When creating your template, you can set the verify_post_url field. If the message is used as double opt-in and the verification is successful, the send_id and email address will be posted to this url.

Now you need to write the script that processes the postback at that URL. The script can expect to receive the following POST parameters:

• email: the email address that has been verified
• send_id: the send_id of the verification email

Example values returned:

Post Data:
Array
(
[email] => example@sailthru.com
[send_id] => WFmfCby1nMkoi0ZI
[action] => verify
[api_key] => 2479370a3ed840cf184df1f5f00f32f1
[sig] => 3d5b94ae50d6e65fbc94cc93326feffb
)

For those Sailthru libraries that contain the receiveVerifyPost(), this function returns true if the incoming POST data matches that of an email-verification postback. For extra security, it actually makes an API call to make sure the incoming data makes sense.

Example (PHP)

$sailthruClient = new Sailthru_Client($api_key, $api_secret);
  if ($sailthruClient->receiveVerifyPost()) {

      // we've received a verification postback
      $st = $db->prepare('UPDATE user SET is_verified = 1 WHERE email = :email');
      if (!$st->execute(<a href="http://www.php.net/array">array</a>(':email' => $_POST['email']))) {

          <a href="http://www.php.net/header" rel="nofollow">header</a>('HTTPS/1.1 500 Internal Server Error');
          // or whatever other user verification you want to do!
      }
  } else {
      <a href="http://www.php.net/header" rel="nofollow">header</a>('HTTPS/1.1 403 Forbidden');
  }

This can be useful if you need to track opt-outs on your own, perhaps because you are using other mailing systems in conjunction with Sailthru, or you want to set an opt-out flag internally on your database.

You can set an Opt-out Postback URL via your API & Postbacks Settings page. This will apply to all opt-outs from Sailthru-powered emails.

Every time a user clicks an opt-out link, or clicks a button on a confirmed opt-out page, Sailthru will post to your page.

Opt-Out Types and Parameters

There are four types of opt-outs:

• • all – User wants to be removed from all emails from your site, or clicked the ‘Spam’ button in their email application

• basic – User wants to be removed from all emails (campaigns and transactionals) except for the transactional emails that are set as “basic.” The basic status is set by your Sailthru Customer Success representative on individual templates that you use for transactionals. The accepted communication types include password reset, purchase receipt, shipping confirmation, etc.

When an opt-out occurs, Sailthru will post the following parameters, with the mode parameter representing one of the above opt-out types. The POST call made to their endpoint is URL encoded, the actual data payload of a postback is array data.

Note: The parameters blast_id and list are only provided when the opt-out action was initiated from a Campaign send.

All Opt-outs: User wants to be removed from all emails from your site

Example Optout Postback Data

Post Data:
Array
(
 [email] => example@sailthru.com
 [mode] => basic
 [optout] => 1
 [action] => optout
 [api_key] => 2479370a3ed840cf184df1f5f00f32f1
 [sig] => 3d5b94ae50d6e65fbc94cc93326feffb
)

Example (PHP)

If you are using the Sailthru PHP client library, the function receiveOptoutPost() returns true if the incoming POST data matches that of an opt-out postback.

$sailthruClient = new Sailthru_Client($api_key, $api_secret);
  if ($sailthruClient->receiveOptoutPost()) {

      switch ($_POST['mode']) {
          case 'all':
              // respond to an opt-out all

          case 'basic':
              // respond to an opt-out basic

          case 'blast':
              // respond to an opt-out blast

          case 'template':
              // respond to a template optout ($_POST['template'] has the name)

          }
      } else {
      <a href="http://www.php.net/header" rel="nofollow">header</a>('HTTPS/1.1 403 Forbidden');
  }

You can be notified whenever an email hardbounces.

To turn on hardbounce postbacks, set the Hardbounce Postback URL in your API & Postbacks Settings page.

Sailthru will POST the following parameters:

• email  – the email address that hardbounced
• send_idor blast_id  – the identifier for the message that caused the hardbounce

The API key and a hashed signature will also be included in this post.

Example hardbounce postback data:

Post Data:
Array
(
    [email] => blashsdsd@dfsdf.com
    [send_id] => WFQKQW5K3LBgi0mk
    [action] => hardbounce
    [api_key] => 6b805755ce5a23e3c0459aaa598efc56
    [sig] => 13b3987b656c7771fcac92982fdfb331
)