如何在 php 中跟踪注销时间会话并将其作为数据库保存在 mysql 中

Question

I want to ask about logout times session in PHP.

The code if the user logs into the system:

<?php 

    // the login validation page 

    $the_username = $_POST['the_username'];
    $the_password = $_POST['the_password'];

    $login_date = date("Y-m-d");
    $login_time = date("H:i:s");

    $query = mysqli_query($conn,"SELECT * FROM tbl_user WHERE usr = '$the_username' AND pwd = '$the_password'");
    $result = mysqli_num_rows($query);


    if ($result > 1) {
        $fetch = mysqli_fetch_assoc($query);
        $_SESSION['the_username'] = $fetch['usr'];
        $_SESSION['the_password'] = $fetch['pwd'];
        mysqli_query($conn,"INSERT INTO track_log_user(`id`,`username`,`login_date`,`login_time`,`logout_date`,`logout_time`) VALUES (NULL,`$_SESSION[the_username]`,'$login_date','$login_time','','')");
        header("location:my_menu.php");
    }
    else {
        echo "Your Login Is Incorrect";
        header("location:index.php");
    }

  ?>

The code if user clicks logout button:

<?php
require_once ('connections.php');
// this is logout page when user click button logout in system page

session_start();
$time = date("H:i:s");
$date = date("Y-m-d");
mysqli_query($conn, "UPDATE track_log_user SET logout_date = '$date' AND logout_time = '$time' WHERE username = '$_SESSION[the_username]'");
$_SESSION = NULL;
$_SESSION = [];
session_unset();
session_destroy();
header("location:index.php");
?>

And my question is how if the client is idle or browser error or laptop crash or force close window/tab and their session is ended automatically and logout?

How my tracking user login and logout date-time backend system will working??

I want to make my task easier for making a monthly report for how many customers/clients are visiting and using our website.

Answer 1

if you want to track user session, then you need to store data into their browser example (cookie).

Syntax for PHP

setcookie(name, value, expire, path, domain, secure, httponly);

Only the name parameter is required. All other parameters are optional.

you can use md5 or any hashing technique to mask your data.

But, if you don't want to store data into their browser, you can create temporary database for the current user session. Whenever the user creates any event (eg clicking button, or request a webpage), you can search for the database if he is already out.

After removing data, you can delete the user's temporary data to save space.

Edit: Try using this instead

$datetime = date("Y-m-d H:i:s"); 
$timestamp = strtotime($datetime); //in milliseconds
mysqli_query($conn,"UPDATE users SET logout_timestamp = '$timestamp ' WHERE username = '$_SESSION[the_username]'");

To get the hour/min/sec, first load the stored timestamp of the user in the database, then also get the current timestamp.

//set maximum session (global variable), example 30 minutes
$_MAXIMUM_SESSION_IN_SEC = 60*30;


$timestamp_difference = $new_timestamp - $old_timestamp
if($timestamp_difference/1000 > $_MAXIMUM_SESSION_IN_SEC)
{
    //logout here
}
else 
{
    //remaining time for display
    $seconds= floor((timestamp_difference % (1000 * 60)) / 1000);
    $minutes= floor((timestamp_difference % (1000 * 60 * 60)) / (1000 * 60));
    $hour = floor((timestamp_difference % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
    //echo here
}

Since you are talking about client side. Add javascript. Try this.

<script>
// fetch data from sql
var oldTimestamp = <?php echo $timestamp_from_sql; ?> ;

// Update the every 1 second
var x = setInterval(function() {

  // Get current timestamp
  var currentTimestamp = Date.now();

  // Find timestamp difference
  var timestamp_difference = currentTimestamp - oldTimestamp;

  // Time calculations for hours, minutes and seconds
  var hours = Math.floor((timestamp_difference % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
  var minutes = Math.floor((timestamp_difference % (1000 * 60 * 60)) / (1000 * 60));
  var seconds = Math.floor((timestamp_difference % (1000 * 60)) / 1000);

  // Display the result in the element with id="demo"
  document.getElementById("demo").innerHTML = hours + "h "
  + minutes + "m " + seconds + "s ";

  // If above the session limit, logout the user
  if (distance > maximumSessionInSec) {
    clearInterval(x);
    document.getElementById("demo").innerHTML = "SESSION EXPIRED";
    //add other code here to reload the page
    //or add ajax code to update files in the server
  }
}, 1000);
</script>