Trick PHP into thinking SSL/HTTPS is on
Not sure of the implications of this/best practices, but I just added
$_SERVER['HTTPS'] = 'on';
to my index.php.
Reason for this is that I am running a php app behind a reverse proxy, with the connection between the app server and the reverse proxy being plain HTTP, but the connection between the client and the reverse proxy is HTTPS.
Themocracy