How can a script be set to only be accessible via HTTPS and not HTTP in PHP?

To ensure that a script is only accessible via HTTPS and not HTTP in PHP, you can check the $_SERVER['HTTPS'] variable to determine if the request is using HTTPS. If the variable is not set or is not equal to "on", you can redirect the user to the HTTPS version of the script. 

if(empty($_SERVER['HTTPS']) || $_SERVER['HTTPS'] !== 'on') {
    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
    exit;
}

Keywords

PHP script HTTPS HTTP accessibility

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