Question

I am building an email app in ruby on rails and I had a basic version which just used to send emails using AWS SES but recently I received a mail from AWS team saying that most of the email which I have sent had bounced back and they will discontinue my account if I send emails to the bounced email ids.

Is there any way to verify before sending email to any address that whether that email exists or not and valid or not.

Any gem or work around will help me a lot

Answer 1

The general way to do this is purely from a system design point of view. If you are going to collect an email address from one of your users and send them email periodically, or as events happen etc, then you should first ask them to “verify their email address”. This typically involves generating a unique token, putting that into your database, linked with the user, then sending an email containing a URL with that unique token in it. The user clicks the link, which goes to a controller in your Rails application that matches the token against the user. If they can’t follow that link, they can’t read your emails, so don’t send further email to that address.

If you obtained the email addresses through “other means”, you’re down to setting a Return-Path address on the outgoing email (bounces will be sent here), then checking that mailbox for bounces. I’m also often suspicious of how people happen upon a list of email addresses that didn’t come from users consenting to an agreement with your website.

You could use the Mail gem to do this, but you need to know how to set up an SMTP server that pipes the email into your Rails application, which is not straightforward without prior experience. You can also use a variable Return-Path address (VERP), such as <some unique hash>[e-mail], where <some unique hash> references the email address in your system. This takes away the pain of trying to parse and interpret the bounce email, since the address it is sent to tells you who the bounced recipient is.