Can't POST to Shopify Private App using PHP+cURL - php

Question

Can't seem to find an error in my PHP code. I am trying to add a customer over Shopify API, below is my code. I tried the same URL using Postman and it worked - the user gets added when I add the same JSON string. So I know that API is enabled properly with correct permissions within Shopify.
$API_KEY = '****';
$PASS = '****';
$STORE_URL = '****';
$DATE = "2021-07";
$USER_EMAIL = 'test#test.com';
$baseUrl = 'https://'.$API_KEY.':'.$PASS.'#'.$STORE_URL.'/admin/api/'.$DATE.'/customers.json';
// post to: POST /admin/api/2021-07/customers.json
$data = array('customer' =>
array(
'first_name' => 'Promo',
'last_name' => 'User',
'email' => $USER_EMAIL,
'accepts_marketing' => 'true',
),
);
echo "test post data:";
echo json_encode($data);
$session = curl_init( $baseUrl );
curl_setopt($session, CURLOPT_HEADER, false);
curl_setopt($session, CURLOPT_RETURNTRANSFER, true);
curl_setopt($session, CURLOPT_HTTPHEADER, array('Content-Type: application/json'));
curl_setopt($session, CURLOPT_POSTFIELDS, json_encode($data));
curl_setopt($session, CURLOPT_CUSTOMREQUEST, 'PUT');
curl_setopt($session,CURLOPT_SSL_VERIFYPEER,false);
$response = curl_exec($session);
curl_close($session);
$json = json_decode( $response, true );
echo "test return data:";
var_dump($json);
The code prints the following, returning NULL and no customer is added:
test post data:{"customer":{"first_name":"Promo","last_name":"User","email":"test#test.com","accepts_marketing":"true"}}test return data:NULL
Can anyone spot what am I doing wrong here?

Answer 1

Never mind, I just figured it out.
The line
curl_setopt($session, CURLOPT_CUSTOMREQUEST, 'PUT');
Should be
curl_setopt($session, CURLOPT_CUSTOMREQUEST, 'POST');