lib.php

<?php
function request($requestUrl, $accessToken, $action, $fields = [], $post = true) {

    $requestUrl = $requestUrl . '/' .  $action . '.json?access_token=' . $accessToken;

    $fields = http_build_query($fields);

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $requestUrl);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_TIMEOUT, 180);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    if ($post) {
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $fields);
        $requestHeaders = array(
            'Content-Type: application/x-www-form-urlencoded; ',
            'Content-Length: ' . strlen($fields),
        );
        curl_setopt($ch, CURLOPT_HTTPHEADER, $requestHeaders);
    }

    $response = curl_exec($ch);

    $result = json_decode($response, true);

    if ($result ===  null) {
        echo "\nGot NULL Response. Actual response: \n";
        var_dump($response);
        echo curl_error($ch);
    }
    curl_close($ch);

    return $result;
}