Making the variable unset after two minutes - php

Question

Hey guys am writing a small validation script which uses a simple token to login from the input..When the token is right the user must succesfully login and after two minutes the token must expire and give user a message token expired..But here when i use the token it also came with the message token destroyed ..i want to use the token for 2 minutes and i want the token to be expired in 2 minutes.
I have the html file
<form action="gethints.php" method="post">
First name: <input type="text" name="fname"><br>
<input type="submit" value="Submit">
</form>
Php file
<?php
$name = $_POST['fname'];
$currenttime = time();
$token = 'sample';
$timetounset = strtotime("2 minutes");
if($name != $token) {
echo 'you cant login';
} else {
echo 'you have succesfully logged in <br>';
}
if($currenttime > time() - $timetounset) {
unset($token);
echo "you cant use this token anymore";
} else {
echo 'token is not destroyed';
}
When i run this code and type sample in the input box i get the message like
you have succesfully logged in
you cant use this token anymore
What i need is when i type the id as sample i want to get the message you have succesfully logged in and after two minute when i use the same id i need to get the message like you cant use this token anymore
Thanks for your help..

Answer 1

Could use a session here:
first, store the last time the user made a request
<?php
$_SESSION['timeout'] = time();
?>
in subsequent request, check how long ago they made their previous request
<?php
if ($_SESSION['timeout'] + 2 * 60 < time()) {
// session timed out
} else {
// session ok
}
?>
EDIT:
Don't forget to have session_start(); on top of your code && check if $_SESSION['timeout'] exists, above code is just an example.

Answer 2

The most simple way to approach this imo is to set a cookie with an expiration of 2 minutes.
Store a variable or flag in the cookie and check the contents each time you want to do a validation.
setcookie("TestCookie", $value, time()+120);
Read out the value:
if (isset($_COOKIE['TestCookie'])) {
// Good cookie
} else {
// expired or invalid
}
For information on how to set a cookie and expiration:
http://php.net/manual/en/function.setcookie.php

Answer 3

People can play around with cookies. I suggest you create a database table tokens with token and expires columns. When you insert the token add this to your sql. ...... Insert ....... Timestampadd(now(), interval minute 2); To validate just check if now() is less than expires.