What security considerations should be taken into account when implementing a printing feature in PHP?

When implementing a printing feature in PHP, it is important to consider security concerns such as preventing malicious code injection and protecting sensitive data. One way to address these issues is by sanitizing user input and using proper authentication and authorization mechanisms to control access to the printing functionality.

// Sanitize user input before printing
$user_input = filter_input(INPUT_POST, 'user_input', FILTER_SANITIZE_STRING);

// Check if user is authorized to print
if($user->isAuthorized('print')){
    // Print the sanitized user input
    echo $user_input;
} else {
    echo "You are not authorized to print.";
}