MailChimp Add Subscriber using API 3.0 PHP - php

Question

I am trying to add a php file that adds a new subscriber to my MailChimp list. Here is my form that SHOULD trigger the php file to add the new subscriber:
<form action="/scripts/freemonth_action.php" class="email_form_freemonth" method="post">
<h3>Get your first month free</h3>
<div class="form-group customised-formgroup"> <span class="icon-user"></span>
<input type="text" name="full_name" class="form-control" placeholder="Name">
</div>
<div class="form-group customised-formgroup"> <span class="icon-envelope"></span>
<input type="email" name="email" class="form-control" placeholder="Email">
</div>
<!--<div class="form-group customised-formgroup"> <span class="icon-telephone"></span>
<input type="text" name="phone" class="form-control" placeholder="Phone (optional)">
</div>-->
<div class="form-group customised-formgroup"> <span class="icon-laptop"></span>
<input type="text" name="website" class="form-control" placeholder="Website (optional)">
</div>
<!--<div class="form-group customised-formgroup"> <span class="icon-bubble"></span>
<textarea name="message" class="form-control" placeholder="Message"></textarea>
</div>-->
<div>
<br>
<button style="margin: 0 auto" type="submit" class="btn btn-fill full-width">GET FREE MONTH<span class="icon-chevron-right"></span></button>
</div>
</form>
And here is freemonth_action.php:
<?php
session_start();
if(isset($_POST['submit'])){
$name = trim($_POST['full_name']);
$email = trim($_POST['email']);
if(!empty($email) && !filter_var($email, FILTER_VALIDATE_EMAIL) === false){
// MailChimp API credentials
$apiKey = '6b610769fd3353643c7427db98d43ad6-us16';
$listID = '0cf013d1d9';
// MailChimp API URL
$memberID = md5(strtolower($email));
$dataCenter = substr($apiKey,strpos($apiKey,'-')+1);
$url = 'https://' . $dataCenter . '.api.mailchimp.com/3.0/lists/' . $listID . '/members/' . $memberID;
// member information
$json = json_encode([
'email_address' => $email,
'status' => 'subscribed',
'merge_fields' => [
'NAME' => $name,
]
]);
// send a HTTP POST request with curl
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_USERPWD, 'user:' . $apiKey);
curl_setopt($ch, CURLOPT_HTTPHEADER, ['Content-Type: application/json']);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 10);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'PUT');
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_POSTFIELDS, $json);
$result = curl_exec($ch);
$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);
echo json_encode($result);
// store the status message based on response code
if ($httpCode == 200) {
$_SESSION['msg'] = '<p style="color: #34A853">You have successfully subscribed to CodexWorld.</p>';
} else {
switch ($httpCode) {
case 214:
$msg = 'You are already subscribed.';
break;
default:
$msg = 'Some problem occurred, please try again.';
break;
}
$_SESSION['msg'] = '<p style="color: #EA4335">'.$msg.'</p>';
}
}else{
$_SESSION['msg'] = '<p style="color: #EA4335">Please enter valid email address.</p>';
}
}
I'm not even sure how to debug this, because when i do echo $result (or anything like that) I do not see anything on the page or logged to the console. I'm also open to any suggestions that use javascript as long as it is still the 3.0 API.

Answer 1

Your subscription code works fine. The reason you aren't seeing any result is because isset($_POST['submit']) looks for an element with the name 'submit' rather than the type 'submit'. Just add the name attribute to your button, and it should work for you:
<button style="margin: 0 auto" type="submit" name="submit" class="btn btn-fill full-width">GET FREE MONTH<span class="icon-chevron-right"></span></button>
Also, you should keep the API key secret so other people can't access your MailChimp account through the API. I'd recommend disabling your current key and creating a new one. See MailChimp's knowledgebase article about API Keys for more details.