pdo connection not working in php function

Question

I have this function which is for throttling login, but I have problem, the pdo connections do not work inside the function, it gives me error for "undefined $conn or call to a member query function on null", if I'm correct it is due to the scope, is there any work around this?

<?php
function check(){
    function get_multiple_rows($getfailed) {
        $rows = array();
        while($row = $getfailed->fetch(PDO::FETCH_ASSOC)) {
            $rows[] = $row;
        }
        return $rows;
    }
    $throttle = array(1 => 1, 5 => 2, 30 => 10);
    if ($getfailed = $conn->query("SELECT MAX(attempted) AS attempted FROM failed_logins")){
        $rows = get_multiple_rows($getfailed);
        $getfailed->closeCursor();
        $latest_attempt = (int) date('U', strtotime($rows[0]['attempted']));
        if ($getfailed = $conn->query("SELECT COUNT(1) AS failed FROM failed_logins WHERE attempted > DATE_SUB(NOW(), INTERVAL 15 minute)")){
            $rows = get_multiple_rows($getfailed);
            $getfailed->closeCursor();
            $failed_attempts = (int) $rows[0]['failed'];
            krsort($throttle);
            foreach ($throttle as $attempts => $delay){
                if ($failed_attempts > $attempts) {
                    $remaining_delay = (time() - $latest_attempt) - $delay;
                    if ($remaining_delay < 0){
                        echo "You have exceeded the login attempts limit";
                    }
                    return false;
                    break;
                }else{
                    return true;
                }
            }
        }
    }
}
?>

Where is your $conn initialize? Other file ? Is a class that you can set as attribute? — Sergi Case, Apr 29 '16 at 10:31
If you turn on [PDO exceptions](http://php.net/manual/en/pdo.error-handling.php) then errors are a lot more obvious. — tadman, Apr 29 '16 at 10:32

score 0 · Answer 1 · edited May 23 '17 at 11:59

0

Obviously you have not defined $conn in your function. You have to define $conn in your function locally in order to be able to send request over it or consider reading this answer to properly setup PDO Connection globally in your web application.

edited May 23 '17 at 11:59

Community

1
1

answered Apr 29 '16 at 10:32

Zohaib Aslam

156
1
11

Or you could pass `$conn` as an argument to the function. – Rick Apr 29 '16 at 10:34

score 0 · Accepted Answer · answered Apr 29 '16 at 10:44

You could try to make your check Function receive an Argument like so:

<?php 
    function check(PDO $conn){
        function get_multiple_rows(PDOStatement $getfailed) {
            $rows = array();
            while($row = $getfailed->fetch(PDO::FETCH_ASSOC)) {
                $rows[] = $row;
            }
            return $rows;
        }
        $throttle = array(1 => 1, 5 => 2, 30 => 10);
        if ($getfailed = $conn->query("SELECT MAX(attempted) AS attempted FROM failed_logins")){
            $rows = get_multiple_rows($getfailed);
            $getfailed->closeCursor();
            $latest_attempt = (int) date('U', strtotime($rows[0]['attempted']));
            if ($getfailed = $conn->query("SELECT COUNT(1) AS failed FROM failed_logins WHERE attempted > DATE_SUB(NOW(), INTERVAL 15 minute)")){
                $rows = get_multiple_rows($getfailed);
                $getfailed->closeCursor();
                $failed_attempts = (int) $rows[0]['failed'];
                krsort($throttle);
                foreach ($throttle as $attempts => $delay){
                    if ($failed_attempts > $attempts) {
                        $remaining_delay = (time() - $latest_attempt) - $delay;
                        if ($remaining_delay < 0){
                            echo "You have exceeded the login attempts limit";
                        }
                        return false;
                        break;
                    }else{
                        return true;
                    }
                }
            }
        }
    }

Now you can pass the $conn to your Function like so:

<?php
    check($conn);

Hope this helps...

pdo connection not working in php function

2 Answers2