Nginx negating condition/ if else

Question

I've came into situation where I cannot find a way around it, neither with tons googling.

valid_referers none blocked something.com;
if ($invalid_referer) {
    rewrite ^ /leech.jpg;
    expires epoch;
}

Everything works fine so far, but I want to create if referer is valid to expire max; I couldn't find how to negate if statement or create else in nginx configuration. I tried:

else {
    expires max;
}

or (notice exclamation mark)

if(!$invalid_referer){
     expires max;
}

but it doesn't work as it works in almost everywhere.

Answer 1

Try to make one setting default and other one turned on by condition:

expires max;

valid_referers none blocked something.com;
if ($invalid_referer) {
    rewrite ^ /leech.jpg;
    expires epoch;
}