add.php

<?php
//include "customfunctionlibrary.php";
if (!isset($_POST['g-recaptcha-response'])){
    header("Location: https://multiurl.sftg.io/?error=noCaptcha");
    die();
}
$captcharesponse = $_POST['g-recaptcha-response'];

$url = 'https://www.google.com/recaptcha/api/siteverify';
$data = array('secret' => getenv('RECAPTCHA_SECRET_MULTIURL'), 'response' => $captcharesponse);

// use key 'http' even if you send the request to https://...
    $options = array(
        'http' => array(
            'header'  => "Content-type: application/x-www-form-urlencoded\r\n",
            'method'  => 'POST',
            'content' => http_build_query($data)
            )
        );
        $context  = stream_context_create($options);
        $result = file_get_contents($url, false, $context);
        if ($result === FALSE) { 
            header("Location: https://multiurl.sftg.io/?error=captchaError");
            die();
        }
        
        $captcharesult = json_decode($result,1);
        
        if ($captcharesult["success"]){
            
            $dbserver = getenv('MYSQL_SERVER_MULTIURL');
            $dbusername = getenv('MYSQL_USER_MULTIURL');
            $dbpassword = getenv('MYSQL_PASSWORD_MULTIURL');
            $dbname = getenv('MYSQL_DB_MULTIURL');
            $dbport = getenv('MYSQL_PORT_MULTIURL');
            $dbaccess = true;
            
            // Create connection
            $mudbconn = new mysqli($dbserver, $dbusername, $dbpassword, $dbname, $dbport);
            
            // Check connection
            if ($mudbconn->connect_error) {
                header("HTTP/1.1 500 Internal Server Error");
                die("Database connection error");
            }
            
            $urlsarr = $_POST['url'];
            $urlsarr_sanatized = [];
            
            //Sanatise URLs
            foreach ($urlsarr as $cururl){
                $sanurl = filter_var($cururl, FILTER_SANITIZE_URL);
                if (!filter_var($sanurl, FILTER_VALIDATE_URL) === false) {
                    //All good
                    array_push($urlsarr_sanatized,$sanurl);
                } else {        
                    header("Location: https://multiurl.sftg.io/?error=invalidURL");
                    die();
                }            
            }
            
            $urlnamearr = $_POST['name'];
            $urlnamearr_sanatized = [];
            
            foreach ($urlnamearr as $curname){
                array_push($urlnamearr_sanatized,filter_var($curname, FILTER_SANITIZE_STRING));
            }
            
            //Combine into JSON
            $urlsjson = json_encode(array_combine($urlsarr_sanatized,$urlnamearr_sanatized));
            
            $title = filter_var($_POST['pagetitle'], FILTER_SANITIZE_STRING);
            
            function generateshortlink(){
                //global $dbserver,$dbusername,$dbpassword,$dbname,$dbport;
                global $mudbconn;
                //Generate random shortlink
                $newshortlink = substr(md5(microtime()),rand(0,26),7);
                //Check to see whether record with short name already exists
                
                // prepare and bind
                $stmt = $mudbconn->prepare("SELECT id FROM multiurl WHERE shortlink = ?");
                $escapedshortlink = mysqli_real_escape_string($mudbconn,$newshortlink);
                $stmt->bind_param("s", $escapedshortlink);
                
                $getinfoResult = $stmt->execute();
                $mysqlResult = $stmt->get_result();
                $stmt->close();
                
                if ($mysqlResult->num_rows != 0){
                    return false;
                }
                else{
                    return $newshortlink;
                }
                
            }
            
            $newshortlink = generateshortlink();
            //Cycle through shorlinks until one that hasn't been found yet
            while ($newshortlink == false) {
                $newshortlink = generateshortlink();
            }
            
            //$uploadresult = upload_to_db('multiurl','shortlink,count,urls,title',"'".$newshortlink."',0,'".$urlsjson."','".$title."'");
            $table = 'multiurl';
            $item = 'shortlink,count,urls,title';
            $values = "'".$newshortlink."',0,'".$urlsjson."','".$title."'";

            $uploaddataSQL = "INSERT INTO ".mysqli_real_escape_string($mudbconn,$table)." (".$item.") VALUES (".$values.")";
            
            // Fetch all
            if (mysqli_query($mudbconn, $uploaddataSQL)) {
                $uploadresult = "New record created successfully";
            } else {
                $uploadresult = "Error: " . $uploaddataSQL . "---" . mysqli_error($mudbconn);
            }
            
            //Close DB Connection
            $mudbconn->close();
            
            if ($uploadresult == "New record created successfully"){
                header("Location: https://multiurl.sftg.io/".$newshortlink);
                die();
            }
            else{
                header("Location: https://multiurl.sftg.io/?error=".$uploadresult);
                die();
            }
        }
        //Captcha failed
        else{
            header("Location: https://multiurl.sftg.io/?error=".urlencode($result));
            die();
        }
        
        ?>