What are some common challenges when creating a forum portal using PHP?

One common challenge when creating a forum portal using PHP is implementing user authentication and authorization to ensure that only registered users can access certain features or post content. This can be solved by using sessions to store user login information and checking user roles before allowing them to perform certain actions.

// Start session
session_start();

// Check if user is logged in
if(!isset($_SESSION['user_id'])){
    header("Location: login.php");
    exit();
}

// Check user role before allowing access
if($_SESSION['user_role'] != 'admin'){
    echo "You do not have permission to access this page.";
    exit();
}