and I haven't messed around with doing automatic sends too much.

 

[Train]

Train, ideally the service would let the custom desktop application handle the list management.

Do it however you want. Just look at the API's, not sure if you can dump an entire list on them with a body and have them send it, but I assume you can.

I insert the UserID into links in the body so I can track who has been active. So the one big API call won't work for me. I just HTTP POST to an API with recipient address and body and it goes pretty quick. I think I send to a list of about 8k emails in under 60 seconds. When I used to submit directly to an SMTP server, it took like 20 minutes, and failures/bounces were hard to track. With SendGrid I pull the bounces out in a CSV and can scrub my local list pretty easily.

 

[mrjminer]

Do it however you want. Just look at the API's, not sure if you can dump an entire list on them with a body and have them send it, but I assume you can.

I insert the UserID into links in the body so I can track who has been active. So the one big API call won't work for me. I just HTTP POST to an API with recipient address and body and it goes pretty quick. I think I send to a list of about 8k emails in under 60 seconds. When I used to submit directly to an SMTP server, it took like 20 minutes, and failures/bounces were hard to track. With SendGrid I pull the bounces out in a CSV and can scrub my local list pretty easily.

Just bouncing off this.. what I posted hasn't been used in any kind of large-scale environment / bulk sends. So an e-mail service it might be a better solution based on what Train said since they'll definitely have some ninjas to configure their servers / caching mechanisms specifically tailored for sending e-mails in bulk / included statistics. It will depend on what you need, though.