webhook.php

<?php
require 'vendor/autoload.php';
$AccessToken    = 'APP_USR-1159009372558727-072921-8d0b9980c7494985a5abd19fbe921a3d-617633181';
MercadoPago\SDK::setAccessToken($AccessToken);
$body = @file_get_contents('php://input');
$data = json_decode($body);
file_put_contents('notificaciones/' . $data->id . ".json", $body);
switch ($data->type) {
    case "payment":
        //$payment = MercadoPago\Payment::find_by_id($_POST["data"]["id"]);
        $payment = MercadoPago\Payment::find_by_id($data->data->id);
        http_response_code(201);
        // var_dump($payment);
        break;
    case "test":
        echo "ok";
        break;
    case "plan":
        $plan = MercadoPago\Plan::find_by_id($_POST["data"]["id"]);
        break;
    case "subscription":
        $plan = MercadoPago\Subscription::find_by_id($_POST["data"]["id"]);
        break;
    case "invoice":
        $plan = MercadoPago\Invoice::find_by_id($_POST["data"]["id"]);
        break;
}

?>