Post PHP Session via Curl (Mailchimp API)

Question

I'm trying to update subscribers automatically to a Mailchimp list. I can update the list using a string from a form etc. However the e-commerce site I'm working on already has an email address stored in the session which I need to use but it's lost when using Curl. Can anyone help?

The example below is using a form which I've included for reference.

<?php
session_start();
if(isset($_POST['submit'])){
$email = $_POST['email'];
if(!empty($email) && !filter_var($email, FILTER_VALIDATE_EMAIL) === false){
    // MailChimp API credentials
    $apiKey = 'xxx-us14';
    $listID = 'xxxxxxxx';

    // 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',
        'double_optin'   => false,
        'send_welcome'  => true,
        'update_existing'   => false,
        'replace_interests' => false,
        'merge_fields'  => [
            'FNAME'     => $fname,
            'LNAME'     => $lname
        ]

    ]);

    // 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);

Answer 1

If you are wanting to pull data out of your session you will need to use the PHP $_SESSION superglobal. The code above looks to be using the $_POST superglobal and accessing its email value. $_SESSION Documented here: http://php.net/manual/en/reserved.variables.session.php

I do want to mention that its traditionally not a safe practice to send data read directly from your session in an over the wire request. If this is a form I would suggest making use of the $_POST you are already sending. If you don't want your user to have to input their email address you could use a pre-populated hidden field on your form.