PHP sessions are not setting

Question

I am creating a simple login system and am encountering that everytime I try to login the session fails to set and returns my error to me.

The code is posted below.

• Form:

  <form action="login_system.php" method="post">
  Username<br>
  <input type="text" name="username"><br>
  Password<br>
  <input type="password" name="password"><br>
  <input type="submit" name="submit" value="login">
  </form>
  

• login_system.php:

  error_reporting(E_ALL ^ E_NOTICE);
  
  $user = $_POST['username'];
  $pass = $_POST['password'];
  
  if (isset($_POST['submit']) && $user == 'test' && $pass == 'test') {
      session_start();
      $_SESSION['logged_in'] == 'yes';
      if ($_SESSION['logged_in'] == true) {
          echo '<META HTTP-EQUIV="Refresh" Content="0; URL=main_index.php">'; 
      }
  }
  

• Page to login to:

  session_start();
  require('login_system.php');
  
  
  if ($_SESSION['logged_in'] == 'true') {
      echo 'ok';  
  } else {
      die ('You do not have permission to view this webpage.');   
  }
  

Answer 1

the session is being called on the login page. Try removing it and it should fix your issue.

Answer 2

session_start() must got at the top of each page you use sessions on. In your "Login_system" page it is not. It should look like this:

session_start();
error_reporting(E_ALL ^ E_NOTICE);

$user = $_POST['username'];
$pass = $_POST['password'];

if (isset($_POST['submit']) && $user == 'test' && $pass == 'test') {
    $_SESSION['logged_in'] = 'yes';
    if ($_SESSION['logged_in'] == true) {
        echo '<META HTTP-EQUIV="Refresh" Content="0; URL=main_index.php">'; 
    }
}

Also,

$_SESSION['logged_in'] == 'yes';

should only have one equal sign:

$_SESSION['logged_in'] = 'yes';

Two equal signs are a comparison operator. You want one which is the assignment operator.

Answer 3

You have the following which is a comparison operator. A assignment operator is just =

$_SESSION['logged_in'] == 'yes';
                       ^
if ($_SESSION['logged_in'] == true) {#you can probably remove this line

Which should be

$_SESSION['logged_in'] = 'yes';# or true?

Then you have 'true' which is actually 'yes' or unless you are looking for == true and not string true

if($_SESSION['logged_in'] == 'true') {

Which should be one of the following but make sure you are consistent

if($_SESSION['logged_in'] == 'yes') {

OR

if($_SESSION['logged_in'] == true) {