Ryan | Add to Cart Apps commented on Creating webhook for Uninstalling an Shopify App in PHP

There are a few little things such as the SITE_URL being outside the brackets and the use of curl HTTPPOST. I tested the below request and it looks ok. Also ereg is depreciated so I switched that out.

function registerShopifyAppUninstallWebhook($shop_domain, $access_token){
    $API_KEY = SHOPIFY_API_KEY;
    $SECRET = SHOPIFY_SHARED_SECRET;
    $TOKEN = $access_token;
    $STORE_URL = $shop_domain;

    $url = 'https://'; . $STORE_URL . '/admin/webhooks.json';

    $params = '{"webhook": {"topic": "app/uninstalled","address": "'.SITE_URL.'users/setShopifyUninstall","format": "json"
}}';

    $session = curl_init();

    curl_setopt($session, CURLOPT_URL, $url);
    curl_setopt($session, CURLOPT_POST, 1);
// Tell curl that this is the body of the POST
    curl_setopt($session, CURLOPT_POSTFIELDS, $params);
    curl_setopt($session, CURLOPT_HEADER, false);
    curl_setopt($session, CURLOPT_HTTPHEADER, array('Accept: application/json', 'Content-Type: application/json', 'X-Shopify-Access-Token: '.$TOKEN));
    curl_setopt($session, CURLOPT_RETURNTRANSFER, true);

    if(preg_match("/^(https)/",$url)) curl_setopt($session,CURLOPT_SSL_VERIFYPEER,false);

    $response = curl_exec($session);
    curl_close($session);

    $body =json_decode($response);

    if($body)
        return $body;
    else
        return "0";
}

Also I just looked at what request libraries are available for cake as using curl is very messy and leads to issues. It looks like it has a built in HttpSocket

http://book.cakephp.org/2.0/en/core-utility-libraries/httpsocket.html